pdf - Conservation and Restoration of Cultural Heritage

Managers
of Decay
Conservation
and Restoration
Edition 2013
Managers
of Decay
2
3
Introduction 4
Here we are!
Jørgen Wadum 10
The management of aesthetics and decay
Norman Tennent 20
Conservation science … or science for conservation?
Summary's 30
Abstracts of both Master’s- and post-Master’s-theses
Team C&R 96
Professors, lecturers and management
Alumni 116
Overview alumni
Colophon 128
2
4
Introduction
5
Here we are!
4
6
Here we are!
sion. Moreover, it is necessary to cultivate
insight in, and reflection on, the scientific
practice and the choices that have to be
made when interfering in the materials.
The team of the Conservation and restoration department (C&R) teaches the students
and the ‘conservator-restorers in training’
(rio’s) to use an analytical approach which
will help them develop a critical and
inquisitive attitude. Curiosity­combined
with inventiveness are key principles.
The programme consists of three
consecutive phases [table 1]; the minor,
the master and the post-initial phase, each
has its own didactical principle. The minor
provides a condensed introduction to several aspects of the profession: conservation
and restoration theory as well as the neces-
In 2005, the University of Amsterdam, was
passed the baton from the Dutch Cultural
Heritage Agency (then ICN, now RCE)
and the SRAL (Foundation Conservation
Studios Limburg) to further develop and
maintain the educational programme for
conservator-restorers in The Netherlands.
Now that the fourth group has graduated
the University, we can leave the early hectic
years behind us and take a moment to
realize how much we have accomplished.
Together with our partners, the RCE, SRAL,
the RMA and many other museums and
institutes that deal with cultural heritage,
we are trying to establish our Dutch educational and research programme in the
conservation and restoration of cultural
heritage within the international field. In
the last mid-term review of the programme
in 2010, the final conclusion of the panel
was: “The programme is among the leading
conservation programmes in Europe”¹
which gives us enough reason to keep
firmly upon this road. By incorporating
the programme in an academic setting,
the intention was not only to give a boost
to the profession of conservator-restorer
on the road to emancipation and professionalization, but also to establish conservation and restoration as an independent
scientific discipline.
The orientation of the educational programme is towards a scientific ­approach
to the profession, and can be seen to be
comparable with the orientation of the
programme a student follows to become
a doctor or a dentist. With each of these
educational programmes it is crucial
to combine specialist knowledge and
manual dexterity with an interdisciplinary
approach to the broad issues of the profes¹ Midterm review report, May 2010 p. 5.
7
6
sary skills are presented to the students,
and the insights and attitudes necessary
for a conservator-restorer are cultivated.
During the master phase the students are
confronted with all aspects of the profession within its role as a scientific discipline.
The students discover and develop their
manual dexterity and become aware of
the central role of research at all stages of
the conservation process. The goal of the
master course is not to inform the students
about every possible variety on a problem
they could encounter in their professional
career, but to teach them a methodology
and a critical attitude which enables them
to approach problems in conservation and
restoration with a scientific attitude and
from a scientific viewpoint. The students’
[table 1] Structure of the UvA C&R programme
8
capabilities for an integral approach to
conservation problems with all their
complexities, increases during the master.
Understanding the ‘why’ and the ‘how’
of the choices they make, the actions they
undertake, and the relations between
the object, its context, and the scientific
­properties of the material, is crucial for
this approach. The frame of reference they
obtain enables the master students to perform the research for their master thesis
with minimal supervision.
The post-initial phase (PI) prepares the
conservator-restorer in training (rio) for a
professional life as an academically-trained
conservator-restorer. During the PI-phase
the focus lies on independent work and the
gaining of experience both in the treatment
of objects as the undertaking of research.
The first year of the PI offers the rio the
chance to either develop in the broadness
of the profession, or to specialize. During
the internships in the second year the
duality of the programme – thinking and
doing – is applied in the professional field
enabling the rio to develop a working
routine while he is confronted with
increasingly difficult assignments. These
aspects eventually culminate in the writing of a PI-thesis based on a complex and
complete treatment.
The fact that research is an intrinsic part
of academic schooling is something we
teach our students from day one of their
training. Obviously the research has to be
relevant for the profession and for cultural
heritage and society in the broadest sense.
This relevance is most prominently visible
in the choice of the research questions
which have a direct impact on the relevance
of the results of the research. However
relevant the research may be, if the find-
ings will never leave the desk-drawer or
the hard-disk of the computer, neither the
profession cultural heritage, or society
as a whole will benefit from its results.
Visibility is therefore crucial. If people
are convinced that we have a collective
responsibility for our cultural heritage,
then the visibility of research results is indispensable for our professional colleagues
and for the keepers of cultural heritage. In
order to achieve this, our alumni are the
best ambassadors.
This publication defines the added
value of our programme by bringing to
fruition applicable knowledge for the
conservation profession. Please enjoy!
Suzanne Maarschalkerweerd
Programme manager Conservation and
restoration of cultural heritage
University of Amsterdam ■
8
9
10
Jørgen Wadum
10
11
The management of
aesthetics and decay
13
The management of aesthetics
and decay
[Jørgen Wadum] From a UvA-C&R perspective conservation can be described as a discipline involving examination, documentation, preventive
care, and research directed toward the long-term safekeeping of cultural
heritage objects. In a collaborative effort with curators / technical art
historians¹ and conservation scientists, the conservator-restorers² study
the structure of individual objects, materials and methods of fabrication,
as well as techniques and materials used in past conservation treatments.
This interdisciplinary approach provides not only vital information on
the makers’ original intent, but also generates knowledge of the feasibility
of possible interventions and the way in which conservation treatments
affect the structure and appearance of our heritage.
Conservation-Restoration
A conservator is constantly facing new and unique complex challenges,
when confronted with condition assessments and eventually a treatment
of cultural objects which are open to numerous interpretations and possibilities for their care. Success in caring for and preserving our multifaceted cultural heritage requires an academically trained professional who
is able to perceive what the object to be cared for is, where it originates
from, the context in which it was made, and the materials which were
employed. Furthermore, this perception should be fused with a similarly
sound knowledge and understanding of the deterioration and decay
mechanisms of the materials and a variety of measures which could be
implemented to preserve the object. By contextualising these qualities
gleaned from each object or group of objects by means of close scrutiny
with the naked eye, through the stereomicroscope or by means of various
photographic techniques or advanced (preferably non-destructive) scientific analyses, and placing the results in the broader context of the material and technical development of the artist or craftsman, the conservation
documentation reaches a level where the information is sufficient to serve
all purposes of understanding and caring for the physical materials which
constitute each object.
Conservation also embraces preventive conservation, remedial conservation and restoration. Conservation consists of indirect and direct
¹ The term ‘Technical art history’ was possibly for the first time the focus of Beckmann, J., (1739-1811) in his book
Einleitung zur Technologie oder zur Kenntniß der Handwerke, Fabriken und Manufakturen … nebst Beiträgen zur
Kunstgeschichte, Göttingen 1777. See Koller, M., “Technische Kunstgeschichte” in Forschung, Lehre und Praxis’,
in Kunstgeschichte aktuell, Der Verband österreichischer Kunsthistorikerinnen und Kunsthistoriker, vol. XXII (2005)
web-publication: http://kunsthistoriker.at/artikel.php?itemid=323&menuid=5&rubrikid=1&pubid=38#top
² The document “The Conservator-Restorer: a Definition of the Profession”, adopted in 1984 by ICOM-CC and successively by ICOM, uses the term ‘conservator-restorer’ as a compromise, as the same professional is called ‘conservator’
in English-speaking countries and ‘restorer’ in those where Romanic and Germanic languages are spoken. In this text,
for the sake of simplicity, the word ‘conservator’ comprises both terms and will be used throughout.
14
actions aiming at retarding deterioration and preventing damage by
­creating conditions optimal for the preservation of cultural heritage,
as far as is compatible with its social use. Preventive conservation also
encompasses correct handling, transport, use, storage and display, all
aspects that require guidelines and procedures based on the physical
behaviour and condition of the objects in question.
Restoration is strongly related to both preventive and remedial
conservation and covers processes of performing changes to an object or
structure with the aim of facilitating its perception, appreciation and understanding so that it will closely approximate its state at a specific time
in its history, while respecting as far as possible its aesthetic, historical
and physical properties.
Objects as messengers from the past
Conservation is also about the necessity of keeping the many-layered
documentary evidence that every old or recent artistic object holds. In
the future, enquiries will continue to be posed in connection with new
attempts of interpreting the work, and much too often essential clues
have been made incomprehensible or even removed or destroyed during
treatment because their meaning and relevance went unrecognised.³
Examples of this are the many 16th and 17th century panel paintings that
were dramatically thinned from the reverse and cradled in the 19th and
20th century. Apart from the significant side-effect of causing the panels
to become even more vulnerable to environmental impact our predecessors
often also removed substantial information about the production and the
maker of these oak boards.⁴ My research into the panel makers and their
practice in producing panels and of the impact of guild regulations on
branding and marking these with their individual house marks is but one
example of how significant this information may be for understanding
the genesis of a panel painting.⁵
We must realize that we only have the objects in our temporary care and
will hand them over to new generations whose care-taking will be guided
by their changing values. Our clients, the museum visitors and scholars
alike, come increasingly from cultural backgrounds different from those
in which the objects were created. Visitors may not be able to interpret
objects that are more than a hundred years old, and the lack of historical
knowledge amongst younger generations therefore places the effort and
the role of the conservator in a crucial new context. We are approaching a
situation in which conservators do not only treat and care for the objects
but also serve as an important link between the objects and the public.
³ Wetering, E. van de, “Die Oberfläche der Dinge und der museale Stil”, in Maltechnik Restauro II (1982), pp. 98-102.
⁴ Wadum, J., “Historical Overview of Panel-Making Techniques in the Northern Countries”, in Dardes, K. & A. Rothe
(eds.) The Structural Conservation of Panel Paintings. Proceedings of a Symposium at the J. Paul Getty Museum, 24-28
April 1995. Los Angeles (1998), pp. 149-177.
⁵ Wadum, J., “The Antwerp Brand on Paintings on Panels”, in Hermens, E., (ed.) Looking Through Paintings. The Study
of Painting Techniques and Materials in Support of Art Historical Research. Leids Kunsthistorisch Jaarboek XI (1998),
pp. 179-198.
14
15
Integrity of the object
It is often true that when a conservator is considering carrying out treatment of a work of art, the first question that springs to mind is how to do
it. The greater part of conservation research still focuses on the challenges
of the physical condition of the object, the deterioration of materials and
possible interventions. This question is the key issue for the conservator,
arising out of the need to keep an object. Questions such as what we
should preserve; why we choose to preserve particular objects; and for
whom we treat the objects are challenging concepts with which a conservator may not often trouble himself.
While concentrating on the treatment of an object the conservators
ought to address also the context in which the object was created, how
it was passed on through history, and its current function as a bearer of
culturally significant messages. I believe we need to be aware that our
work is more than just a matter of preserving material and structure.
Conservation also encompasses the preservation of non-tangible
cultural qualities and a vast array of information. Exhibiting objects is
not just a matter of putting them on display. We should be guided by
an obligation and responsibility to consider what the object was, how
it may have changed – and may further change. The attempt to answer
these questions will naturally be influenced by the culture in which
the conservator, technical art historian and conservation scientist is
immersed and may be quite complex, given that cultural objects are
increasingly seen as elements within an international context rooted
in cultural diversity.⁶
The crossroad between treatment (how and with what) and the
visual aesthetic impact (why and for whom) is the spot where we find
the conservator as manager of aesthetics and decay. Apart from dwelling
on how to conserve or restore an object he must consistently include a
consideration of the impact of a treatment on the recipients of the object,
the viewers. An alteration of a painting’s well-known or long-appreciated
message may reshape our understanding of the past. A growing degree
of professionalism, coupled with our collaboration with art historians
and highly specialised conservation scientists, is forcing us to realize that
our impact on objects, and the various consequences, are indeed our
responsibility.
Bridging the gap between object and the public
It is also here that we find a new and unique and crucial role of the conservator as bridging the gap between people and objects. Conservators
at large will have a much more visible function than ever before in both
today’s and tomorrow’s museums and cultural sectors, while being part
of a global society which is focusing on the sustainability of our multicultural heritage and its materiality.
⁶ Wadum, J., “Ravished images restored”, in Leonard, M., (ed.), Personal Viewpoints – Thoughts
about Paintings Conservation. Los Angeles 2001, pp. 59-72.
16
17
Conservation therefore appears to be much more than examination,
­analysis, treatment and physical care of objects but rather a profession that
is becoming an increasingly active player in museum policy programming
and facilities development. This leads to a function that could well be
regarded as collections care, regardless of professional delimitation. Thus
the act of conservation, in whatever context of collections care it takes
place, appears as a matter of shared responsibility amongst many disciplines such as conservation and conservation science, curatorial work,
registration, collections management, education, building and maintenance, security, in-house and external exhibition, etc. All these potential
roles for the conservator within the heritage institutions each offers a
potential for contributions to information and documentation about
the objects in custody. Public conservation projects have been launched
in several countries and prompted increasing community interest in the
complexity of understanding and keeping our past for the future.
Acknowledging that documentation and conservation both are words
that have been given a multitude of definitions and that offer extensive
overlapping with related disciplines, from information science and
management to education and research in (art) history and the natural
sciences, it is important to understand that all stakeholders within the
cultural sector, institutional or private, must expand their current definition of and need for conservation documentation. This definition covers
photographic documentation (analogue, on x-ray films, digital etc.),
drawings, schematic recordings, scientific samples and analytical charts,
written texts with a narrative summary and much more.
a­ ppreciate the mass of information gleaned from pooling the resources
of this variety of disciplines.
Collaborative interdisciplinary projects with participants from
both the humanities and the natural sciences (art historians, historians,
­conservators and conservation scientists) can repair the misconception
that these disciplines counteract each other, and actually function as a
torch of light for others.
Conservation documentation
Research
Throughout the last century the advance of the scientific examination
of works of art has completely transformed the way in which we evaluate objects. Employing an increasingly wide range of analytical tools,
researchers from the fields of art history, conservation and conservation
science have in many instances demonstrated the significance of working
together in an interdisciplinary manner. Originally simply called ‘technical studies’ (a reference to the early Fogg Art Museum publications from
the 1930s), these collaborative efforts now compose a rapidly increasing
field of study described as Technical Art History.⁷
With the academically trained Master’s in conservation, museums and
private customers are offered a most spectacular academic orchestration,
conservators being able to assess the objects in a scholarly manner as well
as mastering the complicated craft of treating them. The most challenging
(art) historical and scientific developments in the understanding of our
cultural heritage are taking place at interdisciplinary interfaces combining
the research of curators, conservators and conservation scientists. In
a growing number of museums this staff partnership has taught us to
Above we have stressed that the conservation and preservation of cultural
heritage is an interdisciplinary field requiring close cooperation between
conservators, archaeologists, (art) historians, collection managers and
museum curators on the one hand, and conservation scientists on the
other. It is broadly recognized that the scientific analysis of materials
contributes essential, and often indispensable, information to the comprehension, preservation and restoration of objects of cultural heritage.
The analysis of inorganic materials such as pigments, minerals, stone,
glass and metals, can be carried out reliably by a range of methods. So
while the natural sciences, as well as engineering, play a critical role in
the proper selection of conservation materials, methods and strategies,
scientific research in conservation is often conducted by scientists who
originally come from outside the cultural heritage field. These scientists
thus lack the affinity with the cultural heritage and conservation fields
necessary to fully understand and communicate the significance, but
also the consequences of their work, to non-technical colleagues. It can
thus convincingly be argued that parallel to the UvA education in Conservation & Restoration (C&R), complementary education in Conservation
Science (CS) and Technical Art History (tah) will complete the notion of
⁷ Ainsworth, M.W., “From Connoisseurship to Technical Art History: The Evolution of the
Interdisciplinary Study of Art”, in GCI Newsletter XX, no. 1 (Spring 2005), pp. 4-10.
16
[plate 1] Detail of a wooden
board with a logger-mark
from the Baltic area ca. 1500
18
19
[plate 2] Cross section of a paint
layer which, among others shows
lead white, carbon black, ocre,
zinnober and fillers
[plate 3] Teacher and students
discuss ceramic objects
institutions, museums and universities and the industries, often offers
­opportunities for new results and innovation. Fundraising in collaboration
and for interdisciplinary projects has a much better chance of success.
Conclusion
‘Scientific conservation’ is based on the assumptions that 1) the principal
aim of conservation is to preserve the integrity of the object, and that
2) this integrity is located in the object’s physical features and constituents. Therefore conservation should involve scientific research into the
work’s ‘true identity’ through the investigation of the material properties
of the original object. These are the properties that should be preserved
for the future or that one should strive at reclaiming by means of restoration. Preservation and restoration practice should, furthermore, minimize ­intervention and aim at avoiding, as much as possible, measures that
­cannot be reversed.
In many museums research-curators conduct their studies on a high
level of sophistication. The same could be said about research-conservators; a job description until now not often encountered in the museum
world. Conservation scientists, found only in a few museums, will be
expected to carry out research in order to understand the how of objects
and in order to come up with solutions to their safekeeping. The balance
between a continued focus on developing and exercising hands-on treatments with educating an academically trained conservator in tandem
with training technical art historians and conservation scientists should
be seen as a novel and important trinity aiming to create a strong inter­
disciplinary team caring for Collectie Nederland – and beyond.
It is in this complex interaction between a multitude of stakeholders,
the technical art historian-conservation scientist-conservator being a
unique trinity, that the UvA-C&R educates and researches for the benefit
of understanding and keeping objects of our diverse yet common
cultural of objects as mirrors of human expression for current and
future generations. ■
a trinity that, in collaboration, can research, understand and care for our
historical past, its aesthetics and decay.
We have an urge to make our conservation research relevant to others
both within and outside the heritage world. With open-access databases
to assist in spreading the meta-data of research achievements comparable
to that of the INCCA network and the rising importance of the RKD
databases on technical documentation. Contemporary artists are highly
experimental in their use of materials – often to such a degree that the deployment of fragile, ephemeral, degradable, and period-specific materials
has become a prominent characteristic of the art of today. As a result,
several art objects of the latest decades no longer exist in their original
form: they have either degraded severely, are in the process of change and
decay, or have been entirely or partly remade in more recent forms of
their original materials.
Collaborative projects between universities and (regional) museums
could facilitate better research infrastructures instigating shared databases
or research documentation programs.⁸ Such constructions may assist
museums and collections in answering questions like how we keep funding the conservation documentation, i.e. C&R, CS and TAH collaboration,
in its broadest sense when museums are constantly being put under
econo­mical pressure from governments. Collaboration between different
⁸ See the open source Mellon funded ConservationSpace project: www.conservationspace.org
18
20
Norman Tennent
20
21
Conservation science … or
science for conservation?
22
23
Conservation science … or science
for conservation?
[Norman H. Tennent] The previous article sets out our University of
22
Amsterdam Conservation and Restoration (UvA C&R) credo for conservation and in so doing acknowledges to the increasing sophistication of
the field in terms of the technological developments and the increasing
multi-disciplinarity which the academic education of conservator-restorers must embrace. One aspect of this is the need for an ever-stronger
scientific foundation on which conservation practice must be based. In
this essay, I wish to chart some key aspects of the discipline of conservation science with which conservator-restorers must become conversant.
­Conservation science is a very young academic field of study whose
potential contribution to conservation has never been greater, but to fulfil
its potential the scope of conservation science must be driven by the needs
of conservation. I wish, therefore, also to allude to the dangers of conservation science losing sight of the importance of contributing directly to
conservation practice. An analogy of the dangers faced by conservation
science was formulated by Gael de Guichen, a scientist whose awareness
of the needs of conservation is second to none. He pointed out, amusingly
and not entirely inaccurately, that there is the tendency for conservation
scientists to resemble satellites launched into space with a specific purpose but which stray from their path while continuing to send ever more
unintelligible messages back to earth.¹ That danger will be one of the
themes being discussed in Rome this year at an international forum on
conservation science, to which I shall return below.
Conservation science within the UvA C&R programme is, in actuality,
better referred to as ‘science for conservation’. Indeed this description
parallels the running title of a groundbreaking series of textbooks, Science
for Conservators, first produced in the 1980s and still used at UvA and
elsewhere as science teaching primers. The fundaments of science gained
in the three phases of our programme are designed to give graduates sufficient scientific grounding to undertake sophisticated diagnosis of conservation problems, carry out treatments and, if necessary, initiate further
scientific investigation. The goal is to provide the necessary scientific
‘toolkit’ which will underpin not only the expert execution of treatments
but also the provision of well-grounded advice on technical examination,
storage, display, handling, and maintenance of cultural heritage.
To achieve this goal our programme recognises that science has a central role in understanding the materials which constitute art and antiquities and is the basis for a proper appreciation of technical aspects of their
creation. Indeed, scientists have undertaken analyses of cultural heritage
since the beginning of experimental scientific endeavour as we now know
it, in the 18th century. However, the role of science in contributing to
24
heritage conservation and restoration is much more recent. The first museum laboratory founded at the end of the 19th century but it was not till
the 1960s that the discipline of conservation science emerged as a distinct
field of applied science and it was even later, in the 1970s, that the term
conservation scientist began to be used in conjunction with the preservation of cultural heritage. Since then, the subject has been evolving rapidly
and there have been regular attempts to define its scope in published
texts.¹ ² ³ A landmark international gathering of conservation scientists,
held in Bologna in 1999, specified⁴ the principal roles of conservation
science as: study, investigation and monitoring of cultural heritage and its
environment with respect to conservation and preservation; definition,­
development and evaluation of conservation concepts, materials, measures,
methods and techniques and the development of standards and guidelines;
provision of diagnosis before, during and after conservation interventions;
research on the causes and mechanisms of deterioration and the interpretation of scientific results for the benefit of conservation of cultural
heritage; communication of the scientific principles of conservation and
the promotion of scientific research in conservation; cooperation with
other disciplines.
At UvA, our teaching and research recognises the importance of a
strong scientific basis for optimal conservation in the 21st century while
nonetheless accepting that the scientific knowledge for a comprehensive
under-pinning of conservation practice is vast. Ultimately, this is best
developed­in the workplace by partnerships between conservator-restorers and scientists tackling conservation projects in a symbiotic relationship. We are fortunate that this close cooperation with conservation
scientists commences at the outset and continues throughout our 5-year
programme. In the ‘Ateliergebouw’, the superb conservation centre
which we share with scientists from the Dutch Cultural Heritage Agency
(RCE) and colleagues from the Rijksmuseum (RMA), the sharing of expertise with conservation­scientists and conservation practitioners infuses
both teaching and research. Examples of projects given in this essay will
demonstrate how the Ateliergebouw allows easy integration of scientific
analysis and experimentation as support for student conservation treatments or research projects (in both the Master’s and Post-Initial phases)
and for staff research. This involves primarily access to state-of-the art
instrumental analysis but no less relevant is the need for accelerated aging
facilities to predict the long-term behaviour of conservation materials.­It
¹ Guichen, G. de, “Scientists and the preservation of cultural heritage”, in Science, Technology and European Cultural
Heritage, Ed. Baer, N.S. et al., Butterworth-Heinemann, Oxford, 1991, pp. 17-26.
² Feller, R. L., “Concerning the Place of Science in the Scheme of Things”, in Contributions to Conservation Science.
A Collection of Robert Feller’s Published Studies on Artists’ Paints, Paper, and Varnishes, Ed. Whitmore, P. M., Carnegie
Mellon University Press, Pittsburgh, 2002, pp. 619-630.
³ Groen, K., “Perspectives on the evolution of science for art history and conservation, and its current state”,
in Paintings in the Laboratory: Scientific Examination for Art History and Conservation, unpublished PhD thesis,
University of Amsterdam, 2011, pp. 1-19.
⁴ ICCROM, University Postgraduate Curricula for Conservation Scientists, Proceedings of the International Seminar,
Bologna, Italy, 26-27 November 1999, ICCROM.
24
25
is no coincidence that the UvA classroom lessons on analytical techniques
are greatly enhanced by the access to the instrumentation itself, combined
with the experience of the analytical scientists, which the Ateliergebouw,
through the close working relationship with the RCE and RMA, provides.
The development of the discipline of conservation science needs to be
written; indeed, the history of conservation science in The Netherlands
alone remains, as yet, by no means fully documented. Karin Groen has
demonstrated³ how revelatory the details of that task would turn out to be.
Since the establishment of the Centraal Laboratorium voor Onderzoek
van Voorwerpen van Kunst en Wetenschap (Central Research­Laboratory
for Objects of Art and Science) 50 years ago, on 1st March 1963, The
Netherlands has played a leading international role in the development
and practice of conservation science. In her survey of national and inter­
national progress in conservation science, Karin Groen makes many
­telling points which deserve to be more widely known and discussed.
One key issue is; “does the research have consequences for the restoration?” She cites the example of the degradation of the yellow pigment,
cadmium sulfide. Despite much new information on the ensuing colour
changes (gained using the most sophisticated analytical facilities, including
[plate 1] Detail of Zeegezicht, an oil painting from 1909 by Piet Mondrian, in which the unstable
cadmium yellow paint is showing cracks and is lifting. Several paintings by Mondrian exhibit a
similar appearance; the yellow paint has a strong craquelure and some discoloration
26
27
[plate 3] Section of a test wall
constructed in 1967, in Limelette, Belgium,
to evaluate silicone waterproofing treatments
on 40 calcareous stones
[plate 2] Detail of a restored head from the
tympanum of the Royal Palace in the Dam Square,
Amsterdam. Most of the head was re-modelled,
in 1915, using a zinc-based paste to replace the
severely degraded marble original
synchrotron radiation) she observes that “what circumstances would
have triggered the process, and when, is still a mystery”. Relating scientific
analytical findings to treatment recommendations is often the most difficult part of the investigative process and here the collaborative role of the
conservator-restorer in the research is of great importance. Accordingly,
it is fitting that one current UvA C&R Master’s research project is addressing
practical aspects and consequences of this very phenomenon, associated
with paintings by Mondrian [plate 1]. This is but one example from our
C&R education of the vital role that conservator-restorers can play in
research, in collaboration with conservation scientists and we endeavour
to foster such collaboration progressively throughout our programme.
In this case, in addition to conservation colleagues from, amongst others,
the Municipal Museum in The Hague and the Kröller-Müller Museum,
the project is relying on collaboration and consultation with scientists
from the RCE, from the Science Faculty of UvA and from the Technical
University, Delft. In this way, we seek to inculcate an understanding of
the nature and scope of the role of conservation science in order to facilitate the ‘dialogue of equals’, between conservator-restorer and scientist,
which is necessary for implementing proper scientific investigations for
the benefit of conservation.
One other example will suffice here (in conjunction with many others
referred to elsewhere in this book) to reinforce the point. A team of C&R
staff, current and past students, and RCE researchers are involved with the
study of a fascinating material used for the repair the marble tympanum
of the Royal Palace in the Dam Square, Amsterdam. In 1915, because
of pollution-induced degradation of the marble, this material, a cement
based on zinc compounds, was extensively used for filling small lacunae
and for remodelling major components, such as complete heads [plate 2]
and other parts of the tympanum figures and ancillary items. As a result,
26
a large proportion of the marble tympanum now actually consists of this
material. Interestingly, its durability, after a century, has been shown to
be remarkably good. Consequently, the research takes the 1915 tympanum
repairs as the starting point to explore the scope for rehabilitation of this
material, currently not used in The Netherlands, in the expectation that a
versatile material, first prepared in the19th century⁵ and formerly used for
filling dental cavities (a rather different form of conservation), may have
great potential for the future conservation treatments.
This case study is an example of one of the aspects of conservation
­science – the prediction of long-term durability – which requires input from
conservator-restorers. The natural aging of the old tympanum repairs is a
century-long experiment and its documentation by conservator-restorers
contributes to our understanding of durability. Conservation requires,
however, predictions of the durability of new materials and the science
of natural and accelerated aging is one of the key facets of conservation
research on which our programme focuses. Here the RCE accelerated
aging apparatus, especially for light fading, is a crucial part of our C&R
experimental requirements, available nowhere else within UvA. The need
for acceleration of long-term behaviour requires a t­ horough understanding
of the relevant parameters and a rigorous implementation of them. The
state-of-the-art Ateliergebouw facilities therefore provide an exceptional
opportunity for student and staff research on long term behaviour of
­artists’ and conservation materials. Nonetheless, accelerated aging is no
substitute for the results of natural aging. For this, considerable planning
and patience is required but its value is clearly demonstrated by the
­illustration [plate 3]. In 1967, panels of 40 different calcareous stones
⁵ Sorel, S., “Procédé pour la Formation d’un Ciment Très-Solide par l’Action d’un Chlorure sur l’Oxyde de Zinc.”
Compte Rendu Hebdomadaire des Séances de l’Academie des Sciences, 41 (1855), p. 784.
28
25% Materials & techniques
24% Investigation tools & methods
12% Treatment
11% Preventive
9% Management
9%History policy other legislation
terminology
5% Education & training
4% Deterioration
1% Other
[plate 4] Pie chart based on 357 articles from
10 conservation periodicals / conference proceedings in
2008 illustrating the relative focus on different conservation
science topics. Illustration: ICCROM, 2013
(24 of which are shown in this illustration), all used for building facades,
were installed outdoors in a test wall in a rural site in Belgium. The
­lateral sections were treated with silicone resins and the central section
left untreated. After more than thirty years, the relative effectiveness
of the stone treatments and the different response of the various stone
types to the waterproofing is clearly visible, an experiment which is more
convincing than any attempt to accelerate the process. The limitations
of science, as well as its possibilities, is a recurring theme in all science
for conservation.
The assessment of durability is one of the unique contributions of
conservation science to the understanding of the chemical and physical
changes which affect materials. In many cases knowledge of materials
such as adhesives or varnishes is being gained which goes well beyond
the information available from the manufacturers or in publications of
scientists in academia. However, nowadays it seems that conservation
science places a rather low priority on materials and treatment. This fact
is demonstrated by the pie chart in plate 4. This sort of information has
previously not been available but is one of the outcomes of the data being
gathered for the 2013 ICCROM Conservation Science Forum in which UvA
will participate in conjunction with RCE, as partners in an international
event which seeks to be a defining moment in current state of development
and future priorities of the discipline.
The difficulties of scientific research to develop conservation treatment
methods have long been recognised. The situation was well described in
1982 by the late Giorgio Torraca, an Italian conservation scientist whose
understanding of conservation and the needs of conservator-restorers
was second to none. Torraca surveyed the role of conservation­scientists
28
29
in an article⁶ which should be essential reading for all conservator-restorers
and conservation scientists. His survey recounts an inauspicious start as
he describes the moment in 1818 when the renowned English scientist
Sir Humphrey Davy conducted experiments to unroll charred papyrus
scrolls from Herculaneum with the result that “one of the first recorded
attempts of scientists to meddle with the conservation of antiquities was
a complete failure”. Torraca held the view that conservation science in the
1980s had deviated from its primary task, to assist conservator-restorers
in preventive and practical treatments. He pointed out that reluctance on
the part of scientists to be involved in conservation practice often had the
consequence that conservator-restorers were compelled to take over all the
testing procedures involving experimentation, application and evaluation
of results. Provocatively, Torraca commented that “Occasionally conservator-restorers mask the lack of scientific grounding of their efforts by
contact with some friendly scientist who ­offers some amateur collaboration. The scanty and usually irrelevant results of such collaboration are
proudly displayed in reports and exhibitions to guarantee the scientific
level of the work done, on which they had no influence whatsoever.”
This is precisely the situation which the UvA C&R education in science
for conservation seeks to consign to the past. Building on conservatorrestorers’ increased competence as a result of the role of academic training
in conservation, especially in the last three decades, it is clear that an equal
dialogue between conservator-restorers and scientists becomes the norm
and, furthermore, that the necessity for embracing art history ensures a
true colloquy of not two but three interconnected disciplines. ■
Acknowledgements
The author is grateful for fruitful discussions over many years with many conservation scientists,
not least the authors of the articles cited. Particular thanks are also extended to colleagues from
the Municipal Museum in The Hague, the Rijksgebouwendienst (Dutch Government Buildings
Agency), the Belgian Building Research Institute, the International Centre for Conservation in
Rome (ICCROM), UvA C&R staff and students.
⁶ Torraca, “The Scientist’s Role in Historic Preservation with Particular Reference to Stone Conservation”, reprinted
in Historical and philosophical issues in the conservation of cultural heritage, Ed. Stanley Price, N.P., M. Kirby Talley,
Jr. and A. Melucco Vaccaro, Getty Publications, Los Angeles, 1996, pp. 439-444.
30
Summary’s
30
31
Abstracts of both Master’sand post-Master’s-theses
32
Klein maar fijn
Lead white in fine
particle size
33
[Marya Albrecht] This thesis focused on gaining more
insight into the use of lead white of fine particle size in
Dutch paintings of the 17th century, with the main question being the reason why painters used this very fine
grade of lead white. In order to be able to answer this
question, the available literature was studied and reconstructions based on historical recipes were carried out.
By combining knowledge of paint behavior with
practical experience gained by carrying out reconstructions, the specific properties of linseed oil paint in which
fine or coarse lead white particles are dispersed became
clear. Various series of reconstructions were designed, and
carried out, to deal with specific aspects of the working or
optical properties of the paint. The reconstructions have
been examined by taking cross sections and analyzing
them with optical microscopy and SEM.
These techniques were also used to analyze crosssections of several 17th century paintings that probably
contain fine lead white, amongst others Portrait of Hylck
van Eysinga by Wybrand de Geest and Still Life with
Flowers on a Marble Tabletop by Rachel Ruysch. ■
[Sanne van Bergenhenegouwen] This research includes a discussion
of the construction of movable books, largely based on the use of a
­case-study: the Meggendorfer-Collection at the BC, UvA in Amsterdam.
Included in this paper is a small terminology, designed to make discussion
of the subject easier and as unambiguous as possible. Attention is given
to the construction of the text-block, the paper used for the text-block,
the design of the mechanisms and the construction of the cover. Some
research has been done concerning the materials used for the paper by
means of fiber determination under the microscope. Distinction has been
made between seven types of mechanisms. A large part of the thesis is
concerned with the discussion of specific types of damage that occur in
relation to the movable book. This is divided into: damage to the textblock, damage to the mechanisms and damage to the cover. A distinction
has also been made between mechanical damage, damage caused by the
construction of the book, previous destructive restorations and natural
damage. A separate chapter is dedicated to the damage that is unique to
the Meggendorfer-Collection at the BC in Amsterdam. Several suggestions
are given concerning the treatment of the most frequently occurring
types of damage. A treatment proposal is given for the MeggendorferCollection, with special attention to the ethics concerning treatment of
the several restorative operations performed by the former owner of the
collection, prof. Wagenaar. These are for a large part responsible for the
unique character of the collection and should not be easily rejected. Care
has to be taken to preserve them, in light of the historical and cultural
importance of these treatments. ■
Acknowledgements
J. Boon, E. Oberthaler (Kunsthistorisches Museum Wien, Austria), J. van
Iperen (RMA), L. Megens (RCE), F. Ligterink (RCE), Z. Iddi, K.J. van den Berg
(RCE), J. Seynaeve, A. Wallert (RMA), A. van den Berg, K. Kirsch (RAA)
Acknowledgements
M. Wagenaar, T. Bruins, P. Verveen, G. Verhoeven, BC (UvA), M. Verheij
32
■ MA thesis 2012 (in Dutch) ■ MA thesis supervisors J. Schrijen (UvA), A. Balsem (BC, UvA)
■ MA thesis 2012 (in Dutch) ■ MA thesis supervisors E.E. van Duijn (UvA),
M.J.N. Stols-Witlox (UvA) ■ A paper on this work is in preparation
The construction and conservation
of movable books
A case-study of the
Meggendorfer-Collection at
the ‘Bijzondere Collecties’,
Amsterdam
34
Shining a light on
UV-adhesives
A research on the aging of
four UV adhesives in the field
of glass
34
The hand of a master
Art-technical research into the
painting technique of Jacob
Adriensz Backer (1608 / 9 -1651)
■ MA thesis 2011 (in English) ■ MA thesis supervisors M.J.N. Stols-Witlox (UvA), M. van Eikema Hommes (RCE)
■ Details of this research will be published elsewhere
■ MA thesis 2011 (in Dutch) ■ MA thesis supervisors K. van Lookeren Campagne (UvA), N.H. Tennent (UvA)
[Nienke Besijn] In the 1970s a new type of adhesive was introduced that
potentially could change the field of glass restoration forever: ultraviolet
light curing adhesive, also called UV adhesive. It has the ability to set
quickly which makes it more efficient than other adhesives used in glass
conservation-restoration. Now, 40 years later, the UV adhesives have only
sporadically been researched, and do seem to be applied often.
This study presents research on the history of UV curing adhesives in
glass conservation-restoration and how it is used today. With the help of
restorers who regularly use UV adhesive, four adhesives were selected for
further analysis: UV901 and UV902 (Sylmasta ®), Conloc 665 ® (EGO) and
Loctite 350 ® (Henkel). These adhesives were tested on their applicability
and reversibility on stable clear colourless glass. These tests were performed on broken microscope slides and wine glasses. The adhesives
were artificially aged by means of light aging equivalent to 100 years of
aging in museum conditions.
The applicability tests showed that all adhesives were applicable on
glass that is stable, clear and colourless. The most positive results in this
test were achieved with Conloc 665. The results of the tests for reversibility of the UV adhesives before aging showed that the UV adhesives
were removable using methylene chloride. After the artificial aging of the
adhesives the degree of yellowing was measured optically and spectrophotometrically. The overall results of the tested UV adhesives showed
no noteworthy yellowing, and the UV901 and UV902 showed no optical
yellowing at all. The results of the spectrophotometric measurement
also confirmed that the UV adhesives showed only minimal yellowing.
The reversibility tests on the aged adhesives showed that all four aged
UV adhesives were removable with methylene chloride. The aged adhesives were generally easy to remove, as opposed to the recently cured
adhesives. Applying acetone to the aged adhesives resulted in blistering
and stickiness, unlike the non-aged UV adhesives.
This research shows that the use of UV adhesives on stable colourless glass definitely has potential. The working time can be significantly
reduced and there does not seem to be any harmful long term effects on
stable colourless glass. Further research on different types of UV-curing
adhesives and the effect of these adhesives in other aspects of glass
conservation-restoration is recommended. ■
35
[Julia Maria van den Burg] Jacob Backer was a contem-
porary of Rembrandt, and of whom it was said he could
paint a portrait in one day. Until now, sporadic technical
research has been done on works by Backer, often within
the framework of other research projects. Little research
has focussed solely on Backer and his painting techniques.
This thesis studies a number of aspects of Backer’s painting techniques and working methods and places him in
the context of his fellow 17th century painters.
This thesis was written for the pilot Rembrandt Students
Project, conjointly run by the RMA, the UvA and the RCE.
Twelve paintings from different periods in Backer’s career
(early, middle and late) and with different subject matters
and sizes (large group portraits and smaller individual
portraits) from the RMA, the MDH and the AM were studied
in-depth with various techniques including visual analysis,
IRR imaging, x-radiography, cross-section analysis, SEMEDX and thread counting. Conclusions were drawn regarding the supports Backer used, the types of grounds he
painted on and the extent to which he used these grounds
in his final painted image, his use of preliminary drawings
and sketches, the style and presence under-drawing and
undermodelling, his painting technique and the development of his style throughout his career, and the types of
pigments used.
It was found that Backer used panels and canvases for
smaller individual portraits and canvases for larger group
portraits and classical and mythological scenes. Toward
the end of his career it appears that Backer only painted
on canvas, possibly following the 17th century trend
which saw a rise in popularity of canvas as a support.
36
Backer’s paintings reveal a traditional and economic
working-up of the paint layers. His brushwork became
looser and bolder as his career progressed and in the faces
and hands of the portrayed his brushwork contributes to
their plasticity. ■
37
Conservation dilemmas regarding
painted alterations to portraits which
are of historic value
Acknowledgements
A. Wallert (RMA), I. Verslype (RMA), G. Tauber (RMA), W. de Ridder (RMA),
L. Sozzani (RMA), P. Roelofs (RMA), Mauritshuis Den Haag, S. Meloni (MDH),
N. Middelkoop (AM), K. Kirch (RAA), A. van Loon (RCE), K. Keune (RCE)
Acknowledgements
N. Middelkoop (AM), G. Reichwein (AM), N. Renkema (Museum van Loon),
R. Ekkart, S. Meloni (MDH), G. Tauber (RMA), A. van Loon (RCE), F. Ligterink
(RCE), K. Kirsch (RAA), R.J. van der Maal, K. Keune (RCE), J. Pedroso (RMA),
S. van Oudheusden, A.A. de Tagle (Rce)
36
■ MA thesis 2012 (in Dutch) ■ MA thesis supervisor E.E. van Duijn (UvA)
■ A publication about this work is in preparation
Detail image of the
Portrait of Sara de Bie,
Rijksmuseum Amsterdam,
Inv. Nr. SK-A-3517
[Melissa Esther Daugherty] This Master thesis focuses
on problems around conservation-restoration methods
used on 17th century paintings that have been altered in
the course of time – with the emphasis on alterations that
affect the historical identification of the portrayed. The
conducted research centers upon two paintings from the
collection of the AM, portraits of Pieter de Graeff and
Jacoba Bicker both painted by Wallerant Vaillant. The
lead question is how to reach an objectively substantiated
decision regarding which stage in its history the painting
should be conserved to. The conservation-restoration
process of both portraits is documented in this thesis.
Using different methods of research (conservation
­documentation, interviews with experts in this field,
historic sources) and technical analyses of the paintings’
layer structure, more insight was gained into the time
frame and order of the various alterations. The conclusion
from these various forms of research is that a single answer
to the lead question cannot be given. The preferred
conservation-restoration method of alterations depends
on many different aspects. Therefore, reserved and reversible conservation-restoration methods should always be
preferred. They will allow future conservator-restorers
to make different decisions regarding the conservationrestoration of these painted alterations. ■
38
The paint box of Breitner and
the colours of Standage
Breitner could have been unaware of the risky combinations in his paint
tubes. Standage did not describe the particular fanciful names of paints
like Zinnober. Yet he clearly described the potential destructiveness of
lead white. Breitner consciously chose to paint with it, neglecting the
advice of a theorist. ■
■ MA thesis 2011 (in Dutch) ■ MA thesis supervisors M.J.N. Stols-Witlox (UvA), K.J. van den Berg (RCE)
■ A paper describing this work has been accepted for publication¹
[Hannie Diependaal] This study discusses Breitner’s paint box from
the collection of the AM (inv. nr. KA14285), which has not been described
previously. The research project focused on the influence that “The artists’
manual of pigments” published in 1886 and written by H.C. Standage
might have had on the artist George Hendrik Breitner (1857-1923).
­Breitner made a note of this manual’s title in his sketchbook around the
date of publication, but did the artist take the writers advice? The aim was
to gather knowledge on the object in its historical context, the artist’s use
of pigments and on 20th century oil paint. The study was undertaken as a
joint project by the UvA and the RCE.
The paint box was documented and samples were taken from the tubes
and palette within. Letters, notebooks and sketchbooks of the artist were
consulted to gather information on the use of the box and paint. The
findings indicate that the painter used and filled the paint box between
1897 and 1923. Shopping lists and names of colours as noted in the artist’s
black and white sketches reveal Breitner’s interest in new colours. This
impression is confirmed by the diversity of the 58 paint tubes in the box.
The paint comes from at least seven different colourmen. The majority is
labeled Claus & Fritz. Paint fabricated by this firm was considered to be
of a high standard and fine quality.
In his manual Standage describes pigments from a chemical point of
view. The author is an outspoken opponent of lead-containing pigments
on the palette. In this respect he distinguishes himself from contemporary
authors like the painter Vibert and the paint maker Keim who wrote
about pigments. In the opinion of Standage lead white is destructive.
He presents the combination of chromium yellow and cadmium yellow­
to demonstrate the adverse consequences of the interaction between
sulphur and lead.
In total 48 paint samples were taken from the paint box. These were
analyzed using complementary techniques: light microscopy and polari­
zation microscopy, SEM-EDX, XRF, FTIR, GC-MS and HPLC. The results
show that the colours in the tubes are composed of 20 different pigments,
in various combinations.
A few case studies were carried out that established some proof for
the relationship between Breitner and the tube paints. Results of XRF
analysis on several paintings dating past 1897 could be related to specific
combinations of pigments in the tubes. These included some of the
instable mixtures described by Standage. Lead white was identified in
all paintings examined.
¹ Diependaal, H., K.J. van den Berg, S. de Groot, M. de Keijzer, H. van Keulen, L. Megens,
“Breitner’s paint box and the colours of Standage”, Zeitschrift für Kunsttechnologie und
Konservierung, 2013, 1 (Spring).
39
38
Acknowledgements
G. Reichwein (AM), P. Born (AM), L. Wijnberg (SMA), M. van Bommel (RCE), S. de Groot (RCE),
M. de Keijzer (RCE), H. van Keulen (RCE), L. Megens (RCE), Ch. Caspers, J. Pedroso (RMA),
M. van de Laar (IC), F. Fahrenfort
Paint box of George Hendrik Breitner, (1857-1923),
collection Amsterdam Museum. (inventory nr. KA14258),
44,5 × 34,5 × 8 cm
40
Such objects do not respond to light aging as single entities.
Dilution of the medium and the existence of layers of media are
two aspects that play a role in light aging. A third very important
element is the role of a dye or pigment within the composition of
the object.
Furthermore, the investigation revealed that the theoretical
model is not adequate for determining the sensitivity to light and
possible damage to the object because the model ignores lightsensitive variations in the objects.
Further research could lead to refinement or modification of
the current model. The basis of this model would no longer be the
ISO classification based on an object group, but on the different
­components of an object and the mutual coherence of these components. An evaluation of each part of an object should form the
basis for the determination of the risk of light damage per item. The
light sensitivity of the most important components of the object
would then form the basis for determining the ISO rating. ■
Light damage on paper objects
with coloured media
Towards a differentiated
sensitivity classification
■ MA thesis 2010 (in Dutch) ■ MA thesis supervisors B. van Velzen (UvA), J. Schrijen (UvA), F. Ligterink (RCE),
B. Reissland (RCE) ■ The thesis (in Dutch) is available free of charge¹
[Judith Geerts] Light causes damage to materials, and there-
fore it forms a dilemma for museums and other institutions that
manage collections when they wish to exhibit their collections.
Guidelines for the exhibition of objects have been formulated in
the past in order to restrict damage caused by light as much as
possible. These guidelines are based on the sensitivity of an object
in relation to luminosity and exposure time.
The sensitivity of an object is determined by an ISO classification known as the ‘blue wool standard’. The limitation of this
classification in sensitivity classes is that objects are classified
based on the type of object. Work on paper with coloured media
is classified as ISO 1, very light sensitive. The classification does
not consider the various components of an object and how these
components change under the influence of light. There is no
knowledge about the effects of various changes in these individual
components to the appearance of an object as a whole. As a
consequence, the classification in sensitivity classes only presents
a general picture. The sensitivity of specific objects may therefore
be overestimated or underestimated.
In order to obtain a better understanding of the damage caused
by light a study was conducted into the effects of light aging on
the appearance of works of art on paper with coloured media.
­Reconstructions of three typical objects were made: a watercolour
painting, an ink drawing, and a piece of wallpaper. The reconstructions were exposed to light over a period of seven weeks
with an actual total exposure time of 830 hours at an average of
11,000 lux. The objects were scanned, and colour measurements
were taken every 24 hours. A theoretical model was developed
based on the current guidelines for exhibiting collections, as
formu­lated by the ICN. The results of the scans and colour measure­
ments were analysed and compared to the theoretical model, and
led to the conclusion that for objects in the category ‘work on
­paper with coloured media’ a closer look at light aging is required.
¹ http://dare.uva.nl/document/478509 (21-03-2013).
41
Acknowledgements
B. Wei (RCE), I. van Leeuwen (RMA)
40
42
A study of 18th century
furniture locks
Acknowledgements
R. Kievits (RCE), P. van Duin (RMA)
¹ http://dare.uva.nl/document/469714 (21-03-2013).
42
[Sophie Glerum] Although a wide variety of varnishes and coatings
has been used in the 19th century, we nowadays are mostly familiar with
the appearance of a shellac based French polish or a wax coating, being
the coatings that have been used in conservation-restoration for the last
hundred years. To obtain better knowledge on the coatings which were
available during the 19th century, research has been carried out regarding
the recipes and instructions appearing in Dutch, French, German and
English written sources from the period 1800-1900. During the selection
process only the recipes and instructions were selected that dealt explicitly
with the finishing of furniture or wooden objects.
Based on the information that was found during this research, twelve
coatings were selected and reconstructed according to the original recipes
in order to get an idea of their original appearance. The following selection
was made: three oil varnishes, four alcohol varnishes, one varnish based
on oil of turpentine, two French polishes (one of which was made in two
different solutions) and two wax polishes (which both had a variation
in composition, so in fact four wax polishes). These coatings were
­prepared according to the found recipes and were applied according to
the original instructions to test samples of mahogany veneered multiplex
of 24 × 40 cm.
The tests also included the possible effect of two often applied precoating wood preparation techniques, addition of a layer of a) diluted
glue size or b) drying linseed oil. After the coatings were applied and
finished an impression was obtained of the intended appearance of the
original coatings and the way in which they differ from the coatings
we are used to see nowadays. ■
Acknowledgements
H. van Keulen (RCE), P. van Duin (RMA), A. Coerdt (RMA), I. Breebaart (RMA), R. Kievits (RCE),
K. Padding (MVP)
PD Res thesis supervisor S.M. Nijhuis (UvA)
ration, a conservator-restorer frequently encounters materials that cannot
be categorized as wood, but still sometimes require special attention in a
conservation-restoration process. Furniture locks are prime examples of
such materials. Furniture locks can contain important clues with respect to
dating and the country / region in which the object has been manufactured.
Next to this, one can also question the authenticity of a certain lock on a
piece of furniture. The metal lock is a key point of attention, for the following reasons:
- locks can be worn out (replacement / restoration of parts may be important);
- locks may have been replaced or removed (the authentic configuration
has disappeared);
- the lock has to be conserved.
In spite of their importance, furniture locks are an area in which little research
has been done. The characteristics of various locks from various periods in
history are only sporadically found in literature but have not been subject
of a systematic investigation. As a result, it is very difficult to establish
if an object is authentic or not. Also, metal parts like furniture locks are
often sent to a conservator-restorer specialized in metals. Obviously, if
the knowledge of the metal components would assembled and suitably
organized, a specialized furniture conservator-restorer would be able to carry
out a restoration on his own, and to establish whether a lock configuration
is authentic or not.
For these reasons it was decided to assemble and organize systematically
all information about the most common locks on furniture that a specialized
wood / furniture conservator-restorer regularly may encounter.
A documentation system has been set up, including drawings and technical
specifications of all 18th century furniture locks, the materials, tools and
techniques that were used to manufacture them, and the techniques and
materials used to attach the locks to the furniture. This system allows the
selection of an appropriate lock for a piece of furniture at which a lock is
missing, or to make a copy of the lock.
Also, an authenticity justification procedure has been set up, based on the
applied lock-manufacturing techniques, and traces of manufacturing tools
and attachment material on furniture. ■
Finishes on furniture 1800 -1900
Reconstructions of 19th century finishes
on the basis of contemporary sources
PD Res thesis 2012 (in Dutch)
■ MA thesis 2011 (in Dutch) ■ MA thesis supervisors H. den Otter (UvA),
T.C.P. Beentjes (UvA) ■ The thesis (in Dutch) is available free of charge¹
[Auke Gerrits] In the discipline of wood / furniture conservation-resto-
43
44
45
Detail of ornaments on a 19th century
composition frame, courtesy of
Rijksmuseum Twenthe. Inv. nr. 0138
Original gilding on nineteenth century
composition frames
Research on historical
gilding techniques
■ MA thesis 2012 (in Dutch) ■ MA thesis supervisor
S.M. Nijhuis (UvA) ■ Details of this research will be published
elsewhere
[Tess Graafland] In the 19th century a large amount of frames
was made out of ‘composition’, a dough-like material that consists
mainly out of chalk, glue, linseed oil and a filler such as saw-dust
or paper. This blend of materials was pressed into a mould to form
ornaments which were glued on the frame. Finally, the frames
were completely gilded. Due to the popularity of these frames
and the increasing industrialization, there was a large production
of composition frames in the second half of the 19th century.
Nineteenth century composition frames have been analyzed
mainly from an art-historical point of view, focusing on function,
style, type and the development of various types of frames. The
gilding of these frames has not yet been investigated extensively,
and this applies in particular to gilded composition frames that
44
were made in The ­Netherlands. For this reason, research was
started to gain more insight into the 19th century Dutch gilding
techniques, using five 19th century composition frames from the
RMT (Enschede, The Netherlands) as a case study.
To verify expectations concerning the type of gilding used and
the layer structure of the gilding, Dutch, English and German
historical sources from the second half of the 19th century were
analyzed for specific regulations and prescriptions for the ­gilding
of the frames. Cross sections of the five above-mentioned composition frames were taken and analyzed with light microcopy, and
later on with FTIR and SEM-EDS to identify ­organic and inorganic
materials, respectively.
The relatively small number of historical sources and frames
that has been studied in combination with and the limited technical data do not allow yet a definite conclusion ­concerning gilding
practices in the 19th century in The Netherlands, but it has become clear that both historical recipes and technical analyses are
needed in order to avoid premature conclusions. ■
Acknowledgements
Rijksmuseum Twenthe (RMT), G. Kingma (RMT), H. Baija (RMA), K. Keune (RCE), J. van
Iperen (RMA)
46
Organic moulding material in lost wax
casting in 16th century Italy
47
The toxicity of the pigment orpiment
in historic interiors
■ MA thesis 2012 (in Dutch) ■ MA thesis supervisors D. van Kempen (UvA), R. Keppler (UvA, IC),
L. Megens (RCE) ■ A paper has been accepted for publication¹
■ MA thesis 2012 (in Dutch) ■ MA thesis supervisors J.E. van Reekum (UvA), T.C.P. Beentjes (UvA)
[Jeroen van Halder] In his 1568 publication Giorgio Vasari claimed that founders who
used the lost wax method were able to cast bronze statues so perfectly that these statues
did not need any correction of casting defects once they were cast. This was the main
reason to focus on the moulding materials used in lost wax castings in 16th century Italy.
The main component of these mould materials was clay. The lost wax method for casting
bronzes is still in use today. Onto a wax model a sprue, feeding channels (runners) and
venting channels are placed, and covered with a heat-resisting moulding material. By
heating the mould the wax is removed. Subsequently, the mould is fired after which the
bronze is poured into the cavity of the mould. Finally the mould is broken into pieces,
and casting defects, if any, can be corrected. When casting bigger objects, which have to
be casted hollow, an inner core is used.
Not a lot of recent research on Renaissance moulding materials is known to exist.
The main two recent sources of information are that of Francesca Bewer and Jane Basset.
Within this thesis the focus is in particular on the main Italian sources: Biringuccio, Cellini, Gauricus and Vasari. The main moulding material used by them is earth containing
clay, mixed with wool-cloth clippings. Other additives named by various authors are:
horse or cow manure, hair, hemp, flax, straw, crushed brick, ashes, sand, salt water, iron
scale, ashes of young ram’s horn and plaster. The two most important sources are the
publications of Biringuccio and Cellini. They go into greater detail describing the earthy
clay they use as main moulding material. The descriptions by Cellini are even more
valuable because he reports relative proportions of the materials used and gives a detailed
account on how to use them. The main components clay /earth and wool-cloth clippings
have been studied in more detail. It can be concluded that several authors were not quite
accurate in their translations and interpretations of these main components. Modern
standardization allows for a more precise definition of the various terms for clay, earth,
loam and sand.
As to the experimental side of the research, a few small tests were carried out with
moulding material based on clay with one or more additives. River clay mixed with wool
fibres resulted in an inadequate outcome. A loam-mixture of sand, clay, goat hair, horse
manure and reclaim, obtained from the Whitechapel Bell Foundry London UK, delivered
good castings. These equalled casting results made with modern day moulding materials.
In order to get a perfect cast the moulding material is most important but many other
factors influence the outcome, e.g. the composition and temperature of the alloy, the
process of firing the mould and the craftsmanship of the foundry men. Concluding: casting bronze statues so perfectly that they do not require any correction of casting defects
is possible but only under ideal circumstances. ■
[Jessica Hensel] Anyone that handles old, deteriorating paint layers, e.g. con-
servator-restorers and museum employees, must always consider the possibility
that on the surface of the paint toxic pigment particles can be present that may
come loose when being handled. An inspection of the condition of deteriorating
paint layers, and detection of potentially toxic materials on the surface, should be
carried out before any treatment.
Recently, two deteriorating painted ceilings in a 17th century monument in
Hoorn ( The Netherlands) have been examined. In the paint on both ceilings
orpiment (arsenic sulfide, As2S3) and its toxic oxidation product (arsenic oxide,
As2O3) have been identified using PLM. The presence of arsenic has been confirmed with XRF.
The toxicity of orpiment is known since antiquity, due to the highly toxic element arsenic. The precise hazards of the presence of orpiment and arsenic oxide
to both the conservator-restorer of the ceilings and the resident of the monument
were unclear and therefore two experiments were carried out.
An indication of the risk for the conservator-restorer has been obtained by
measuring the exposure to arsenic in inhalable dust during an 8-hour experiment.
In this experiment the overpainting on one of the ceilings was mechanically
removed using a scalpel. During this experiment a special gas mask with a filter
was worn. Afterwards, the contents of the filter were analyzed with inductively
coupled plasma mass spectrometry (ICP-MS). The ICP-MS results indicate a presence
of arsenic in air that exceeds the threshold limits of several European countries.
The risk for the resident has been assessed by examining the condition of the
unvarnished paint surfaces, the migration of arsenic in the paint layers and the
wooden substrate (using SEM) and the detection of arsenic particles in dust (XRF).
Several measures are recommended to reduce exposure, such as improved
ventilation, shorter working hours per person, the development of a different
removal method and the use of appropriate protective equipment. During hands-on
work, contact with inhalable dust must be avoided as much as possible. A protocol
has been established for the handling of paint layers in historic interiors or on
historic objects that might contain toxic pigments. ■
Acknowledgements
P. Meijers (Monumentenzorg, Hoorn). M. de Graaf (UvA), J. Pedroso (RMA), K. Keune (RCE), A. Wallert
(RMA), J. van Iperen (RMA), E. Geldhof (BTC)
Acknowledgements
R. van Langh (RMA), A.A. de Tagle (RCE), A. Reijnders, R. Ruimer, F. Bewer, Whitechapel Bell Foundry London UK,
M. Ibsen, K. Ravn Hedegaard
46
¹ Hensel, J., (2013) The toxicity of the pigment orpiment in historic interiors. Paper presented at:
“Conservation-Restoration and Health / Security of people and the environment”, Colloque 17-21 juni 2012,
Draguignan-Figanieres, France. http://art-conservation.fr/colloque-2013/ (20-02-2013).
48
[Annemieke Heuft] In February 2011 the restoration of the large organ of the
Westerkerk in Enkhuizen was completed. Architectural paint research on the
wooden case had uncovered remains of an original finish from 1549 and a 17th
century painted decoration under the current black-and-gold exterior dating
from 1838. After analyzing the black paint it appeared to be composed of coal tar
in linseed oil and colophony resin. Continuing on the restoration, this thesis is a
study of this coal tar paint, its material-technical context and the historical usage
of coal tar as an ingredient for paints applied by house and furniture painters in
the 19th century.
Coal tar is a ‘bituminous material’ and has been put in relation to asphalt.
Since the 18th century it was gained as a by-product in the carbonization of
coal to make cokes. Studying 18th, 19th and early 20th century housepainters
manuals and recipe books, it appears that bituminous materials like asphalt,
tars and pitches have been used in enamel paints, varnishes and lacquers for a
variety of objects. Coal tar was also regularly used as a protective layer on coarse
wood exposed to water, particularly in the ship-building industry. Because of its
wide availability it has been frequently sold as a cheap substitute for the natural
asphalt that had to be imported from the Middle East. This has had its consequences for the paints made with the cheaper material. Scientific research has
suggested that coal tar has an even greater influence on the drying of linseed oil
than asphalt, and that paints made with coal tar dry very slowly or never at all.
Despite of this the coal tar paint on the organ case in Enkhuizen has aged quite
well, although the slow drying has been responsible for the formation of drying
cracks in the gilded decorations applied on top of the black paint.
Why it was decided to use coal tar on the organ case in Enkhuizen could not
be made absolutely clear, but it probably will be related to its deep color and
delicate gloss.
Although the historic sources suggest that bituminous materials have regularly been used as a painting ingredient on other objects than paintings, other
painted finishings comparable to the one on this organ have not been found during this research project. Possibly other bituminous paint layers on objects have
not been preserved, or other black paints consisting of these materials have not
been identified before. Black was used more often in interior decoration around
1838, mostly to imitate Japanese or Chinese lacquer panels on the walls, and
black furniture in one’s interior was considered distinguished and genteel in 19th
century Holland. The gentility of the color black in the Dutch organ tradition
was primarily popular for the more conservative organs and applied by a few
specific organ-builders in the protestant reformed communities in the northern
provinces of The Netherlands: Groningen, Friesland and the north of NoordHolland. In these regions the use of coal tar could be connected to ship-building,
or to a traditional paint recipe of a specific painter or organ-builder. ■
Detail of cracked
gilding on coal tar
containing paint
on the left shutter
of the organ in
the Westerkerk
Enkhuizen
Acknowledgements
R. Lijnsvelt (Stichting Westerkerk Enkhuizen), R. Keppler (IC), M. de Keijzer (RCE), L. Megens (RCE), H. van
Keulen (RCE), G. Tauber (RMA), N. van der Woude (SRAL), E. Geldhof (BTC), B. Jonker (IC), M. Polman (RCE),
E. Winkel (Flentrop Orgelbouw)
48
■ MA thesis 2011 (in Dutch) ■ MA thesis supervisors D. van Kempen (UvA), R. Jongsma (RCE)
Coal tar as a painter’s material
A material-historic study of a 19th century
coal tar paint on the organ case in the
Westerkerk in Enkhuizen
49
50
Go with the glow
Treatment options for a work of art
with a phosphorescent paint layer
PD Res thesis 2012 (in Dutch)
50
try to manipulate the phosphorescent pigments and paints to find a suitable
retouching medium.
Practical and technical tests where carried out to find a retouching
medium that resembles the original paint layer in daylight and also has a
comparable emission spectrum. ■
Acknowledgements
G. Kingma (RMT), P. Knolle (RMT), H. Offerhaus (UT), J. Westerik (UT), D.J. Dikken (UT), K. Keune
(RCE), S. de Groot (RCE), U. Beerhorst, A. Colombini (CICRP Marseille), M. Martindill (Artemis UK),
Y. Takeshima (Nemoto Europe BV), R. Brust (Brenntag Nederland / Lumilux), A. Vredenborg,
J. Goezinne, P. Keune, A. van Ravesteyn, T. Oostendorp, M. de Visser, C. Kordes (Stedelijk Museum
Schiedam)
Reconstruction of ripple mouldings
■ MA thesis 2012 (in Dutch) ■ MA thesis supervisor S.M. Nijhuis (UvA)
PD Res thesis supervisors I. Smit (RMT), L. Beerkens (SRAL)
[Ellen Jansen] Phosphorescence is a complicated phenomenon. It is
a form of photoluminescence that is associated with electrons in a
­triplet-state. This means that the spin of the excited electron changes
and therefore it returns slow(er) to an available lower-energy orbital.
When returning the electron releases energy that we observe as light.
Since this is a process that takes a long time, the phosphorescing object
continues to glow in the dark.
The phosphorescence in art materials is achieved by pigments. For this,
mostly phosphor zinc sulphide and rare earth pigments are used. Both type
of pigments have different characteristics, but comparable degradation
symptoms when exposed to UV-radiation, water and acids. When the pigments
are used in phosphorescing paints, the phosphorescent pigment, the medium,
the pre-treatment of the pigment and the filling materials determine the
characteristics of the paint. The information that the manufacturers release
about the mixing of phosphorescent paint was combined with results from
practice-oriented research. This helped to create more understanding about
the characteristics of phosphorescent paint and how it can be manipulated
for our own purposes.
From the 1960s onwards, ‘stable’ phosphorescent art materials are available and many (known) artists have used them. The artwork Without Title
(1968) by Rainer ‘IMI’ Giese (Neheim-Hüsten, 1942-1974) from the collection Depot VB / VR of the RMT (Enschede, The Netherlands) is an example
of a phosphorescent artwork. It consists of two beams painted with yellow
phosphorescent Wiedelux paint. In daylight the paint looks yellow and in
the dark it has a yellow-green afterglow.
Over the years, slowly a discrepancy has arisen between the original idea
of the artist and the condition of the artwork. Giese created rigid geometric
forms that give the illusion of a large spaciousness because of the phosphorescent finish. On the surface several damages can be recognized that hinder
the phosphorescence of the artwork and can be seen in the dark as black
spots. A conservation strategy was conceived for each specific ­damaged area.
The retouching of the lacunae in the phosphorescent paint layer proved to
be the biggest challenge.
Technical analysis determined that the original phosphorescent paint
layer was cadmium based. Since cadmium cannot be used anymore for the
production of phosphorescent pigments because of health and safety
­regulations, the materials that are available on the market now have different
properties than the material that Giese used. Therefore, it was necessary to
51
[Thijs Janssen] The conservation-restoration of ripple mouldings is often
problematical. Traditional methods are either too expensive or too inaccurate.
In order to find alternatives, the applicability of computer operated techniques for the reproduction of ripple mouldings has been investigated. This
exploratory research concentrated on the accuracy of accessible ­techniques
for milling and printing. A 17th century cabinet served as a case study. In
order to make an accurate reproduction, the characteristics of one of its loose
ripple mouldings was established. Accessible production techniques were
selected with the help of Fablab, an organization that ­investigates and offers
computer-operated techniques.
Two methods have been used for the reproduction of a ripple moulding.
A routing technique with a three-axial milling machine and, secondly, a
technique for 3D printing followed by Fused Deposition Modelling. In ­order
to test these techniques, a contact 3D scanner was used to generate a 3D model
of the ripple moulding. The milling machine has proven to be an accurate
method, but to allow for actual production, some additional research has to
be carried out. The method used for Fused Deposition Modelling did not
deliver the required accuracy and it was also not possible to give the material
a satisfying finish. Some alternatives are proposed that can be tested. The
applicability of the computer operated production techniques is also limited
by the scanning method. The contact scanner is not mobile so ripple mouldings that are fixed on a cabinet cannot be scanned but alternatives to this
technique are proposed. ■
Acknowledgements
Museum Rotterdam (MR), K. van Gelder (MR), M. de Visser (MR), C. van Soestbergen, Hout- en
Meubileringscollege Amsterdam, Fablab Amsterdam (FA), B. Withagen (FA), Fablab Maastricht
52
Vergipsing: a specific damage
on parchment bookbindings
different causes. An exceptional appearance of damage is called ‘vergipsing’. The Dutch term – technically a misnomer meaning literally
‘to become plaster’ – was coined in an attempt to qualify the process
of parchment becoming fragile and brittle at places displaying tension.
The contaminated parts often appear to be grayish in color. This kind of
damage is predominantly detected on the book’s spine, customary the
section of the binding most frequently exposed to external influences
of light, air pollution and dust.
It seems evident that the term ‘vergipsing’ has been used in different
settings. On one hand the current state of research describes the occurrence of ‘vergipsing’ as a result of the absorption of sulphur dioxide from
the air interacting with the calcium carbonate present in the skin thereby
producing calcium sulfate, otherwise known as gypsum. However to
no extent evidence actually demonstrated the presence of gypsum in the
parchment. On the other hand conservator-restorers use the term ‘vergipsing’ when the parchment becomes brittle, resembling the physical
properties of gypsum.
Outside The Netherlands no specific term for this phenomenon is
known. Possibly ‘vergipsing’ in itself is not recognized as a particular
type of damage. Preferably one should speak about the physical state of
the parchment, rather than about ‘vergipsing’.
Today’s bookconservator-restorer is not inclined to handle ‘vergipsing’
on parchment bookbindings to prevent additional damage and the
potential loss of material. To date no set procedure for the conservation
of ‘vergipst’ parchment has been developed. The lack of guidelines may
result in deleterious handling of the afflicted area and even the irrecoverable detriment of precious antiquities.
Once the bookconservator-restorer has decided to attempt to conserve
‘vergipst’ parchment a number of problems may occur: the parchment
can become gelatinous if the glue contains too much moisture, difficulties
with the compatibility of the new backing with the old parchment may
occur and, perhaps most obviously, the ‘vergipst’ parchment is terribly
vulnerable to breakage due to its brittle nature.
In lieu of this hiatus in understanding the cause of ‘vergipsing’, this
research hopes to provide a potential conservation methodology making
use of the appropriate adhesive and backing. For glueing ‘vergipst’
parchment, Plextol D360 appeared to yield the best results of all glues
tested in this research. The flexible adhesive gives a solid suture and
¹ Keller, R., Journal of Paper Conservation 2011, vol. 12 – nr. 4, “Degree Works”.
52
does not seem to deform the substrate. As a suitable backing both new
vellum and Tyvek were tested. Both materials displayed advantages and
­disadvantages and can be utilized for different kind of applications. The
two materials are stable, but the degraded parchment seemes to have a
better adhesion with Tyvek. From an aesthetic point of view however,
it is more obvious to use vellum, providing that the colour is similar to
the old parchment. Consequently in regard to the use of an appropiate
­backing, this research does not provide a conclusive answer. ■
Acknowledgements
K. Scheper (Universitaire Bibliotheken Leiden), P. Hoftijzer (Universiteit Leiden), C. Duran
Casablancas (Stadsarchief Amsterdam), R. van Gulik (Teylers Museum Haarlem), H. Porck
(Koninklijke Bibliotheek), R. Larsen (School of Conservation, Copenhagen), A. Ames (RMA)
The filling-in of gaps in transparent
finishes on wood using polymeric films
■ MA thesis 2011 (in Dutch) ■ MA thesis supervisors S.M. Nijhuis (UvA), D. van Kempen (UvA),
H. den Otter (UvA) ■ Details of this research will be published elsewhere
■ MA thesis 2011 (in Dutch) ■ MA thesis supervisors J. Schrijen (UvA), E. Nijhoff Asser (IC)
■ This abstract has been published previously¹
[Rachelle Keller] Deterioration and damage to parchment may have
53
[Diederik Kits Nieuwenkamp] If a gap in an aged transparent coating
on wood with surface texture (craquelure) is filled properly, the aesthetic
value of the object will increase and the old finish with its historical value
and patina can be preserved.
The aim of this study was to explore possibilities to fill up such gaps
using exteriorly formed polymeric films. In the process of selecting
­appropriate substances for such a film, key selection criteria are safety
for the object and the conservator-restorer, and features like texture,
­saturation of the surface, the gloss and the thickness of the film used
and adhesion.
Film-forming qualities were tested for a set of commercially available
synthetic resins. To obtain films with an aged-looking texture, a silicon
mould was used. Additionally, several ways to manipulate the optical
properties were tested.
The conducted experiments showed that the physical and optical
properties of the film are mainly determined by the choice of resin. The
films of resins with a low molecular weight turned out to be too brittle
to handle. However, two other resins led to manageable and transparent
films and, advantageously, both can be dissolved in ethanol, a solvent
with minor health risks. The experiments also revealed that gloss is
determined by the texture of the mould and can also be influenced by the
solvent in which the resin is dissolved or by which the film is reactivated.
Several techniques have been developed to temper the gloss. The thickness of the film can be influenced by its mode of application. Saturation
54
Study of agents that cause foxing
on Japanese style paper
■ MA thesis 2012 (in Dutch) ■ MA thesis supervisor B. van Velzen (UvA)
[Roosanne Kliphuis] Foxing, the occurrence of brownish spots on old paper, is
well known for its disturbing appearance and in paper conservation-restoration
from the 1930s on a lot of research has been carried out to sort out this problem.
However, foxing on Japanese style paper, an important and widely used type of
paper, has hardly been investigated. Since Japanese style and Western paper differ
in composition and manufacturing process, the results of the foxing research of
Western paper do not necessarily carry over to Japanese style paper.
The Dutch artist Carel Visser has made a set of woodblock prints on Japanese
style paper that has various foxing problems. The foxing has been investigated by
tracing back the context of the prints, examining them with analytical techniques,
executing an experiment and reviewing relevant literature. The most important
conclusion is that iron is likely to induce foxing in Japanese paper by oxidation
and migration processes while the role of environmental conditions is probably
much smaller. ■
Acknowledgements
F. Ligterink (RCE), D. Christoforou (RMA), P. Clement, M. Jürgens (RMA)
54
Understanding historical recipes for
the modification of linseed oil
An experimental study into the properties of
modified linseed oils for use as binding media
in early northern European panel painting
Invited contribution (Dept. of Art History, UvA)
■ MA thesis (Dept. of Art History, UvA) 2012 (in English) ■ MA thesis supervisors A. Vandivere (UvA),
A. Wallert (RMA, UvA) ■ Details of this research will be published elsewhere¹ ²
of the colour of the wooden surface can be determined by the choice of
the resin with which the film is attached.
The film can be attached to the original finish using the same resin
from which the film has been made. In this way the extra work is limited
and the composition as a whole remains relatively simple. An experiment
involving the bond strength showed that the adhesion to undamaged
wood is more than sufficient. However, in practice also the physical state
of an object and its material composition have to be taken into account
when choosing a resin and solvent.
The above-described technique has already been applied successfully
to an object. It seems to be a useful addition to the existing repertoire
of possibilities to fill gaps in (damaged) wooden surfaces that have a
transparent, aged finish. It gives the opportunity to use materials that are
known for their stability. The optical properties, the thickness and the
texture of the film can be adjusted to the gap and the surrounding original
surface. Since the film formation does not take place on the object, the
risk of damaging the object is minimized. The technique is relatively
simple to carry out and no special measures are needed, which makes it
a suitable technique to use in private restoration studios. ■
55
[Indra Kneepkens] Late medieval technical sources contain an array
of procedures aiming at the modification of linseed oil for use as binding
media in late medieval panel painting. Although the benefits of such
modified oils are sometimes briefly described in the recipes, it is not
always easy for the modern day reader to understand their exact meaning
and application.
To gain a more profound understanding of late medieval recipes for
the modification of linseed oils, a selection of recipes, each representing
a particular category of binding media, was tested. A raw linseed oil that
formed the basis of all other oils was compared with a washed, a sunthickened and a boiled variety. Furthermore two oils were prepared in
which a combination of amber and colophony had been dissolved and
another one that had been boiled with pumice powder and bone white
and to which zinc sulfate was added as a dryer. The resulting binding
media were tested with different pigments and different application
techniques. During and after application, the handling properties, drying
time and appearance of the paints (before and after a period of artificial
ageing) were analyzed and compared. Interestingly each of the different
binding media turned out to have its specific affordances and weaknesses,
depending largely on the choice of pigment and application technique.
A sample of each binding medium was also studied with Thermally
assisted Hydrolysis and Methylation GC-MS in combination with
Curie Point pyrolysis, to get an idea of differences in oxidation and
­polymerization as a result of the applied modification methods. This
information was used in a preliminary attempt to understand the differences between the properties of the oils. Considering the extra expenses
and trouble of preparing modified linseed oils, including terrible stench
¹ Kneepkens, I., A. Wallert, R. de Jongh. “A substance which serves all paints” In: Making and
transforming art: Changes in artists’ materials and practice. Proceedings of the 5th Interim meeting
of the ATSR ICOM-CC workgroup, Archetype, London. 2013. Accepted for publication.
² Kneepkens, I., J. Dik, K. Keune, G.V. van der Snickt, A. van Loon. 2013. To be submitted.
56
and the risk of explosion, an estimation was made of the likelihood
that some of these binding media would indeed have been used for late
medieval panel painting.
Because of the extreme variety in properties that was found, this
research supports the idea that perhaps a much wider variety of modified
oils was used in late medieval painting in general, and even in single paintings, than we have so far been able to identify. Therefore, a more structural
binding medium analysis is recommended in which the application technique and choice of pigments are considered key elements. ■
57
Flaunting ostrich feathers
Research on the yellowing
of white ostrich feathers
Acknowledgements
J. Pedroso (RMA), K. Keune (RCE), S. de Groot (RCE), Amsterdam Museum (AM), L. Wurfbain
(AM), L. Sterenborg (AM), A. Rae, J. van Iperen (RMA), M. Reuss, N. Bloemberg, J. van den Berg,
Struisvogelboerderij Monnikenwerve Sluis, L. Hanssen, S. Meijer (RMA), M. van Bommel (RCE),
A.A. de Tagle (RCE), E. de Groot, L. van Ravels
Technical tests in lead white (top row), madder lake (second row), verdigris (third row) and
azurite (bottom row) with raw linseed oil, washed linseed oil, sun-thickened linseed oil, boiled
linseed oil, amber-colophony varnish, fused amber-colophony varnish and oleum preciosum
(from left to right)
56
■ MA thesis 2012 (in Dutch) ■ MA thesis supervisors R. Lugtigheid (UvA),
J.P.B.M. de Vries (UvA), R. Peschar (UvA)
[Marjolein Koek] The conservation and restoration of ostrich feathers
usually focuses on the removal of dust and /or dirt particles on the feather
and the consolidation of fractures in the feather shaft. Until now the
problem of discoloration in the form of yellowing on white (ostrich)
feathers has not been described as such. This research focuses on what
causes this discoloration on white ostrich feathers and how the yellowing
may be reduced or even removed. The study is relevant for conservatorrestorers of (ostrich) feathers, possibly in combination with textiles or
other materials, in which the damage to feathers in the form of yellowing
is visible.
A ball gown with a collar of ostrich feathers acted as a case study and
determined the framework within which the research took place. Some
yellowed feather material that already had come loose was used as reference in the analyses. White ostrich feather sample material was artificially
aged under various conditions (light, temperature and relative humidity).
All samples were analyzed with microscopy and FTIR. Various solvents
were tested for their effectiveness at reducing or removing the yellowing.
The accelerated aging results show that yellowing can be induced by both
light and temperature / humidity. Furthermore, the physical structure of
the white ostrich feathers and the optical reflection of light by the white
‘color’ influence the perception of discoloration. The ideal treatment has
a low ‘intensity’ (i.e. the treatment is reticent), stabilizes the conditional
state of the object, and the treatment provides visual improvement to the
object. Considering these aspects, treatment with a deionized water rinse
is the most suitable choice found so far. ■
Acknowledgements
A.A. de Tagle (RCE), R. de Jongh, S. Neven, H. van Keulen (RCE), K. Keune (RCE), K.J. van den Berg
(RCE), J. Pedroso (RMA), S. de Groot (RCE), M. van Bommel (RCE), F. Ligterink (RCE), M. de Keijzer
(RCE), K. Padding (MVP), H. Baija (RMA), A. Pappot (RMA), J. van Iperen (RMA), M. van der Laar (IC),
I. Rijkers, H. Neevel (RCE)
58
In the clouds with Willem Beurs?
A study into the value of De Groote Waereld
in ’t Kleen Geschildert […] (1692) by Willem
Beurs as technical art history source
Waereld in ’t Kleen Geschildert […] (1692), a treatise on the practise of
oil painting written by Willem Beurs, as an art technological source. The
relatively unknown Dutch painter Willem Beurs described in his treatise
‘general’ practical information including the preparation and use of various
pigments and colorants, the preparation of canvasses and panels and the
various brushes a painter could use. The largest part of the treatise consists
of specific instructions for depicting all kinds of subjects, in which Willem
Beurs mainly indicates which pigments and colorants the painter should
use and how every subject should be build up. Even though several links
between the contents of De Groote Waereld in ‘t Kleen Geschildert […] and
actual professional painting practise in The Netherlands have been proven
to exist in the past, there still is a lot of uncertainty concerning the value of
the treatise and the work is not yet generally acknowledged as an important
contemporary source on the art of oil painting in the Northern Netherlands
in the 17th century. This uncertainty has been the main reason for setting up
a research project.
This thesis can be divided into two sections. Within the theoretical
part of the research Willem Beurs’ ‘general’ practical information has been
thoroughly analysed and the treatise was placed within the 17th century
tradition of writing on the Dutch art of oil painting. This has shown that
De Groote Waereld in ‘t Kleen Geschildert […] can be considered rather
unique in terms of structure and furthermore that the treatise contains
­interesting and exclusive information regarding the pigments and colorants
that were in use in The Netherlands during the 17th century.
Within the technical part of the research paintings were analysed to
determine to what extent Willem Beurs’ specific instructions for painting skies
in land- and seascapes can be considered a reliable reflection of the actual
17th century painting practise in the Northern Netherlands. Nine land- and
seascapes by the painters Ludolf Bakhuysen (1630-1708), Jacob Isaacksz.
van Ruisdael (1628-1682) and Willem II van de Velde (1633-1707) from
the collection of the RMA were examined. A total of 27 paint cross-sections
was analysed using optical light microscopy, SEM-EDX and XRF analyses.
The resulting information about the used materials and techniques was
compared with the instructions given by Willem Beurs and this comparison
has shown many similarities. With this result, the current research joins the
58
previously demonstrated links between the instructions from De Groote
Waereld in ‘t Kleen Geschildert […] and the actual professional painting
practise in The Netherlands in the 17th century.
By means of this research, more insight has been gained on the value of
De Groote Waereld in ‘t Kleen Geschildert […] and the resulting thesis can
contribute to the annotated English version of the treatise, which is currently being undertaken by dr. A. Wallert (RMA). Although further research
is recommended, it may be concluded that the treatise of Willem Beurs
can be considered an uttermost interesting and possibly important contemporary source on the art of oil painting in the Northern Netherlands in the
17th century. ■
Acknowledgements
K. Keune (RCE), I. Verslype (RMA)
Restoration history of seventeenth
century cupboards from the Dutch
province Zeeland
■ MA thesis 2012 (in Dutch) ■ MA thesis supervisor S.M. Nijhuis (UvA)
■ MA thesis 2011 (in Dutch) ■ MA thesis supervisors A. Wallert (RMA, UvA), M.J.N. Stols-Witlox (UvA)
[Jorinde Koenen] This thesis concerns research on the value of De Groote
59
[Laura Koster] A study of the restoration history of five 17th century
cupboards from the Dutch province Zeeland has been carried out in order
to contribute to the history of furniture restoration, a field that has not been
studied extensively yet.
The Zeeland cupboard can be defined as a type of cupboard that probably
originates from the Dutch province of Zeeland, and is dated between 1620
and 1670. The oak cupboard has a separate under and upper section, and a
total height of about 160 cm. Typically, the cupboard is heavily decorated
with ebony and rosewood veneer, and carvings, e.g. lion heads, half-figures
and cherub heads. The doors are embellished with geometrical patterns of
cornice mouldings.
The many different structural elements, materials and decorations was
one reason to take this type of cupboard as a case study. A second reason
was that the cupboards are almost four centuries old, so likely to have
­undergone restorations.
The five Zeeland cupboards, all with an unknown conservation-restoration
history, have been visually analyzed and photographed in detail in order to
discover possible restorations. A systematic procedure has been set up to
document possible restorations, and instructions have been formulated how
to recognize them.
60
The characteristics of the cupboards, e.g. composition, the use of material
and decoration, as found in literature have been updated and expanded
with the results of this study.
At each cupboard various restorations were recognizable. For example,
parts such as the legs and the rear side of the cupboards have often been
replaced. Also, many small additions to the veneer, carvings and mouldings
have been discovered. Locks and pivot hinges have often been refastened
with screws, or have even been replaced completely. The study reveals that
at least one of the cupboards consists of old and new parts, and there is clear
evidence that the appearance of at least two of the other cupboards has been
modified in the course of time.
In addition to clearly recognizable alterations and restorations, also
potential alterations have been documented. This may be helpful in the
decision-making process of future restorations.
The results of this study not only provides us with insight into the
­history of restoration of these 17th century Zeeland cupboards but we also
have now a more substantial idea about how these cupboards originally
looked like, which should make it easier to recognize any restorations at
other Zeeland cupboards. ■
61
French owl hallmarks on the Horseman jewel, image made with the
Hirox KH-7700 digital microscope, courtesy of the Rijksmuseum Amsterdam
Acknowledgements
Kasteel Duivenvoorde (KD), A. de Vries (KD), Rijksdienst voor het Cultureel Erfgoed, S.E.M. Braat (RCE),
R.M. Kievits (RCE), E. Sadée (RCE), L. van Baars (IC), R. Klusener (HKA), J. Hoving (HKA), R. van Gilse
Authentic, fake, restored or pastiche?
Two Renaissance jewels from the Mannheimer
collection at the Rijksmuseum Amsterdam
■ MA thesis 2012 (in Dutch) ■ MA thesis supervisors
J.E. van Reekum (UvA), J. van Bennekom (RMA), E. van Bork
(RMA) ■ A paper about this work is in preparation
[Suzanne van Leeuwen] In 1952 part of the art collection of the
German banker Dr. Fritz Mannheimer (1890-1939) was added to the
­collection of the RMA. This collection includes many 16th and 17th
­century Renaissance jewels composed of gold, gemstones, pearls and
enamel. Recently, the period in which two of the RMA jewels were made
has been questioned.
In recent publications on Renaissance jewellery in other collections,
archival, literature and technical material research have been used to
make a statement on the authenticity of such jewellery. Since most of
the Mannheimer collection has never been subjected to this type of
­research, the aim of this thesis research was to answer the question
whether a provenance study, in combination with a non-destructive
60
technical evaluation, can provide data about the attribution of the two
RMA jewels. The technical research focused on the condition and the
manufacturing of the jewels, the determination of the gemstones and
the composition of the enamel. Data were acquired by means of visual
examination, using a dichroscope, a spectroscope and XRF.
The results suggest that provenance research can be very helpful in
determining the history of the jewellery and their current condition. This
information is valuable for the conservator-restorer when a treatment
plan has to be formulated. ■
Acknowledgements
D.J. Biemond (RMA), R. van Langh (RMA), J. Pedroso (RMA), J. van Iperen (RMA), T. Davidowitz,
H. Zwaan (NCB Naturalis Leiden), M. Akkerman, L. Opgenhaffen (LOPD, Grafische oplossingen
voor de Archeo­logie), W. Gans (Premsela en Hamburger, Amsterdam), A.A. de Tagle (RCE)
62
Acetylacetone – research on cleaning
brass elements on furniture
Etching bath with diluted nitric
acid and 925 silver coupon
covered with beeswax
elements on furniture can reveal difficulties concerning the desired
­appearance of the metal and the way to achieve this appearance. Common
products for cleaning brass generally require rinsing after treatment,
which is usually problematic in furniture conservation-restoration.
Therefore a cleaning product was sought that does not require rinsing.
It was expected that the chelating agent 2,4 pentanedione, also known
as acetylacetone, would be a suitable candidate because of its fast
­evaporation rate.
By reviewing the literature, a better knowledge of current conservation
practice regarding furniture with brass elements was obtained; it became
clear that in choosing brass as a decorative element on furniture, colour
has always played a large role. The similarity to gold of certain alloy
compositions, of around 30 wt % zinc, is and has always been much
­appreciated. In restoring brass on furniture conservator-restorers tend
to be reticent, which is not always because of the desire for reversibility
but also for mere esthetic reasons.
Three experiments were executed to obtain insight into the potential
role of acetylacetone in the conservation of brass. The first experiment
consisted of creating a chemical reaction by adding acetylacetone to five
different copper salts which are also present in corrosion products of
brass. FTIR analysis of the reaction products revealed that in all cases the
formation of a copper-acetylacetonate chelate was highly probable. The
objective of the second experiment was to attain understanding of the
long term consequences of treatment with acetylacetone. Brass test strips
underwent treatment of different durations, followed by different aftertreatments. Subsequently, the test strips were placed in an accelerated-­
aging machine under high relative humidity conditions (70%) and
with temperatures varying between 50 and 90 °C. The outcome of this
experiment was inconclusive, as treatment with acetylacetone left a layer
of some kind on all surfaces, regardless of the after-treatment. The precise
nature of these layers has not yet been established. A third experiment
was conducted in order to monitor the behavior of brass undergoing
extremely long exposure to acetylacetone. A test strip was therefore
submerged in the chelating agent for 30 days, after which the surface of
the brass strip appeared to have been etched by the chelation process. ■
Acknowledgements
M. Langeveld (IC), L. Megens (RCE), S. de Groot (RCE), K. Keune (RCE), B. Ankersmit (RCE),
I. Joosten (RCE)
62
Etching of silver; technology,
reconstruction and identification
■ MA thesis 2011 (in Dutch) ■ MA thesis supervisors T.C.P. Beentjes (UvA),
J. van Bennekom (RMA), S. Creange (RMA), I. Joosten (RCE) ■ Details of this research are
scheduled for publication in the Stavelij¹
■ MA thesis 2012 (in Dutch) ■ MA thesis supervisors J.E. van Reekum (UvA), N.H. Tennent (UvA),
J. van Bennekom (RMA), G. van Gerven (RMA)
[Julia Leunge] Conserving non-removable cast and sheet-metal brass
[Marije Meddeler] For optimal treatment of historical objects it is
e­ ssential to be able to identify manufacturing techniques. The aim of this
thesis was to develop a systematic ­approach to distinguish etching from
other decoration techniques on silver, based on visual characteristics and
the chemical composition of etched silver objects.
Etching experiments were conducted based on three historical written
sources (11th, 16th and 18th century) with silver etching recipes. Sterling
silver coupons were used to reconstruct these historic recipes. The coupons
were analyzed using stereomicroscopy, confocal microscopy, SEM
and SEM-EDS to identify the characteristics of the etching technique and
to enable differentiation between etching and other silver decoration
techniques.
Eight differentiation features were identified and used as a guide to
identify the decoration technique on works of art. Some objects in the
collection of the RMA were examined in order to test the systematic
­approach and its suitability in future research. ■
Acknowledgements
R. van Langh (RMA), A. Stijnman, J.P. van Rijen (Radboud Universiteit Nijmegen), J. Wolters,
H. van der Weijde, L. Megens (RCE), E. van Bork (RMA), A. Pappot (RMA),T. Davidowitz,
J. Nienhuis (RMA)
¹ Meddeler, M., Stavelij. 2013. Accepted for publication. http://www.stavelij/nl/ (04-03-2012).
65
Examination of crayonlines on a drawing by
Van Gogh with a Dino-Lite USB microscope
Oil, wax or grease? What kind of
coloured crayon did Vincent van Gogh
use in his drawings?
■ MA thesis 2011 (in Dutch) ■ MA thesis supervisors
B. van Velzen (UvA), B. Reissland (RCE), T. Meedendorp ( VGMA)
■ This abstract has been published previously¹
The Master-these has been published²
[Alexandra Nederlof] Vincent van Gogh drew during his stay in Antwerp
and Paris a number of drawings with colored crayons that probably
­contained an oil, wax or grease as binding medium. To gain new insight
into Van Gogh’s working method and to better understand the nature of
his drawing technique, this group of drawings has been closely examined.
Focus of this thesis were the questions: Which crayons were on the market
in late 19th century? What is the composition of the coloured crayons
used by van Gogh and can we trace back where he purchased them? Can
morphological characteristics reveal more about the nature of the binding
medium of a crayon?
¹ Nederlof, A., Journal of Paper Conservation 2011, vol. 12 – nr. 4, “Degree Works”.
² “Permanent, Water-Proof and Unequalled for Outdoor Sketching” Van Gogh’s use of wax crayons.
Reissland, Birgit, Alexandra Nederlof, Teio Meedendorp, Suzan de Groot, Henk van Keulen, Luc
Megens, Bas van Velzen. In: Van Gogh’s Studio Practice, Van Gogh Museum Publicaties, 2013.
64
In historical sources from the 19th and early 20th century fourteen
recipes were found for crayons containing diverse wax- or grease materials
as binding medium, always in combination. Most crayons were used for
writing on glass or metal, only a few were specifically meant for artists.
Also, no information was found on European manufacturers and suppliers
of such crayons, while more data were available on wax crayons on the
American market.
Four of the fourteen historic recipes found were reconstructed. The
influence of different ingredients on the quality of the crayon was studied,
as were their morphological characteristics. Eight drawings by Van Gogh,
and five by contemporary artists like Schuffenecker, Bernard and Gauguin
were examined visually in reflected, raking and transmitted light and under
magnification. XRF analysis was conducted at seven drawings. Fifteen
micro-samples were taken from selected drawings. These were analyzed
with FTIR and GC-MS.
XRF analysis confirmed the presence of pigments typically for the 19th
century. FTIR analysis revealed the presence of fillers (clay, chalk) in the
crayons but was less useful in determination of binding media. Better
results were obtained with GC-MS analysis, determining a combination
of beeswax and grease (tallow) in the three samples analyzed. This was in
agreement with the historic recipes. Based on examination of lines drawn
with reconstructed crayons and the original drawings, a nomenclature
for morphological features specific for crayons with wax,- grease- or oil
containing binding media was developed.
Crayons with beeswax and grease as binding medium were on the
market in the late 19th century and were indeed used by van Gogh as
drawing material. Visual examination proves to be an important predetermination step, but a final conclusion on which binding media are
present in a coloured crayon needs to be verified with GC-MS analysis.
The nomenclature for morphological features is usable to identify aged
and new crayon lines as crayon with a binding medium of wax and grease.
This thesis was part of the research project ‘Van Gogh’s studio practice in context’ which is a joint project of the VGMA, the RCE and Shell
­Research Laboratories. ■
Acknowledgements
Van Gogh Museum Amsterdam, Shell Research Laboratories Amsterdam, L. Megens (RCE), H. van
Keulen (RCE), S. de Groot (RCE), N. Lingbeek (IC)
66
Dry Cleaning: the effect of six
chemical residues on unvarnished
oil paintings
nished paintings with dry-cleaning materials, some chemical residues
can be left on the surface. These chemicals pose a potential risk to the oil
paint and therefore a study has been carried out, focusing on the optical
and mechanical effects that six extractable chemicals may have on
­unvarnished oil paint layers. Six chemicals were selected (a surfactant,
an UV-light stabilizer, two plasticizers, a vulcanizer and an antioxidant)
that have been detected recently on unvarnished paint surfaces (RCE,
unpublished results).
In the experiments the pure chemicals were applied at various
­concentrations on oil paint samples and microscope glasses. After lightaging, both accelerated-light and natural-light aging, the latter in line
with dark aging, color changes were evaluated visually, the naked eye in
daylight and UV light, and combined with colorimetric data. Cleaning
tests were carried out to establish whether the observed optical changes
could be remedied.
Discoloration connected to any of the six chemicals has not been observed, the main optical effect being an increase of the gloss after application of the substances to the oil paint samples. The Hirox 3D microscope
of the RMA allowed a detailed examination under 140 × magnification of
pressure tests on the oil paint samples. Oil paint samples treated with
the vulcanizer showed embrittlement. Vulcanizers are present in rubber
and some types of soft erasers and make-up sponges. The six types of
chemicals are all easily removable with aromatic solvents. ■
Acknowledgements
A.W. Brokerhof (RCE), M. de Keijzer (RCE), A.A. de Tagle (RCE), S. Jonker (trainee RCE),
K. Keune (RCE), F.J. Ligterink (RCE), L. Megens (RCE), H. Neevel (RCE), J. Pedroso (RMA),
B. Reissland (RCE), K.J. van den Berg (RCE), J. van Iperen (RMA), H. van Keulen (RCE), B. Wei (RCE),
F.R.E. Kuyvenhoven (RCE), B. Verissimo (RMA), M. Daudin-Schotte (RCE)
The execution of wax-resin linings by
Johannes Albertus Hesterman (1848 -1916)
and sons
A research into their working
method and materials
[Saskia van Oudheusden] This Master thesis concentrates on the wax-
resin lining method of the Dutch artist and conservator Johannes Albertus
Hesterman (1848-1916) and his sons Frederik Coenraad (1873-1932)
and Johannes Albertus Jr (1877-1955). Five 17th century portraits of
various doctors from the collection in the AM, which were lined by the
Hestermans in the years 1907-8 are investigated. In addition, reconstructions of wax-resin linings and research into literature and archival sources
have been carried out.
The similarities between the linings that have been studied suggest
a standardised lining method. The linings are carefully executed by the
Hestermans with attention to and respecting the original material. The
study of a logbook of the Hestermans has made clear that they lined
paintings as a preventative measure, with the exception of relatively new
paintings. This research shows that in their careful, and for that time,
ethical approach with regard to the lining of paintings, the lining method
of the Hestermans closely resembles that of Willem Antonij Hopman
(1828-1910) and his father Nicolaas Hopman (1794-1870), the founders
of the wax-resin lining method.
This research has been presented as a poster at the CiNC conferenceConservation in the Nineteenth Century, Copenhagen 13-05-2013 /1405-2013 as well as at the Interim Meeting of ICOM-CC Theory & History,
Copenhagen 16-05-2013 /17-05-2013. ■
Acknowledgements
M. van de Laar (Rma), K. Keune (RCE), N. Middelkoop (AM), G. Reichwein (AM), L. Visser (RKD),
M. Franken (RKD), M. te Marvelde (fhm), D.H. Johnson (Rice University, Houston, Texas USA),
C.R. Johnson (Cornell University, Ithaca, New York USA), R.G. Erdmann (University of Arizona,
Tucson, Arizona USA)
66
■ MA thesis 2012 (in Dutch) ■ MA thesis supervisor E.E. van Duijn (UvA)
■ A paper about this work is in preparation
■ MA thesis 2012 (in Dutch) ■ MA thesis supervisors: V. Blok (UvA) E.E. van Duijn (UvA),
E.M. Froment (UvA), O.V. van Maanen (UvA)
[Zuhura Oruç-Iddi] In the process of surface dirt removal from unvar-
67
68
[Martine Posthuma de Boer] In The Netherlands a considerable
amount of 18th century gilt leather hangings has been preserved ‘in situ’.
For the past decade heritage professionals have raised great concern about
their material condition, as several hangings locally show severe darkenings. These degradations have been registered in at least eight locations in
The Netherlands, but are expected to be more widespread. Conservatorrestorers and interior specialists suggest that the dark stains may be the
result of past conservation treatments with oil dressings and emulsions,
during the second half of the 20th century.
A systematic description and characterization of this darkening has
been started by examining two examples of Dutch 18th century gilt
leather hangings: Sint Pietershof, Hoorn and Weeshuis der Hervormden,
Schiedam. A literature and archive review of the products used in gilt
leather conservation during the past decades has been undertaken, allowing
a better understanding of the relationship between past conservation
treatments and the observed degradations.
Analyses of the different layers of the decorative ‘golden’ finish have
been carried out – consisting of a silver leaf applied with a parchment glue
and coated with an oil-resin varnish (‘golden varnish’). Visual observations
of the degradation phenomena have been complemented by comparing
cross-sections of un-darkened and darkened gilt leather samples, using
light microscopy, SEM-EDX and GC-MS. The results indicate that degradation processes related to the darkening are taking place in both the silver
and varnish layers.
This study is a first step in identifying the degradation phenomena
that occur in the decorative finishes of gilt leather hangings, which can be
related to past conservation treatments. The irreversible character of the
degradations in both silver and varnish layers, underlines the importance
of further identification of the degradation mechanisms and the role
of climatic conditions, such as relative humidity, moisture and gaseous
­pollutants. Eventually, this will contribute to the development of preventive conservation measures for gilt leather hangings ‘in situ’ that are
known to have undergone oil treatments in the past. ■
Acknowledgements
Rijksdienst voor het Cultureel Erfgoed (RCE), Rijksmuseum Amsterdam (RMA), Sint Pietershof
Hoorn, Vereniging Hendrick de Keyser (VHdK), M. de Keijzer (RCE), K.J. van den Berg (RCE),
H. van Keulen (RCE), F. Ligterink (RCE), M. van Bommel (RCE), L. Megens (RCE), J. van Iperen
(RMA), J. Pedroso (RMA), A.A. de Tagle (RCE), K. Vozza-van den Broucke (VHdK), N. van der
Woude (SRAL), E. Koldeweij (RCE), R. Scheres (IC), T. Sturge, P. Hallebeek
Darkening of gilt leather hangings,
Weeshuis der Hervormden, Schiedam
( Vereniging Hendrick de Keyser)
68
■ MA thesis 2012 (in Dutch) ■ MA thesis supervisors D. van Kempen (UvA), K. Keune (RCE), E. Nijhoff Asser (IC) ■ Prize for the
best MA thesis 2012 awarded by Migelien Gerritzen Fonds / Rijksmuseum Fonds ■ Publication of this work is in preparation
Darkening of gilt leather hangings
in The Netherlands
Characterizing degradation in the
decorative finish of two case-studies:
Sint Pietershof Hoorn and Weeshuis
der Hervormden Schiedam
69
70
The application of solvent gels
in the conservation of historic interiors
Two case studies
71
These case studies examine the considerations necessary before
selecting a cleaning gel and describe the customized solvent gel
specific to each artwork. The chemistry and function of the ingredients used to make these gels are explained. In this way, when a
conservator-restorer knows what is available, how to customize
it, and how the ingredients work in specific cases, a deliberated
cleaning system can be selected or devised. ■
developed alternative methods for the cleaning of painted surfaces.
His innovative approaches consist of utilizing specific aqueous
methods (enzymatic digestions, chelation, acid-base chemistry
and tailored solvent-surfactant systems) to aid in the removal
of non-original coatings or retouches. When thickened, these
water-based or solvent-based systems provide more control during
cleaning, in contrast to the application of free solvents. Also,
they are favorable for the removal of complex layers and can
solubilize a wide range of materials. Furthermore, these systems
can be formulated to unpack specific layers while leaving others
layers intact. Removing a specific layer requires some knowledge
about the paint composition of the object and the layer(s) to be
removed. Although Wolbers’ cleaning systems could resolve
problematic cases, they are not yet entirely integrated into
everyday practice in private and public conservation studios. His
philosophy that “a conservator should be able to make his own
cleaning agents and thus know what materials are being used,” is
an ambitious philosophy which requires chemical understanding
and insight.
Also, he does not want to provide ‘cure-all’ recipes, but rather
to offer a new methodology with which to manipulate and apply
various cleaning components.Two case studies have been carried
out involving the conservation treatment of a canvas mural
(ca. 3.3 m × 3.0 m) in the Holy Innocent Roman Catholic Church
in Brooklyn NY. This mural was damaged by water from a roof
leakage and darkened due to accumulated layers of dirt and soot
resulting from a fire in the past. A solvent based Carbopol-solventsurfactant system was tailored to remove the non-original alkyd
coating and the layers of dirt and soot from the water sensitive
emulsion paint. The second case study focused on the preliminary
investigation and proposal for treatment of a brick wall sculpture (ca. 3.0 m × 7.8 m) in Spencer Lab, Mechanical Engineering
­department of the University of Delaware in Newark. Due to
leaks in the roof and skylight areas over the years, ­efflorescence
and tide lines became visible at the surface of the mural. The efflorescence and coating were sampled and tested and subsequently a
Pemulen emulsion gel was tailored to remove the coating simultaneously with the efflorescence.
70
Acknowledgements
Stichting de Fundatie van de Vrijvrouwe van Renswoude, L. Megens (RCE), K. Keune (RCE),
M. de Keijzer (RCE), D. Hess Norris (WUDPAC), J. Hill Stoner (WUDPAC), S. Behrens (UD),
A. McCullin (UD), A. Cresci, T. Zadrozny, S. Zadrozny, C. Tomkiewicz, R. Fevola
The ideal state of the object:
four 17th century doors from the Hof
van Moerkerken in Mijnsheerenland
Application of a methodology
PD Res thesis 2012 (in Dutch) PD Res thesis supervisors N. van de Woude (SRAL),
K. Seymour (UvA, SRAL) ■ A paper about this work is in preparation
PD Res thesis 2012 (in English) PD Res thesis supervisors R. Wolbers (University of Delaware, USA),
K. Seymour (UvA, SRAL) ■ A publication about this work is in preparation
[Willianne van der Sar] In the 1980s, professor Richard Wolbers
[Merel van Schrojenstein Lantman] This thesis concerns the conser-
vation and restoration of a painted door from the 17th century. This
door is part of a group of four doors, painted at the same time for a
country house in the southwest of The Netherlands. These four doors
are very special, because doors from the 17th century, decorated with
colorful and beautifully painted life size figures, have very rarely
­survived in The Netherlands.
Today, the doors are still in the same house as they were made for, but
the interior of the house has undergone a lot of changes and the doors
too. This research started with a quest to find the original location of the
doors in the house. This was hoped to be achieved using architectural
paint research, archival research and research into the building history.
Traces of paint on the surface of the door that could be matched to traces
of paint on the doorposts or walls would prove their origin. These traces
were not found however. Research in archives and building history did
add a lot of information about the history of the house but not specifically about the doors.
The results of this research were applied in a pilot treatment of one
of the doors. What made this a challenge, was that the four doors have to
be treated as a group, and not as singular objects. Furthermore, a connection with the interior which they came from and will go back to must be
kept. Therefore, the method of stabilizing the object first and then look at
72
Oral history,
a source for the future
The application of oral history to
historic interiors and the history
of restoration in The Netherlands
during the 1970s
Door with image of a woman
with a feather; after treatment
Acknowledgements
H. Moerkerk, S. Moerkerk, M. Moerkerk, D. Stolk,
B. Olde Meierink (Bureau voor Bouwhistorie en Architec­
tuurgeschiedenis, Utrecht), E. Koldeweij (RCE), M. Polman
(RCE), B. van Os (RCE), M. Greil (Rgd), S. Nooren (Rgd),
H. Brouwer (Rgd), J. van Iperen (RMA), C.R. Matsen
(WMD), R. Wolbers (University of Delaware USA)
72
[Hinke M. Sigmond] Research has been carried out regarding
the working method of conservator-restorers of historic interiors
in The Netherlands during the 1970s. As research strategy a
qualitative research method, oral history, has been used in the
form of individual in-depth interviews.
The objective of the research was twofold. On one hand it
aimed at composing and adjusting a research method specifically
for this field, but which could be useful for other conservationrestoration professionals as well. On the other hand, with the
use of oral history, it was intended to gain more insight in the
history of conservation-restoration as a profession and, on a more
specific scale, information about working methods, the working
environment, and past restoration materials and techniques. More
knowledge about these subjects is valuable for future development
of the profession, and can be useful in daily practise, e.g. how to
deal with old restorations. Because of this broad approach, the
research had a strong inventory character.
A target group of thirteen conservator-restorers, active during
the 1970s in conservation-restoration of historic interiors, has
been approached, of which eight agreed to participate in the
research. The interviews have been recorded digitally and transcribed. An interview guide has been set up and used during the
interviews. Three themes played a prominent role in the guide:
background and education, working environment, and materials
and techniques. The interviews yielded a great deal of information,
not only in relation to the three subjects, but it has also revealed
new, interesting issues which were not foreseen. Insight has been
gained on conservation-restoration as a profession in the 1970s
and the mutual working relationship of conservator-restorers
with other colleagues in the field. Apart from the three foreseen
categories, new factors that played a role in gaining knowledge
in the working field have been established, namely the ‘Central
Laboratory’ and the ‘Rijksdienst voor de Monumentenzorg’
■ MA thesis 2011 (in Dutch) ■ MA thesis supervisors D. van Kempen (UvA), S. Stigter (UvA), B. Crijns (RCE)
■ Part of this work has been published in the magazine of the cultural heritage agency of The Netherlands (RCE) (2, 2013)
the aesthetics and determine where action
is needed, will not do in this case. An integral approach was needed to ensure a unified result. To achieve this, a methodology
was used to assess the different values
of the doors in order to make treatment
decisions. This methodology was adapted
from Barbara Applebaum as described
in her book “Conservation Treatment
Methodology”. To determine the ideal
state of the object, also the value model of
Alois Riegl as described in “The modern
cult of Monuments” was used.
The determination of the ideal state has
been tested in practice, by execution of a
treatment of one of the doors with the goal
of reaching the ideal state as previously
determined. During treatment, some problems were encountered and these made it
clear that not all treatment decisions can be
made before starting a treatment. Sometimes it is also necessary to deviate from
the predetermined goals.
Although the treatment was not yet
­finished by time of publishing this thesis,
the treatment has successfully met the
predetermined goals as a whole with a minimum of compromise. Application of the
method helped to make informed treatment
decisions and to achieve a unified result.
It is strongly recommended that the three
other doors will also be treated using the
same methodology. A paper about this
work is in preparation. ■
73
75
Research and restoration of
Family Portrait by Gillis van Tilborch
(appr. 1665)
PD Res thesis 2012 (in Dutch) PD Res thesis supervisors S. Meloni (MDH),
K. Seymour (UvA, SRAL) ■ Publication of this work is in preparation¹
In 1974 conservator-restorers remove a
later overpainting in St. Gerlachuschurch
Houthem to Limburg, so the baroque
frescoes are visible again.
Source: Cultural Heritage Agency of
The Netherlands
(Dutch Agency for Cultural Heritage). From the information
gained from the interviews, it can be concluded that the work
and learning experiences during practical work have played a
prominent role in the build-up of professional knowledge. The
career paths of those interviewed are diverse and are characterized
by a great deal of self-sufficiency. The interviews have also
given a more profound insight into developments in the field of
conservation-restoration and shifting values and interpretations
over time. In a broader sense the research has helped to position
the profession in its historic context. The research methodology
itself has proven to be successful and is, with some adjustments,
possibly useful for future research in this field. ■
Acknowledgements
R. Bremer, B. Jonker, P. Dijkman, H. Nagtegaal, P. de Ruyter, D. Schoonekamp,
A. Verheij, W. Haakma Wagenaar, T. Scholte (RCE), IJ. Hummelen (RCE), M. Eigenfeld
(Motivaction BV Amsterdam), J. Hill Stoner (WMD), E.E. van Duijn (UvA)
74
[Susan Smelt] As part of the two-year post-master
training course of the Conservation and Restoration
of Cultural Heritage at the UvA, an investigation and
restoration of the painting Family Portrait by the
Flemish artist Gillis van Tilborch has been carried out.
This painting, owned by the Royal Picture Gallery
MDH, was purchased in 1827 by King Willem I for the
Mauritshuis. Family Portrait is an oil painting on canvas
dating to the second half of the 17th century, it measures
approximately 80 × 104 cm and is signed in the lower right
corner “Tilborch”. The restoration of Family Portrait
was necessary to improve both the legibility and aesthetic
quality of the painting. Before the treatment, the painting
was covered with a thick layer of yellowed varnish with
a marked degree of cracking, as well as overpaint, both of
which were visually disturbing.
To support the decision-making process during the
restoration, an extensive literature and archival research
was carried out, focusing on the life and oeuvre of the
painter Gillis van Tilborch, his materials and techniques,
the provenance of the painting and the paintings restoration history.
Initially it was believed that the architect, Peter
­Balkenende, his family, including his son-in-law the
painter Paul Potter and Balkenende’s friends, the painters
Adriaan van Ostade, Carel de Moor as well as Gillis van
Tilborch himself were depicted in the painting. However,
in a 1874 catalogue the MDH revealed that this assumption
is incorrect. As a result, the identity of ­portrayed family is
currently unknown.
The painting is no longer on its original stretcher,
which was most likely replaced by W.A. Hopman during
a treatment in 1891. The original canvas is of plain weave
and made of linen; flax fibers that were spun into a thread.
Only along the top left cusping can still be seen. Tilborch
painted two priming layers on the painting, which were
¹ Mauritshuis Den Haag. In Focus, to be published.
76
Gillis van Tilborch, Family portrait, c. 1665, After treatment,
The Royal Picture Gallery Mauritshuis Den Haag
applied immediately and quickly in one or two coats of
paint. The floor of Family Portrait is remarkable; research
revealed the artist painted first a floor with tiles in checker­
board pattern in black and white and later covered it with
a brown paint to imitate a wooden floor. It is believed that
the artist intentionally let the tile pattern show through
the brown paint. In 17th century houses in Brussels it was
common to paint a checkerboard pattern on a wooden
floor. Tiles were not affordable for everybody.
The documented restoration history of the painting
starts in 1841. In this year, and again in 1845, the painting
was washed and varnished by the Amsterdam restorer
Nicholas Hopman. In 1888, William Antonij Hopman,
the son of Nicholas Hopman, varnished the painting. In
1891 the painting underwent two treatments: the first
by Alois Hauser, Berlin’s famous painting conservatorrestorer, who performed a small treatment and the second
in that same year by W.A. Hopman who gave the painting
a wax resin lining. Finally, in 1993 another small conservation treatment was performed. Obviously, the varnish
76
77
on the painting is most likely not original and consists of
several layers.
Prior to the restoration, the painting was extensively
documented in the forms of images and reports. Images
of the painting include both front and back, in normal
light, ­raking light and UV. Furthermore, the painting was
examined with the naked eye and under the stereomicroscope. In addition, a checklist was used to document the
condition of the painting for restoration. Structurally, the
wax resin lining had kept the painting in good condition,
although there were many aesthetic issues with the painting. After examining and documenting the condition of the
painting, a treatment proposal was written and accepted.
During the actual restoration, various types of
retouchings from previous restorations were found. It
became difficult to distinguish original paint from overpainted areas and therefore it was necessary to carry out
technical research.
Multiple imaging and analytical techniques were used,
including radiography of the painting overall, IRR imaging
of the painting overall and XRF to analyze the ­pigments
used by the artist. A number of cross-sections were taken,
embedded in resin, and examined under magnification,
and one was also analyzed using SEM-EDX. Lastly, a fiber
sample from the original canvas was analyzed using PLM.
Also, during the restoration cleaning tests were carried
out to determine the solubility of the varnish and eventually it was decided to use ethanol dispersed in Klucel G.
The characteristics of the various types of overpaint were
determined and they made a distinction from the original
paint possible.
At this moment the restoration of the painting is finished
and the painting is on show at the Prince Willem V Gallery
of the MDH. ■
Acknowledgements
P. Noble (MDH), C. Pottasch (MDH), A. van Loon (MDH), E. Buijsen (MDH),
Q. Buvelot (MDH), A. van Suchtelen (MDH), E. Gordenker (MDH), D. Anchin
(MDH), B. van Schoonhoven (MBvBR), S. van Sprang (Koninklijk Museum
voor Schone Kunsten, Brussel), A. Haack Christensen (Statens Museum for
Kunst, Kopenhagen), I. Groeneweg (UL), A. Fày (Szépmûvészeti Múzeum,
Boedapest), E. Koldeweij (RCE), H. Dubois (KIK-IRPA)
78
Decision making
on a Royal dressing table
A major restoration of an Italian
19th century dressing table of
ebonised wood with marble inlay
PD Res thesis 2012 (in Dutch)
PD Res thesis supervisors S.M. Nijhuis (UvA), C. de Smet (Paleis Het Loo)
[Saskia Smulders-de Jong] The restoration of an Italian 19th century dressing
table was carried out in the context of the completion of the post initial phase of
the UvA ­programme Conservation and Restoration of Cultural Heritage – Wood &
Furniture. This thesis forms the final conservation report of this process.
An ebonised and marble inlaid suite of furniture in neo-Florentine renaissance
style was purchased in 1874 by king Willem III (1817-1890). This set of furniture
became part of the collection of Paleis Het Loo (Apeldoorn, The Netherlands)
in 2004. One of the pieces is a dressing table. The construction, veneer, mouldings,
marble, mirror and finish of this dressing table were severely damaged. Many
damaged and loose parts had to be conserved or restored and missing parts
had to be complemented. Restoring the palatial character of the object was the
intention of this project so it can be displayed in the ­permanent exhibition in
the king’s bedroom.
Decision making is inseparable from the profession of conservation therefore
the decisions about the treatment of the dressing table ran as a leading thread
through this thesis. According to the results of various studies the best possible
restoration and reconstruction methods were selected. There was an interdisciplinary collaboration with art historians, scientists, marble specialists and fellow
conservator-restorers because of the diversity of existing materials in the object
and the nature of the studies.
The restoration, in cooperation with the furniture conservator-restorer of Paleis
Het Loo, was carried out in four months’ time. In addition to securing all the loose
parts, more than hundred missing parts were added, including 24 veneer fragments,
22 pieces of stone and 61 parts of moulding in seventeen different profiles with
a total length of twelve meters. Research was performed during this restoration
work. The applied marble was identified and historically accurate reconstructions
of the missing veneer, mouldings, stone and mirror were made. The manufacture
of the dressing table was almost completely revealed and the conjecture about the
authenticity of the black finish was strengthened on basis of scientific research.
The mutual influence of the choices related to the research and practical work
was great. The diversity of components and materials present in the dressing table
made a major contribution to this influence. Therefore, the decision making concerning this restoration project proved not to be ambiguous. ■
Acknowledgements
P. Rem (Paleis Het Loo), RCE, R. Klusener (HKA)
78
79
top Front view console table before restoration. The damage to the mouldings and the marble is clearly visible.
bottom Front view console table after restoration. All missing parts such as mouldings and marble have been complemented.
The console table, together with a mirror, forms the dressing table of the Dutch King Willem III, Het Loo Palace
(Dutch: Paleis Het Loo), inv. Number: RL8960-1
80
Royal & heavenly
Nineteenth century blue dyes in the
Rijksmuseum costume collection
analysed to establish if a correlation exists between the early synthetic
blue dyes used and the condition of the objects. This project was limited in
scope to objects created between 1857-1876, the period in which most early
­synthetic acid and basic dyes were discovered.
Samples were taken from six objects: three silken gowns, one woollen
gown, one doll with a silk dress and a batiste blouse with light blue ribbon.
In addition, samples were taken from three other objects for use as comparative material.
In this study, several analytical methods were employed. HPLC revealed
that several early synthetic dyes had been used, including Water Blue IN,
Fuchsine, Mauve, Indigo Carmine and Picric acid. However, six of the in
total eighteen samples contained a colorant undetectable by the HPLC.
Inorganic pigments like Prussian blue give no response when tested with
HPLC, so this was assumed to be a possible explanation. In order to conclu­
sively prove the presence of Prussian blue, a Prussian blue Indication Test
was performed, in addition to analysis with SEM-EDX and FTIR. All six
samples did indeed contain Prussian blue.
The costumes were further investigated, making use of a condition
­assessment form which was developed for this purpose. With the form, it
was possible to look systematically at and describe the damage of each of
the costumes. If any damage had occurred as a result of synthetic dye use,
fading, discoloration or bleeding of the dyes was expected to be found – but
surprisingly, all costumes were found to be in remarkably good condition.
To determine if storage conditions had favourably affected their state of
preservation, microfading was performed on two of the objects: one Prussian
blue dress, and the woollen dress with synthetic dyes. The Prussian blue
dress faded rapidly during light-fastness testing, and afterward the tested
area of 0.5 mm diameter had faded visibly, whereas the woollen dress seemed
imperceptibly affected by the fading test. However, a week later, the faded
spots on the Prussian blue silk dress had disappeared. This regeneration
behaviour of Prussian blue has previously been noted in paintings, and the
textile results imply that this behaviour also occurs in textiles dyed with
Prussian blue.
It seems remarkable and defying expectations that several of the samples,
dating from 1857-1876, were found to contain Prussian blue. Also the
observation that the costumes are in relatively good condition taking into
account their their 150 years of age, may possibly be due to the use of
­Prussian blue. Prussian blue is an inorganic compound and it has been
80
found to possess good wash-fastness properties. In several objects Water
Blue IN was found, often in addition to other synthetic dyes. Five different
dyes were found on the woollen dress, suggesting that the colour result is
more economically obtained by mixing dyes rather than having a dye for
every possible colour. Surprisingly, even dyes that normally require either
an acidic or an alkaline bath were found mixed on one object. One may
­conclude from this that neutral baths were used to bind these dyes to the
fibres. It would appear that synthetic dyes such as Picric acid and Indigo
carmine, and even natural dyes such as Cochineal, were still being used in
the late 19th century, even though alternative synthetic dyes with better
colourfastness characteristics were already on the market. ■
Acknowledgements
M. van Bommel (RCE), M. de Keijzer (RCE), H. Neevel (RCE)
Van Gogh’s cobalt blue
Research into the possible causes for trace
elements found by means of SEM-EDX in two
distinct variants of cobalt aluminate used by
Vincent Van Gogh 1886 -1890
■ MA thesis 2011 (in English) ■ MA thesis supervisors M.J.N. Stols-Witlox
(UvA), M. Geldof (RCE) ■ This research has been published by the Van Gogh Museum
Amsterdam as a part of a larger exhibition catalogue about the artist’s materials
and technique in 2013¹
■ MA thesis 2010 (in Dutch) ■ MA thesis supervisors R. Lugtigheid (UvA), B. van Velzen (UvA), S. Meijer (RMA)
[Joni Steinmann] Six 19th century costumes of the RMA collection were
81
[Lise Steyn] SEM-EDX analyses of dozens of cross-sections of Van Gogh’s
paintings revealed that he used two distinct variants of cobalt blue between
1886 and his death in 1890. Samples of his Parisian period (1886-1888)
contained a comparatively high Ni / Co ratio, whereas this ratio is much
lower in samples from his post-Parisian period (1888-1890). Also, Parisian
and post-Parisian samples showed differences in other trace elements.
Investigation of Van Gogh’s letters showed steady orders from Parisian
colour merchant Tasset et l’Hote (via his brother Theo in Paris) during
his post-Parisian period. Van Gogh’s paint orders were chronologically
tabulated and compared to SEM-EDX results for this research. It was possible to establish that the variant predominantly seen in the Parisian period
could be attributed to one colour merchant, Julien Tanguy, and the variant in the post-Parisian period to Tasset et l’Hote. Further comparison
of paint samples from other artists who had been known to use either of
these colour merchants have supported these findings.
¹ Steyn, Lise & Muriel Geldof. “Van Gogh’s cobalt blue” in Van Gogh Studio Practice. June 2013.
Jansen, Leo, Muriel Geldof, Ralph Haswell, Ella Hendriks, Sjaar van Heugten (eds.) Van Gogh
Museum Amsterdam: Mecatorfonds.
82
83
Chinese porcelain
and the art of bonding
A research on the darkening
of bonded fractures
Acknowledgements
Rijksdienst voor het Cultureel Erfgoed, Van Gogh Museum Amsterdam, Shell Nederland,
K. Mensch (Shell Technology Centre Amsterdam), E. Hendriks (VGMA), K. Pilz (VGMA), L. Megens
(RCE), M. de Keijzer (RCE), C. Pienaar (Harmony mine, South Africa)
[Marijke Top] Ceramics conservator-restorers sometimes experience
that after bonding freshly broken porcelain a darkening of the bond occurs. Naturally one wishes that bonds are not too visible, or at least not
disturbing. A cause for the darkening has not yet been determined. The
goal of this thesis was to gain more clarity about the possible cause(s)
of the darkening of bonded porcelain fractures, and to avoid it at future
restorations. The initial hypothesis was that darkening is caused by a
difference in refractive index of the adhesive (an epoxy resin) and the
porcelain glaze. For glass restoration it has already been determined that
a matching refractive index can lead to an (almost) invisible join.
To limit the amount of data, the research focused on Chinese porcelain.
Also, because the darkening seems to happen relatively often with this
type of porcelain. Tests have been performed to establish the composition
of Chinese porcelain bodies and glazes, because these aspects determine
the visual characteristics of the porcelain. Apart from that, several
­bonding tests have been performed on Chinese porcelain dating from the
17th to the 19th centuries. Objects on which a darkening appeared were
studied with a stereomicroscope and a scanning electron microscope.
Early on it could be determined that a mismatch in refractive index
(between adhesive and glaze) was not the cause of the darkening. Also
other hypo­theses, like migration of the adhesive into the body or under
the glaze, could be disproven, considering the very low porosity of the
porcelain body and the fusion of the body and the glaze.
An alternative explanation was found as the darkening of bonds seems
to be caused by a remaining amount of space between the two bonded
fragments. Sherds that seem to fit correctly, as judged by the naked eye,
can be slightly separated at the microscopic level. Research has shown
that when the space is 20 μm (or less) the fracture is nearly invisible, while
a space of 35 μm leads to a clearly visible darkening. The observation that
at the micro level porcelain fragments do not fit perfectly is probably
caused by a slight deformation of the porcelain on breaking. Adding a
white pigment to the epoxy resin can lead to a reduction of the visibility
of the fracture. Future research should reveal the optimal amount of
­pigment that is needed to make the bond less visible. ■
L. Steyn with Portrait
of Marchello Malpighi,
Amsterdam Museum
Acknowledgements
L. Megens (RCE)
82
■ MA thesis 2011 (in Dutch) ■ MA thesis supervisors K. van Lookeren Campagne (UvA),
N.H. Tennent (UvA), I. de Pree-Dommisse (UvA)
Because both cobalt blues show differences in traces of other elements,
19th century recipes and production processes of the pigment were
investigated, as well as the metallurgical processes to extract cobalt and
aluminium from ores. From the results it appeared that the nickel content
of the samples can be related to the different origins of the ores that were
used for the production of the pigments. ■
84
85
Restoration work on a commode
PD Res thesis 2012 (in Dutch)
[Tamara Sigrid Venema] During the two year postgraduate phase of
PD Res supervisors S.M. Nijhuis (UvA), J. Hoving (HKA), R. Klusener (HKA)
the Conservation and Restoration of Cultural Heritage programme at
the UvA, a project has been carried out concerning the conservation and
restoration of a commode that is owned by the furniture conservation
studio Hoving & Klusener. At the start of the project the commode was
in a poor state. The substrate and veneer were severely distorted, especially
on the left-hand side of the object. Also, poor fillings from previous
restorations were visible and the finish of the commode was covered with
dirt. Interestingly, this finish seemed to be an old and uniform layer. The
aged finish and discolored wood were considered to be patina, and it was
decided to preserve them. Obviously, this limited the options to treat the
veneer and substrate.
As the left-hand side of the commode was the most damaged, it was
decided to focus on the conservation of this side of the commode.
Before deciding about the treatment the finish was analyzed. Spot tests
used to identify the composition of the finish were not successful and also
optical techniques (UV light, microscopy) were inconclusive. The Hirox
3D microscope only showed the finish to be a compact film.
Subsequently, at the RCE several analytical techniques (e.g SEM-EDX)
were attempted but all the resins used to embed the samples, Polypol
(Polyservice PS 230) and Technovit (2000 LC), turned out to affect the
­finish on the sample. Also, a gold coating on the sample did not protect
the sample from the effect of the resin.
Eventually, pyrolysis GC-MS revealed that the finish consists of beeswax
and colophony (10:1) and a small amount of oil.
After the analysis of the finish, the animal glue, the veneer and
substrate were examined and their properties determined the possible
methods to treat the veneer on the left-hand side of the commode.
It was decided to lift the veneer, to remodel it partly and to adhere it
on the substrate.
Various options to lift the veneer safely were tested. The method that
was selected in the end was to lift the veneer with ethanol in blotting
paper and a spatula. The substrate was treated to increase the strength
of the construction. The veneer was flattened with moist and pressure.
After this the veneer was adhered on the substrate with a mix of bone and
hide glue (1:1).
At the end of the project, the conservation of the left-hand side of the
commode was finished. ■
Acknowledgements
J. van Iperen (RMA), K. Keune (RCE), M. de Keijzer (RCE), J. Pedroso (RMA), I. Joosten (RCE), J. van
der Sangen (IC), A. Wallert (RMA), H. van Keulen (RCE), G. Tauber (RMA)
Removing veneer with a spatula. The animal glue underneath the veneer is
crystallized with alcohol and absorbed in blotting paper. After a 3 to 4 minutes
the glue bond can be broken with a spatula
84
86
The investigation of the use of ion
chromatography for identification of
early stages of glass sickness
87
The Ince Blundell composite marble
statue o
f a man with an ivy wreath
‘Marcus Aurelius’: revisited / restored
Acknowledgements
M. van Bommel (RCE), A.N. Proaño Gaibor (RCE), L. Megens (RCE), I. Joosten (RCE), B. Lamain
(RMA), Museum Boijmans van Beuningen Rotterdam, F. Burghout (MBvBR), C. van Hees (MBvBR),
B. Schoonhoven (MBvBR), A.A. de Tagle (RCE), L. Gibson (University of Strathclyde Glasgow UK)
86
[Nicolas Verhulst] In the 18th century Henry Blundell
bought an antique over-life-sized statue of ‘Marcus
Aurelius’ to add to his collection at Ince Blundell Hall,
north of Liverpool. His private collection of antique
sculpture became the second largest in the United Kingdom, after the Townley collection (British Museum).
As a ‘composite’ sculpture, ‘Marcus Aurelius’ exemplifies
the tradition of 18th century restoration ethics. During
the condition report the sculpture was divided into three
different zones: the plinth with the feet were separated
from the main body and a third zone existed of 58 pieces.
The treatment proposal focused on a series of complex
issues. A range of pins and clamps needed to be removed
from lead and 18th century resin. After cleaning the
surface (removal of dirt), the disturbing staining of the
white Carrara marble by old resin needed to be tempered
or removed. Considering different cleaning methods, a
surface-acting impregnating gel worked by dissolving
4% agar in deionised water. Grey dirt layers and sulphation could be removed with a Nd:YAG laser. To reinstate
the structural integrity of the statue a ‘piston fit pin sleeve’
armature was devised, besides the use of common pins.
This enables an easier disassembly in the future, as the
stainless steel pins slide into stainless steel sleeves that are
fixed inside the holes with a bulked epoxy. For choosing
the correct colour of the filler seven adhesives with seven
fillers were tested. This ‘colourfill chart’ worked as a
­reference and each recipe could be adjusted by adding
more or less fillers when searching for the desired
¹ http://www.arch.columbia.edu/files/gsapp/imceshared/lld2117/StoneConf11-Wednesday-Poster-Presentations.pdf, pp. 205-206.
² Verhulst, N. and L. Barnden, “The Ince Blundel compostite marble statue
of a man with an ivy wreath – ‘Marcus Aurelius’: revisited /restored”, 12th
International Congress on the Deterioration and Conservation of Stone,
22 October – 26 October 2012 at Colombia University in New York, 2013,
to be published.
PD Res thesis 2012 (in English) PD Res supervisors L. Barnden (National Museums Liverpool UK),
M. Cooper (National Museums Liverpool UK), L. Biçaçi (UvA) ■ Details of this research has been published elsewhere¹
A full paper about this work has been accepted for publication²
■ MA thesis, 2012 (in English) ■ MA thesis supervisor N.H. Tennent (UvA)
■ A paper about this work is in preparation
[Guus Verhaar] Glass sickness is a form of glass degradation that is well
known in the world of glass conservation. The symptoms of the process
are sweating (or weeping) glass and crizzling. Much has been written
on the advanced stages of glass sickness and its conservation, but very
­little is known about the early stages. In particular, signs of the early
stages of glass sickness are difficult to pinpoint visually, as two recent
cases point out.
During an intensive monitoring of the glass collection of the RMA, it had
been observed that glasses in different stages in the deterioration process
and from different origins eventually showed similar degradation patterns.
Also, for some objects it was not clear whether they actually suffered
from glass sickness or if the surfaces were contaminated. At the same
time, independently, conservator-restorers at the MBvBR ­encountered
the same problems. Both museums developed a categorization of the
observed surface appearance, but often struggled to categorize objects
definitively, as degradation symptoms were not clear.
In order to get a better, clear-cut indication of the early stages of glass
sickness, the use of ion chromatography ( ion c.) has been investigated.
The cations that leach out of a glass are mostly sodium, potassium and
calcium ions and these ions fall precisely in the range of ions that can be
analyzed using ion c. at a parts per million detection level. Therefore,
ion c. is well suited to detect leached-out ions at glass surface deposits,
the initial, almost invisible, stage of glass sickness.
After setting up the ion c. system at the RCE laboratories, sampling
and extraction experiments were carried out that eventually led to an
extraction protocol that yields reproducible results.
Furthermore, a few surface samples have been taken from museum
objects and analyzed, demonstrating the potential of this technique.
Complementary results from XRF and SEM-EDX analyses showed that
degradation products can be linked to the composition of a glass. ■
88
89
The originality of a transparent
coating on a cabinet from the Jachthuis
Sint Hubertus
Marcus Aurelius (Ince 569)
National Museums Liverpool (left),
Nicolas Verhulst, 2012 (right)
■ MA thesis 2012 (in Dutch) ■ MA thesis supervisors S.M. Nijhuis (UvA), P. van Duin (RMA)
■ Details of this research will be published elsewhere
properties. Eventually, after applying two coatings of a
10% Paraloid B72 in acetone barrier layer, the ‘colourfill’,
based on ‘HXTAL NYL-1’ epoxy, ‘Fumed Silica’ and alabaster
powder was applied. Finally a protective coating of
­microcrystalline wax was applied to protect the surface
from surface dirt ingression in the future. ■
Acknowledgements
A La Pensée (National Museums Liverpool UK, NML), B. Sillitoe (NML),
D. Whitty (NML), G. Musket (NML), D. Carty (IC), J. Podany ( J. Paul
Getty Museum Los Angeles USA), Norman Weiss Education Fund Student
Scholarship, The Netherland-America Foundation, B. Wei (RCE)
[Boudewien Westra] Furniture that are presented for conservation-
restoration nowadays seldom have their original coating. As a result,
a lot of furniture has lost its original appearance. Knowledge of original
coatings helps to determine the original appearance of these objects and
can also have an impact on future restorations.
Research of transparent coatings of Dutch furniture made between
1600-1940 is a tripartite project of the RMA, the RCE and the UvA. Within
this project, a study has been carried out of transparent coatings on
­furniture in the Jachthuis Sint Hubertus, located in the ‘Nationale Park
de Hoge Veluwe’ ( The Netherlands). The Jachthuis, where the KröllerMüller family lived, was built between 1916 and 1920. It was modeled
after the work of the architect H.P. Berlage (1856-1934) and can be
described as ‘Gesamtkunstwerk’. One of the pieces of furniture in the
living-room, a cabinet of teak and ­coromandel that has been made by the
prominent company H.P. Mutters & Zoon between 1920-1924, has been
analyzed in detail.
Visual analyses (UV, day-light) revealed a smoothly applied coating,
which advocates a possible original coating. GC-MS analysis revealed a
surprizing composition of the ­coating, consisting of linseed oil, shellac
and colophony. This led to an analysis of sources from the beginning
of the 20th century containing information on and recipes of varnishes.
Finally, the coating of the cabinet has been put into a broader context
by technical research done on the coating of two comparable pieces of
­furniture. Both were finished in the same way as the cabinet.
Based on the research that has been carried out, it was concluded that
the coating of the cabinet in the living-room of the Jachthuis is original. ■
Acknowledgements
H. van Keulen (RCE), R. Kievits (RCE), Kröller-Müller Museum (KMM), S. Glerum, J. Pedroso (RMA),
B. Mühren (KMM), M. van der Sande (KMM), I. Breebaart (RMA), J. van Scherpenzeel
H.P. Berlage / H.P. Mutters & Zoon, Cabinet,
Jachthuis Sint Hubertus,1900 -1924, 178,5 ×199 × 44 cm
88
90
Transformator transforms
Guiding changes in an artwork by
Thomas Hirschhorn
Thomas Hirschhorn,
Transformator, 1997.
3,5 × 3,5 ×1,5 m
PD Res thesis 2012 (in Dutch) PD Res supervisors L. Beerkens (SRAL), M. Verboven (Stedelijk Museum
voor Actuele Kunst, S.M.A.K., Ghent, Belgium)
[Karolien Withofs] An internship in the conservation studio at the S.M.A.K.,
Ghent, Belgium, was part of the two year postgraduate phase of the education
programme for conservation and restoration at the UvA. The internship consisted of the conservation-restoration of the artwork Transformator (1997),
made by the Swiss artist Thomas Hirschorn.
The artwork is made of used objects and industrially produced, nondurable materials. It consists of four piled tables covered with blue garbage
bags, which are fixed with brown packaging tape. On each table lies a big
rock made of aluminium foil and a drawing or a collage. On the upper table
a video shows the written text Etre en haut c’est etre en haut with no sound.
Next to the tables four big teardrops hang on the wall. They are made of
aluminium foil, painted in red and blue. All components of the artwork are
interconnected with strings of squeezed aluminium foil.
In the first years of its existence Transformator has been exhibited frequently until its condition deteriorated resulting in no further exhibitions.
The artwork remained in the depot of S.M.A.K. for ten years. During this
postgraduate project the material condition of Transformator and its components was mapped. The aluminium foil has suffered mechanical damage
which translates in damages in the paint layer on top of it. The paint itself is
brittle and could not follow the movements of the aluminium foil, resulting
in loose paint and paint loss. The teardrops were so fragile, they could not
be hung on the wall anymore. The garbage bags had tears and scratches and
the degraded packaging tape could not fix the bags to the tables anymore.
As a result, the bags hung loosely around the table tops.
The implications of this condition for the meaning of the artwork, as
well as Hirschhorns views on the conservation and the lifetime of his
works have been considered and a conservation strategy has been defined.
­Components that have been industrially produced and not modified by
the artist, like the packaging tape, can be replaced by new material if they
are degraded badly. Letting the degraded material be part of the artwork
contradicts the meaning of the material in the work, as a universally known
and ever available material.
Components that have been created by the artist are irreplaceable. For
these components a conservation treatment has been defined. A supporting
hanging system for the tears has been developed. The paint on aluminium
foil has been consolidated and lacunae have been retouched. Consolidation
and retouching of the paint on the PP packaging tape has been done as well.
However, future adhesion problems are to be expected because the apolar
PP surface is not appropriate for good adhesion. When that time comes, the
90
added materials will be removable. The plasma pen, still in development at
the University of Bern, will hopefully be available as a tool for conservators
to give this adhesion problem an appropriate and durable solution.
Transformator will benefit greatly from a good storage system. The
components should be protected from damaging mechanical forces and
from light which is the main cause of chemical degradation of these
­materials. The long-term preservation of the video-component poses some
questions still, mainly because CRT monitors will become obsolete. The
exhibition of the artwork, programmed in the near future, is a good cause
for contacting the artist and establishing a long-term preservation plan for
the video-component. ■
Acknowledgements
Stedelijk Museum voor Actuele Kunst (S.M.A.K., Ghent, Belgium), S. Saverwyns (KIK-IRPA),
W. Fremout (KIK-IRPA)
92
93
Looking for Colijn de Coter:
technique, decay or restoration?
PD Res thesis 2012 (in Dutch) PD Res supervisors K. Seymour (UvA, SRAL), G. Tauber (RMA),
W. de Ridder (RMA) ■ A paper about this work is in preparation
[Nienke Woltman] In this thesis the treatment and research of The
Lamentation of Christ are reported. The painting is attributed to Colijn
de Coter and dated between 1510 and 1515. It belongs to the collection of
the RMA since 1875. The painting will be exhibited in the newly renovated
RMA. In preparation of this, restoration of the painting was carried out.
The title of this thesis addresses the premise and at the same time the
ethical guideline of the conservation-restoration. The goal of this restoration was to bring the painting back as close as possible to its original state.
To discover the original appearance of the painting research was carried
out. The underlying origin of several phenomena found during restoration
was investigated. Hereby the following classification was made: are the
found phenomena caused by something that is inherent to the technique
of the artist, by the deterioration of the materials or by a later restoration?
It is important to make a distinction between these causes, because this
influences the choice of treatment.
Art historical information about the artist and the painting have been
documented, with attention to the oeuvre of de Coter and the position
of The Lamentation in this oeuvre. Little is known of Colijn de Coter,
and only three signed paintings of him are known. The Lamentation is
not signed but is generally accepted as a painting by the master. In the
archives of the RKD information was found about an existing other version
of this painting, owned by a private collector. The whereabouts of this
painting was traced and it was brought to the studio, where it was
­subjected to a thorough investigation. If further research of this painting
proves that it was made around the same time and in the same studio,
much new information about the studio practice of Colijn de Coter can
be gleaned.
The buildup of the different layers and the properties of the original
materials have been addressed in order to find out how the artist actually
made the painting. Knowledge of the used ­materials helps in assessing the
condition of the painting and thereby influences the choice of treatment.
On the basis of SEM-EDX and XRF analyses on The Lamentation several
characteristics were established that may have been common practice in
the studio of de Coter.
The overall condition of the painting is fair. The varnish has ­yellowed
and in several areas previously applied discolored overpaint was found.
Underneath these over-painted areas, old filling material and damaged
original paint were discovered. During a previous restoration the painting
has probably been over-cleaned, and as a result the paint is abraded.
92
Colijn de Coter.
The Lamentation of Christ.
After restoration. Daylight
Two phenomena were investigated in depth. Firstly, SEM-EDX and XRFanalyses were carried out to investigate several small holes in the yellow
and orange paint layers of the headdress of Mary Magdalene. Secondly,
UV fluorescence has revealed the presence of a layer in several areas.
From a GC-MS analysis it could be concluded that this layer was probably
­applied in a previous restoration. As the layer is hardly visible in daylight,
and could not be removed without damaging the original paint, it was
­decided to leave it untouched.
The results of technical analyses and research of the other existing
version of The Lamentation helped to determine the original appearance
of the RMA painting. The distinction between technique, decay and
restoration proved to be useful in the quest of Colijn de Coter and helped
in determining the choice of treatment. Furthermore for the treatment
of the RMA painting, the panel from Leersum proved to be of great help
as well. ■
Acknowledgements
Rijksmuseum Amsterdam, M. Ubl (RMA), A. Wallert (RMA), J. van Iperen (RMA), K. Keune (RCE),
M. Leeflang (Museum Catharijnen Convent Utrecht), S. Laemers (RKD), mr. Stratenus, G. van Gerven
(RMA), C. van Wijk (RMA), B. Stabik (SRAL), J. van Och (SRAL), I. van Rooy (Bonnefanten Museum
Maastricht; BMM), C. Zijlstra (BMM), L. Hendrikman (BMM), M. Zeldenrust (RMA), H. van Keulen
(RCE), A. Vandivere (UvA, RMA)
94
Alphabetical list of organizations
and companies which are mentioned
in the abstracts
Alphabetical list of abbreviations of
organizations and companies which are
mentioned in the abstracts
■ Amsterdam Museum ( AM )
■ Artemis UK
■ Paleis Het Loo
■ Premsela en Hamburger Amsterdam
■B
lue Tortoise Conservation London UK ( BTC )
■ Bonnefanten Museum Maastricht
■B
ureau voor Bouwhistorie en Architectuur­
geschiedenis Utrecht
■ Bijzondere Collecties UvA ( BC )
■ Brenntag Nederland / Lumilux
■ Radboud Universiteit Nijmegen
■ Restauratie Atelier Amsterdam ( RAA )
■ Rice University, Houston, Texas USA
■ Rijksdienst voor het Cultureel Erfgoed
( RCE, formerly ICN )
■ Rijksgebouwendienst Den Haag ( Rgd )
■ Rijksbureau voor Kunsthistorische Documentatie
Den Haag ( RKD )
■ Rijksmuseum Amsterdam ( RMA )
■ Rijksmuseum Twenthe ( RMT )
■ CICRP Marseille
■ Cornell University, Ithaca, New York USA
■ Fablab Amsterdam
■ Fablab Maastricht
■ Flentrop Orgelbouw
■ Frans Hals Museum ( FHM )
■ Harmony mine South Africa
■ Hout- en Meubileringscollege Amsterdam
■H
oving & Klusener V.O.F Amsterdam ( HKA )
■ Instituut Collectie Nederland ( ICN, nowadays: RCE )
■ J. Paul Getty Museum Los Angeles USA
■ Kasteel Duivenvoorde
■ Koninklijke Bibliotheek Den Haag
■K
oninklijk Instituut voor het Kunst­patrimonium
Brussels ( KIK- IRPA )
■K
oninklijk Museum voor Schone Kunsten Brussel
■ Kröller-Müller Museum Otterlo
■ Kunsthistorisches Museum Wien Austria
■ School of Conservation Copenhagen Denmark
■ Shell Nederland
■ Shell Research Laboratories Amsterdam
■ Shell Technology Centre Amsterdam
■ Sint Pietershof Hoorn
■ Stadsarchief Amsterdam
■ Statens Museum for Kunst Copenhagen Denmark
■ Stedelijk Museum Amsterdam ( SMA )
■ Stedelijk Museum Schiedam
■ Stedelijk Museum voor Actuele Kunst ( S.M.A.K.)
Ghent Belgium
■ Stichting de Fundatie van de Vrijvrouwe van
Renswoude
■ Stichting Restauratie Atelier Limburg ( SRAL )
■ Stichting Westerkerk Enkhuizen
■ Struisvogelboerderij Monnikenwerve Sluis
■ Szépmûvészeti Múzeum Boedapest Hungary
■ Teylers Museum Haarlem
■ The Netherland-America Foundation
■ L OPD, Grafische oplossingen voor de Archeologie
■M
agister Varnish Products Hollandse Rading ( MVP )
■ Mauritshuis Den Haag ( MDH )
■ Monumentenzorg Hoorn
■ Motivaction BV Amsterdam
■M
useum Boijmans van Beuningen Rotterdam
( MBvBR )
■ Museum Catharijnen Convent Utrecht
■ Museum Rotterdam
■ Museum van Loon Amsterdam
■ National Museums Liverpool UK
■ NCB Naturalis Leiden
■ Nemoto Europe BV
■N
orman Weiss Education Fund Student Scholarship
95
■ Universitaire Bibliotheken Leiden
■ Universiteit Leiden ( UL )
■ Universiteit Twente ( UT )
■ University of Arizona, Tucson, Arizona USA
■ University of Delaware USA
■ University of Strathclyde Glasgow UK
■ Universiteit van Amsterdam ( UvA )
■ Van Gogh Museum Amsterdam ( VGMA )
■ Vereniging Hendrick de Keyser
AM
BC
BTC
FHM
HKA
ICN
KIK- IRPA
MBvBR
MDH
MVP
RAA
RCE
Rgd
RKD
RMA
RMT
SMA
SRAL
UL
UT
UvA
VGMA
WMD
Amsterdam Museum
Bijzondere Collecties UvA
Blue Tortoise Conservation London UK
Frans Hals Museum
Hoving & Klusener V.O.F Amsterdam
Instituut Collectie Nederland (nowadays: RCE )
Koninklijk Instituut voor het Kunstpatrimonium Brussels
Museum Boijmans van Beuningen Rotterdam
Mauritshuis Den Haag
Magister Varnish Products Hollandse Rading
Restauratie Atelier Amsterdam
Rijksdienst voor het Cultureel Erfgoed (formerly ICN )
Rijksgebouwendienst Den Haag
Rijksbureau voor Kunsthistorische Documentatie Den Haag
Rijksmuseum Amsterdam
Rijksmuseum Twenthe
Stedelijk Museum Amsterdam
Stichting Restauratie Atelier Limburg
Universiteit Leiden
Universiteit Twente
Universiteit van Amsterdam
Van Gogh Museum Amsterdam
Winterthur Museum, Winterthur, Delaware USA
Abbreviations of analytical techniques
FTIR
HPLC
IRR
GC-MS
PLM
SEM
SEM-EDS
SEM-EDX
UV
XRF
Fourier -Transform Infrared Spectroscopy
High Performance Liquid Chromatography
Infrared Reflectography
Gas Chromatography-Mass Spectrometry
Polarized Light Microscopy
Scanning Electron Microscopy
Scanning Electron Microscopy with energy dispersive X-ray spectroscopy
Scanning Electron Microscopy with energy dispersive X-ray spectroscopy
Ultraviolet
X-ray Fluorescence
Other abbreviations
■ Whitechapel Bell Foundry London UK
■ Winterthur Museum, Winterthur, Delaware USA
( WMD)
94
IC
C&R
rio
PI
ICOM
Independent conservator-restorer
Conservation and restoration of cultural heritage
restaurator in opleiding (conservator-restorer in training)
Post-Initial (= post-master part of the programme at the UvA)
International Council of Museums
96
Team C&R
96
97
Professors, lecturers
and management
98
Professors
1 Research
2 Publications
3 Other activities
99
Prof. dr. Norman Tennent
Prof. dr. Jørgen Wadum
Professor of conservation science
n.h.tennent@uva.nl
Professor in conservation and restoration;
chair of the section
j.wadum@uva.nl
1 Glass crizzling. Natural and accelerated
aging of epoxy resins.
Laser ablation-inductively coupled plasmamass spectrometry.
Computer match pigment selection for
retouching zinc hydroxychloride mortar.
2 “Multi-element quantification of
ancient / historic glass using laser ablationinductively coupled plasma /mass spectro­
metry using sum normalization calibration”, Elteren, Johannes T. van, Norman
H. Tennent and Vid S. Šelih, Analytica
Chimica Acta 644 (2009) pp. 1-9.
“Polymer conservation treatments for
stained glass in the Burrell Collection,
Glasgow: an assessment of 25 years of
natural aging”, Tennent, Norman H.,
In: ICOM-CC 16th Triennial Conference
Lisbon 19-23 September 2011: preprints
[cd-rom]. Bridgland, Janet (Editor).
ICOM Committee for Conservation
(Corporate Author). Critério-Produção
Grafica, Lda. (2011).
3 Member of UK Heritage Science
Advisory Panel.
Visiting Honorary Professor, University
of Glasgow.
1 The recording and dating of 17th
c­ entury marks on Flemish and Dutch
panel marks.
An investigation into painting techniques
seen in the context of ageing and conservation treatment with an emphasis on
the long term effect of the keeping of the
objects seen in relationship to current and
future reception. An interdisciplinary
research between conservator-restorers,
conservation scientist and curators.
2 Wadum, J., N. Streeton, “History and
use of panels or other rigid supports for
easel paintings”, in Stoner J.H. & R.A.
Rushfield (eds.): Conservation of Easel
Paintings – Routledge Series in Conservation and Museology (2012) pp. 49-114.
Wadum, J., M. Scharff, “Tracing the indivi­
dual ‘handwriting’ of four 16th century
artists through their underdrawings”,
in Hermens, E. (ed.): On the Trail of Bosch
and Bruegel – Four Paintings United
under Cross-examination. CATS Series of
Technical Studies. Archetype Publications
in collaboration with CATS / SMK (2012)
pp. 59-77.
98
3 Director of CATS – Centre for Art
Technological Studies and Conservation,
Copenhagen, a collaborative research venture between Statens Museum for Kunst
(SMK), the National Museum of Denmark
(NMD) and the School of Conservation
(SoC) at the Royal Danish Academy of
Fine Arts, Schools of Architecture, Design
and Conservation.
Co-chair of the Advisory Group to
The Getty Panel Paintings Initiative,
Los Angeles, USA.
100
Lecturers
101
Book and paper
Elizabet Nijhoff Asser
Jos Schrijen
Bas van Velzen
e.nijhoffasser@uva.nl
j.j.j.schrijen@uva.nl
s.t.j.vanvelzen@uva.nl
1 Research in 19th century anatomical
1 Making an English-language thesaurus
1 PhD-research (ongoing): ‘Rendement
models of paper-mâché made by Docteur
Auzoux.
2 Watteeuw, L, E. Nijhoff Asser, L.
Tubeeckx, S. Hulpiau, E. Gabriëls: “Stof
tot nadenken”, condition survey of the
bookcollection of the Library of the
­University of Ghent, 2009.
Nijhoff Asser, E., & B. Reissland, e.a. :
“Lost fingers, scurfy skin and corroding
veins – conservation of anatomical papiermâché models by Dr Auzoux”, 15th
Triennial Conference of ICOM-CC, New
Delhi, Preprints Vol. 1, 2008, pp. 285-292.
3 RNA (Restoration Nijhoff Asser),
conservator-restorer of paper, parchment
and leather.
Vice-chair of the Belgium-Netherlands
Society of Bookbindings.
for describing bindings. This project is led
by N. Pickwoad, Ligatus Research Centre,
CCW Graduate School, University of the
Arts, London.
2 Lem C. en J. Schrijen: “Het gebruik van
zeemleren beschermruggen op boeken met
houten platkernen in de Maurits Sabbe­
bibliotheek in Leuven”, in: Knapen L. en
L. Kenis (ed.): Hout in boeken, houten
boeken en de fraaie konst van houtdraayen.
Uitgeverij Peeters, 2008.
par bac’; developing a simple procedure
for the analysis of paper.
2 Co-author of Schalkx, Hilde et al.
“Aqueous treatment of water-sensitive
paper objects”. Journal of Paper Conser­
vation, vol. 12, nº 1 (2011): pp. 11-20.
3 Author and /or editor of “Instructables”
4 × per year in IADA Journal of Paper
­Conservation.
100
102
Lecturers
103
Contemporary art
Ellen Jansen ( MA | PD Res )
Evelyne Snijders
Drs. Sanneke Stigter
e.m.jansen@uva.nl
e.snijders@uva.nl
s.stigter@uva.nl
1 Research into the properties and
2 “The treatment of a polyurethane rigid
1 PhD-research (ongoing): Between
degradation processes of phosphorescent
pigments.
Research into the possibility of retouching
gaps in phosphorescent paint.
2 Jansen, Ellen: “Survival of the Survival
Series. Conserveringsstrategieën voor
een lichtkrant met een intern geheugen”,
Simulacrum, jaargang 20, nr. 2, mei 2012.
Extensive case description of Selections
from the Survival Series (1983) by Jenny
Holzer (Kröller-Müller Museum, Otterlo)
in the framework of the Obsolete Equipment project for the site of Dutch Media
Art Institute (no link available).
3 Independent conservator-restorer
of Contemporary Art.
Teacher and Coordinator workshop
Conservation and Restoration of New
Media for the training Preservation and
Presentation of the Moving Image (UvA
Master’s program, January 2013).
foam floor piece by Ger van Elk: a study
in the conservation of plastics” In: ICOM-CC
16th Triennial Conference Lisbon 19-23
September 2011: preprints [cd-rom].
Bridgland, Janet (Editor). ICOM Committee for Conservation (Corporate Author).
Critério-Produção Grafica, Lda. (2011).
3 Independent conservator-restorer of
contemporary art.
Concept and Material: The conservator’s
role in photograph based and conceptual
works of art: Ger van Elk, Joseph Kosuth,
Jan Dibbets, as part of the interdisciplinary
NWO funded research program New
Strategies in the Conservation of Contemporary Art initiated by Maastricht
University and RCE.
Member of NeCCAR, Network for the
Conservation of Contemporary Art
Research, a three year NWO-funded international research network.
2 Beerkens, L., P. ‘t Hoen, IJ. Hummelen,
V. van Saaze, T. Scholte & S. Stigter (Eds.),
“The artist interview: for conservation
and presentation of contemporary art:
guidelines and practice,” Heijningen:
JAP SAM Books 2012.
Stigter, S., “How material is conceptual
art? From certificate to materialization:
installation practices of Joseph Kosuth’s
Glass (one and three)’’, in: Scholte, T. &
G. Wharton (Eds.), Inside installations:
theory and practice in the care of complex
artworks, Amsterdam: Amsterdam
­University Press, 2011, pp. 69-80.
3 SBMK steering committee member – Foundation for the Conservation of
Contemporary Art.
Founding member of INCCA Education.
102
104
Lecturers
105
Glass, ceramics and stone
Lisya Biçaçi
Daan Blits
Kate van Lookeren Campagne BA
l.bicaci@uva.nl
d.m.blits@uva.nl
k.e.vanlookerencampagne@uva.nl
1 Research (ongoing): Glass appliqué a
1 Research to tile tableau of housing
1 PhD-reserach (ongoing): The techno­
multifaceted challenge. Conservation and
restoration of architectural glass from the
post-war period to the present.
3 Symposium ‘Care and Conservation of
outdoor sculptures’ Castles Amerongen
and Heeswijk in collaboration with
Artesis and the UvA on March 21, 2013.
Coordinator ‘Itinerant Course on Stone
Conservation (III)’– (3/31/2013 - 7/6/2013).
­corporation De Key, Amsterdam Museum.
3 Independent conservator-restorer and
guide in museums.
logy of Dutch tin glazed tiles produced
between 1580 and 1800 and its influence
on glaze deterioration.
2 “17th century Dutch Tiles in the
Tropics: the importance of state and trait
on deterioration processes” ICOM-CC
triennial meeting ceramic and glass group,
SPA uitgevers, Amsterdam, 2013 (in press).
“A Comparative View of Academic
Training Programmes in Ceramic and
Glass Conservation”, ICOM-CC, triennial
meeting ceramic and glass group, Grafika
Soca, Nova Gorica, Slovenia 2007.
3 Coordinator local organizing-committee ICOM-CC C&G working group, triennial
conference Amsterdam 2013.
Assistant coordinator ICOM-CC Ceramic
and Glass Working Group (education).
Consulent Collectiewacht Gelderland.
Restauratieatelier van Lookeren Campagne.
104
106
Lecturers
107
Lecturers
Historic interiors
Metal
Drs. Daniëlle van Kempen
Dr. ir. Mariël Polman
Tonny Beentjes
Janine van Reekum MA
d.vankempen@uva.nl
m.g.polman@uva.nl
t.p.c.beentjes@uva.nl
j.e.vanreekum@uva.nl
1 Research to 19th and 20th century
1 Van Doesburg-Rinsemahuis Drachten
1 PhD-research (ongoing): Rodin’s
1 The history and appearance of metal
decorated leather.
2 Kempen, D. van, “Materiaal met een
rijk verleden; restauratie van goudleer”.
Cr. 3 (2006), pp. 19-22.
Kempen, D. van, E. Koldeweij. “Dilemmas
and solutions on the conservation treatments of three gilt leather rooms in The
Netherlands”. ICOM-CC; 14th Triennial
Meeting The Hague 12-16 September
2005, pp. 263-270.
2 Nelissen, S. and M. Polman (2012):
“Duikers’ Open Air School: Re-Use or
Contin-Use” Docomomo International,
Global Design. Journal 47, 2012/2. Barcelona, 2012, pp. 34-42.
Polman, M. and M. de Keijzer (2010)
“Duiker’s colours “ in: Sanatorium Zonne­
straal, history and restoration of a modern
movement. Meurs, Paul, Marie-Thérèse
van Thoor (eds.) NAi Publishers. Rotterdam, Zonnestraal estate bv, (R)MIT Faculty
of Architecture TU Delft, pp. 201-205.
3 Specialist architectural paint research
Cultural Heritage Agency of The Netherlands.
“The Thinker”: the development and
implementation of new conservation
strategies and the investigation of bronze
casting technology.
2 “An innovative treatment of a severely
damaged bronze, the Thinker by Rodin”,
Lasers in the Conservation of Artworks
(LACONA IX), Saunders, David, Matija Strlic,
Capucine Korenberg, Naomi Luxford,
Karen Birkhölzer (eds), Archetype
Publica­tions in association with the British
Museum, London, 2013, with co-author
Rozemarijn Van der Molen. pp. 146-153.
“Sixteenth Century Life-casting
­Techniques, a reconstruction”, in The
Renaissance Workshop: The Materials and
Techniques of Renaissance Art, Saunders,
D., M. Spring, and A. Meek, (eds) (forthcoming 2013), Archetype Publications
in association with the British Museum,
London, forthcoming, with co-author
Pamela H. Smith.
ornaments applied on the exterior of the
Royal Palace in Amsterdam (not public).
2 A rather old publication but due to the
recent find of the Staffordshire Hoard of
current interest: Nijboer A.J., & J.E. van
Reekum, 1999: “Scientific analysis of the
gold disc-on-bow brooch”, in: Besteman,
J.C., J.M. Bos, D.A. Gerrets, H.A.
Heidinga & J. de Koning (eds.) The Excavations at Wijnaldum; Reports on Frisia in
Roman and Medieval times, A.A. Balkema
Rotterdam / Brookfield, pp. 203-215.
Laeven, Thijs en Janine van Reekum, 2008:
“Beroeps- en Competentieprofielen”,
Restauratoren Nederland, Den Haag.
3 Independent metal conservator-restorer
and advisor.
106
108
Lecturers
109
Paintings
Drs. Vera Blok
Drs. Emilie Froment
Kate Seymour MA
Drs. Maartje Stols-Witlox
v.r.blok@uva.nl
e.m.froment@uva.nl
k.seymour@sral.nl
m.j.n.stols-witlox@uva.nl
1 Mondrian in the Stedelijk Museum
1 PhD-research (ongoing): Consequences
1 FP7-EU IMAT (ENV-NMP.2011.2.2-5)
1 PhD-research (ongoing): ‘A perfect
Amsterdam: Research and conservation
of five early abstract paintings.
2 Blok, Vera: “Mondrian in the Stedelijk
Museum Amsterdam: Research and conservation of five early abstract paintings”.
In Zeitschrift für Kunsttechnologie und
Konservierung, 25, 2011, heft 2.
3 Freelance conservator-restorer at
Cobra Museum voor Moderne Kunst
Amstelveen.
Freelance conservator-restorer at ceiling
paintings in the Trippenhuis Amsterdam.
of wax-resin lining for the conservation
and restoration of 17th century Dutch
paintings on canvas.
2 Froment, E., M. van Eikema Hommes,
“The darkness of the nocturnal conspiracy
of Claudius Civilis by Govert Flinck
and Jürgen Ovens (1659-1662) in the
Royal Palace Amsterdam”, In: ICOM-CC
16th Triennial Conference Lisbon 19-23
September 2011: preprints [cd-rom].
Bridgland, Janet (Editor). ICOM Committee for Conservation (Corporate Author).
Critério-Produção Grafica, Lda. (2011).
Eikema Hommes, M. van, E. Froment,
“The decoration programme in the
­galleries of the Royal Palace Amsterdam:
a harmonious interaction between painting,
architecture and light?”, in catalogue of
the exhibition ‘Opstand als Opdracht’,
Stichting Royal Palace Amsterdam,
July 2011, pp. 34-53.
[2011-2014]: Intelligent Mobile Multipurpose Accurate Thermo-Electrical (IMAT)
Mild Heating Device for Conservation
of Cultural Heritage Assets.
Materials and methods of paste lining
for the reinforcement of canvas paintings:
documentation, functionality and conservation (liningp) (2011-2014) – proyecto
4166836-HAR2011-24217 (Spain).
2 Seymour, Kate, “Teaching adhesive
principles to conservation students: sine
scientia ars nihil est – without knowledge
skill is nothing”. In Book. Adhesives and
Consolidants in Painting Conservation:
proceedings of the international conferen­ce
held at the National Portrait Gallery,
London, 6 May 2011.
Fife, G.R., J. van Och, B. Stabik, N. Miedema, K. Seymour, R. Hoppenbrouwers: “A
package deal: the development of tissue gel
composite cleaning at SRAL”. In: ICOM-CC
16th Triennial Conference Lisbon 19-23
September 2011: preprints [cd-rom].
Bridgland, J., (Editor). ICOM Committee
for Conservation (Corporate Author).
Critério-Produção Grafica, Lda. (2011).
3 Head of Education, SRAL.
ICOM-CC Sculpture, Polychromy and
Architectural Decoration working group
coordinator.
ground’ Historical recipes for preparatory
layers for oil paintings in North West
Europe 1550-1900. A critical analysis and
recipe reconstructions.
2 Stols-Witlox, M., (2011). “Historical
restoration recipes: the cleaning of paintings
1600-1900”. In: ICOM-CC 16th Triennial
Conference Lisbon 19-23 September 2011:
preprints [cd-rom]. Bridgland, Janet (Editor). ICOM Committee for Conservation
(Corporate Author). Critério-Produção
Grafica, Lda. (2011).
Stols-Witlox, M. (2012). “Grounds for easel
painting, 1400-1900” in: Hill Stoner, Joyce,
Rushfield, Rebecca (eds.) Conservation
of Easel Paintings, London, Amsterdam:
Routledge.
3 Member core research team: Science 4
Arts Project “PAinT: Alterations in Time”.
Stols-Witlox schilderijenrestauratie.
108
110
Lecturers
111
Lecturers
Textiles
Wood and furniture
Drs. René Lugtigheid
Ir. Sylvia Nijhuis
Herman den Otter
d.o.r.lugtigheid@uva.nl
s.m.nijhuis@uva.nl
h.denotter@uva.nl
1 PhD research (ongoing): Catholic
1 Frames and their restoration, the frame
1 PhD-research (ongoing): André-Jacob
liturgical textiles in The Netherlands: past,
present and future. An investigation into
the causes of change. The research aims
to provide a basis for the cultural value
­assessment of this specific heritage.
2 All that glisters is not gold, the
­Appreciation of religious textiles in The
Netherlands and the formulation of
selection criteria for retention or disposal,
In: ICOM-CC 16th Triennial Conference
Lisbon 19-23 September 2011: preprints
[cd-rom]. Bridgland, Janet (Editor). ICOM
Committee for Conservation (Corporate
Author). Critério-Produção Grafica, Lda.
(2011) docs/1806_254_LUGTIGHEID_
ICOM-CC_2011.pdf.
2011: “A tale of two tapestries: Considerations of restoration, de-restoration, and
re-restoration” in M.M. Brooks and D.D.
Eastop: Changing views of textile conservation, the Getty Conservation Institute,
Los Angeles, pp. 284-289.
3 Member of the Committee of Research
Complaints Restauratoren Nederland.
Member Group Paramentica (http://paramentica.wordpress.com).
as an independent work of art, 2009.
Tripartite research into original transparant
coatings (or varnished) on furniture in The
Netherlands between 1600-1940. Partnership between RMA, RCE and UvA.
2 Nijhuis, Sylvia: “Gelatine en dierlijke
lijmen. Het belang van de fysische eigenschappen.” Cr 4, 2006.
3 Nijhuis Houtrestauratie, independent
enterprise for the purpose of conservation­
and restoration of wooden and gilded
objects.
Regularly employed as a restorer at RCE.
Roubo. L’art du menuisier.
2 Otter, Herman den: “De Nederlandse
meubelmakerij 1600-1940”. Amsterdam,
2011.
Herman den Otter: “De houten etspers in
het Rembrandthuis.” in: Kroniek van het
Rembrandthuis. 2009.
110
112
Other lecturers
113
Dr. Marjolijn Bol
Drs. René Hoppenbrouwers
Dr. René Peschar
Drs. Ink de Pree-Dommisse MA
Technical art history
m.a.h.bol@uva.nl
Paintings conservation-restoration;
preventive conservation
hoppenbrouwers@sral.nl
Science Consultant (esp. chemistry)
r.peschar@uva.nl
Art History, specialism the history
of ceramics
p.m.depree-dommisse@uva.nl
1 The Impact of Oil: A history of oil
painting in the Low Countries and its
consequences for the visual arts, 1350-1550
(NWO-project Utrecht University, University of Amsterdam and the Rijksmuseum).
Crafting Splendor and Examining Light.
The Artisan’s Contribution to the Study of
Optics, 1100-1700 (Max Planck Institute
for the History of Science Berlin).
2 Bol, Marjolijn, “Oil and the Translucent”. Varnishing and glazing in practice,
recipes and historiography, 1100-1600,
PhD ­Utrecht University 2012, 283 p.
Bol, Marjolijn and Ann-Sophie Lehmann,
“Painting Skin and Water. Towards a Material Iconography of Translucent Motifs
in Early Netherlandish Painting,” in: Watteeuw, Lieve and Lorne Campbell (eds.),
Colloquium Rogier van der ­Weyden in
context, 22-24 October 2009, Le dessin
sous-jacent dans la peinture.
3 Researcher at Max Planck Institute for
the History of Science, Berlin.
1 Safety in church buildings.
2 Hoppenbrouwers, R., J. van der Horst,
C. van Gestel, A. Vugts, “All hazards
approach: safety and accessibility for
religious heritage in the Province of
Limburg”, In: ICOM-CC 16th Triennial
Conference Lisbon 19-23 September 2011:
preprints [cd-rom]. Bridgland, Janet (Editor). ICOM Committee for Conservation
(Corporate Author). Critério-Produção
Grafica, Lda. (2011).
Fife, Gwendoline R., Jos van Och, Bascha
Stabik, Nada Miedema, Kate Seymour, and
René Hoppenbrouwers, “A package deal:
the development of tissue gel composite
cleaning at SRAL, In: ICOM-CC 16th Triennial
Conference Lisbon 19-23 September 2011:
preprints [cd-rom]. Bridgland, Janet (Editor). ICOM Committee for Conservation
(Corporate Author). Critério-Produção
Grafica, Lda. (2011).
3 Director SRAL.
iCOM-CC Working Group Education
and Training in Conservation, assistant
working group coordinator.
European Network for ConservationRestoration Education (ENCoRE),
­vice-chair.
112
1 Research (ongoing): Famille Noire
porcelain: stylistic and technical analysis.
Fakes and forgeries in ceramics.
2 Pree, Ink de, “Onder de loep genomen:
Kopieën van de Franse fabriek Samson”.
In: Vormen uit Vuur 184/185, pp. 76-83;
no. 5/2003.
Pree, Ink de, “Tussen traditie en individuele expressie: vijftien generaties Raku
pottenbakkers” in: Vormen uit Vuur 163,
pp. 34-42; no. 1/1998.
3 Independent editor on the subject
of ceramics.
Advisor to the Board of the Dutch
­Ceramics and Glass Society.
Member of the Oriental Ceramic Society.
114
Management
Drs. Angèle Goossens
Drs. Suzanne Maarschalkerweerd
Coordinator continuing education
a.t.f.p.goossens@uva.nl
History of Art student UvA (part-time)
Programme-manager
s.l.j.maarschalkerweerd-dechamps@uva.nl
Rosa Hoogenboom
Drs. Inge Tinbergen
Secretary continuing education
pe-CenR@uva.nl
History of Art student UvA
Programme-coordinator
i.l.tinbergen@uva.nl
Hanna de Lange
Secretary
secretariaat-C&R@uva.nl
History student UvA (part-time)
114
115
116
Alumni
116
117
Overview alumni
* AB
*This alumnus received his / her
Master’s degree after completing
the course in Conservation and
Restoration at the (former) ICN.
His / her qualifications are
equivalent to graduates that have
­completed the UvA PI program.
Marya Albrecht
marya.albrecht@live.nl
■ Discipline Paintings ■ MA thesis title Klein maar fijn. Loodwit
in fijne deeltjesgrootte. ■ Year of
MA graduation 2012 ■ Current
activities rio (UvA)
See pages 7 and 8 for more
information about MA and PI.
Stephanie Avril
post@stephanieavril.eu
■ Discipline Paintings ■ MA
thesis title De Heilige Agnes. Een
schilderij met pressbrokat uit de
Noordelijke Nederlanden. ■ Year
of MA graduation 2011 ■ Current
activities rio (UvA)
118
Roosmarijn van Beemen
rmcvanbeemen@gmail.com
■ Discipline Glass, ceramics and
stone ■ MA thesis title Lijm­
methoden in de restauratie van
gipsen afgietsels van antieke
beelden. ■ Year of MA graduation 2011 ■ Current activities
rio (UvA)
Sophie de Behault
■ Year of MA graduation 2012
Sanne van
Bergenhenegouwen
svbergenhenegouwen@gmail.
com
■ Discipline Book and paper
■ MA thesis title De constructie
en conservering van beweegbare
boeken; een case-study van de
Meggendorfer-Collectie, Bijzondere Collecties Amsterdam.
■ Year of MA graduation 2012
■ Current activities rio (UvA)
Nienke Besijn
nienkebesijn@gmail.com
■ Discipline Glass, ceramics and
stone ■ MA thesis title Een lichtje
laten schijnen over UV-lijmen.
Een onderzoek naar het gebruik
en veroudering van vier UV-lijmen
voor toepassing binnen de glas­
restauratie. ■ Year of MA graduation 2011 ■ Current activities
rio (UvA)
Julia van den Burg
julia.vandenburg@gmail.com
■ Discipline Paintings ■ MA thesis
title The hand of a Master; technical research into the paintings of
Jacob Backer (1608 / 09 -1651).
■ Year of MA graduation 2011
■ Current activities rio (UvA)
118
119
Frederike Burghout*
burghoutrestauratie@gmail.com
■ Discipline Glass, ceramics and
stone ■ MA thesis title Koude
beschildering op delfts witgoed
plastieken; een onderzoek naar
samenstelling, vervaardiging,
degradatie en conservering.
■ Year of MA graduation 2013
■ Current activities Freelance
conservator-restorer glass,
­ceramics and stone; coordinator
depots at Stichting tot beheer
Museum Boijmans van Beuningen
D F
Melissa Daugherty
m.e.daugherty@hotmail.com
■ Discipline Paintings ■ MA
thesis title Dilemma’s in de
restauratie; handreiking voor
de restauratie van schilderijen
met latere toevoegingen die
bijdragen aan de identificatie van
de geportretteerden. ■ Year of
MA graduation 2011 ■ Current
activities rio (UvA)
Tamar Davidowitz
tamardavidowitz@gmail.com
■ Discipline Metal ■ MA thesis
title Painted silver; the use of
colour on the Merkel table piece.
■ Year of MA graduation 2010
■ PI thesis title The Diana
­Automaton in the Collection
of the Rijksmuseum Amsterdam.
Year of PI graduation 2012
■ Current activities Junior metal
conservator-restorer at Rijks­
museum Amsterdam
Hannie Diependaal
J.M.S.Diependaal@uva.nl
■ Discipline Paintings ■ MA
thesis title De schilderkist van
­Breitner en de kleuren van
­Standage. ■ Year of MA graduation 2011 ■ Current activities
rio (UvA)
Nadine Faber
nadine.faber@gmail.com
■ Discipline Paintings ■ MA
thesis title ‘De mens’ terug in
restauratie. Het belang van
kennis over visuele perceptie
en onderzoeksmethoden uit de
psychologie voor restauratoren.
■ Year of MA graduation 2010
■ Current activities Visual artist
G
Judith Geerts
judith@nachos.tk
■ Discipline Book and paper
■ MA thesis title Lichtschade
aan gekleurd werk op papier;
onderzoek naar een gedifferen­
tieerd schadebeeld. ■ Year of
MA graduation 2010 ■ Current
activities rio (UvA)
Auke Gerrits
auke_gerrits@hotmail.com
■ Discipline Wood and furniture
■ MA thesis title Een onderzoek
naar kastsloten uit de 18e eeuw.
■ Year of MA graduation 2011
■ Current activities rio (UvA)
Sophie Glerum
s.a.glerum@gmail.com
■ Discipline Wood and furniture
■ MA thesis title Afwerklagen­
op meubelen 1800 -1900;
reconstructies van negentiendeeeuwse afwerklagen op basis van
onderzoek naar contemporaine
bronnen. ■ Year of MA graduation 2011 ■ Current activities
rio (UvA)
Dave van Gompel*
dave.vangompel@gmail.com
■ Discipline Wood and furniture
■ MA thesis title Restaureren met
stickers; het gebruik van transfer­
stickers in de meubelrestauratie.
■ Year of MA graduation 2010
■ Current activities Freelance
conservator-restorer
Cornelia Görlich
■ Year of MA graduation 2011
Tess Graafland
tess.graafland@gmail.com
■ Discipline Wood and furniture
■ MA thesis title Originele ver­
gulding op negentiende-eeuwse
pâtelijsten. Onderzoek naar
historische verguldtechnieken.
■ Year of MA graduation 2012
■ Current activities rio (UvA)
Lousco Grasman
lousco@gmail.com
■ Discipline Paintings ■ MA
thesis title Schitterende illusie;
de weergave van metalen in de
zeventiende-eeuwse Hollandse
schilderkunst ■ Year of MA
­graduation 2008 ■ PI thesis title
Een materiële toeschrijving aan
Pieter Fontijn (1774 -1839); onderzoek naar en restauratie van twee
portretten op doek. Year of
PI graduation 2010 ■ Current
activities Independent private
conservator-restorer, working in
a shared workshop in Haarlem
H
120
Jeroen van Halder
j.halder@upcmail.nl
■ Discipline Metal ■ MA thesis
title Organisch malmateriaal in
cire perdue mallen. Verkenning
naar de praktijk in de Italiaanse
Renaissance. ■ Year of MA graduation 2012 ■ Current activities
rio (UvA)
Jessica Hensel
jessicahensel@gmail.com
■ Discipline Historic interiors ■
MA thesis title De toxiciteit van
het pigment orpiment in histo­
rische interieurs. ■ Year of MA
graduation 2013 ■ Current activities Internship at RCE and RMO
Jonathan Gration
info@historischeinterieurs.nl
■ Discipline Historic interiors
■ MA thesis title Oriëntaals Hees­
wijk; bestudering & reconstructie
van een lakwerk interieur. ■ Year
of MA graduation 2011 ■ Current
activities J. Gration Historische
Interieurs, - research, restoration
and advice
Annemieke Heuft
a_heuft@hotmail.com
■ Discipline Historic interiors
■ MA thesis title Koolteer voor de
schilder; een materiaalhistorische
studie van een 19e-eeuwse kool­
teerverf op de orgelkas in de
Westerkerk in Enkhuizen. ■ Year
of MA graduation 2011 ■ Current
activities rio (UvA)
Sophie van Gulik
sophievangulik@hotmail.com
■ Discipline Historic interiors
■ MA thesis title Lodewijk
­Napoleon op de Dam; de ver­
bouwing van stadhuis tot paleis
en het onderzoek naar deze
verdwenen periode. ■ Year of
MA graduation 2008 ■ Current
activities Employee at Lyppens
­juwelier, Veilinggebouw de
Zwaan and Kramer Kunst en
Antiek
Corina den Hollander
■ Year of MA graduation 2009
Marjolein Homan Free
m.e.homanfree@gmail.com
■ Discipline Textiles ■ MA thesis
title Het gebruik van Vanish
Oxi Action Intelligence plus op
historisch textiel. Onderzoek naar
de schadelijke werking van een
huishoudmiddel voor het reinigen­
van historisch textiel. ■ Year of
MA graduation 2010 ■ Current
activities rio (UvA)
120
121
I J K
Zuhura Iddi
zuhura_iddi@hotmail.com
■ Discipline Paintings ■ MA
thesis title Droge reiniging; het
effect van zes soorten residuen
op ongeverniste olieverflagen.
■ Year of MA graduation 2013
Ellen Jansen
ellenjansen@me.com
■ Discipline Contemporary art
■ MA thesis title Survival of the
Survival Series. Conserverings­
strategieën voor lichtkranten met
een intern geheugen. ■ Year of
MA graduation 2010 ■ PI thesis
title Go with the Glow. Behande­
lingsmogelijkheden voor een
kunstwerk met een fosforesceren­
de verflaag. Year of PI graduation 2012 ■ Current activities
Lecturer Contemporary art (UvA
C&R); independent conservatorrestorer of contemporary art
Thijs Janssen
jnssn.thijs@gmail.com
■ Discipline Wood and furniture
■ MA thesis title Reconstructie
van robbellijsten met behulp van
moderne technieken. Een onder­
zoek naar 3D scannen, CNC-frezen
en 3D printen. ■ Year of MA
graduation 2012 ■ Current activities rio (UvA)
Oleg Karuvits
karuvits@gmail.com
■ Discipline Paintings ■ MA thesis
title Verkleuring als gevolg van
het schilderen op ongegrondeerd
doek en washarsbedoeking; naar
aanleiding van ‘De nachtelijke
samenzwering van Claudius Civilis
in het Schakerbos’ van Govaert
Flinck and Jurgen Ovens. ■ Year
of MA graduation 2008 ■ PI
thesis title Schildertechniek van
Philips Wouwerman (1619 -1668).
Year of PI graduation 2010
■ Current activities Independent
conservator-restorer of paintings;
conservator-restorer at the
Mauritshuis
Rachelle Keller
rachellekeller@hotmail.com
■ Discipline Book and paper ■
MA thesis title Vergipsing; een
bijzondere schade bij perka­
menten boekbanden. ■ Year of
MA graduation 2011 ■ Current
activities rio (UvA)
Diederik Kits Nieuwenkamp
diederikkn@casema.nl
■ Discipline Wood and furniture
■ MA thesis title De aanvulling
van lacunes in een transparante
afwerklaag met verouderingstex­
tuur op een houten ondergrond:
een buiten het object gevormde
aanvulling met textuur. ■ Year of
MA graduation 2011 ■ Current
activities rio (UvA)
Roos Kliphuis
rooskliphuis@hotmail.com
■ Discipline Book and paper
■ MA thesis title De collectie
Carel Visser; een onderzoek naar
foxing op Japanse stijl papier.
■ Year of MA graduation 2012
■ Current activities rio (UvA)
Femke van der Knaap
femkevanderknaap@gmail.com
■ Discipline Paintings ■ MA thesis title Luitsen Kuiper, de praktijk
van een restaurator. ■ Year of MA
graduation 2011 ■ Current activities rio (UvA)
Marjolein Koek
marjoleinkoek@hotmail.com
■ Discipline Textiles ■ MA thesis
title Behandeling van vergeling
in struisvogelveren; onderzoek
naar de oorzaak van vergeling
en mogelijke reiniging van
struisvogelveren als onderdeel
van een kostuum. ■ Year of MA
graduation 2012 ■ Current activities rio (UvA)
Jorinde Koenen
j.koenen@uva.nl
■ Discipline Paintings ■ MA thesis
title In de wolken met Willen
Beurs? Een onderzoek naar de
waarde van ‘De groote waereld in
‘t kleen geschildert […]’ (1692) van
Willem Beurs als kunsttechnologische bron. ■ Year of MA graduation 2011 ■ Current activities
rio (UvA)
Minette Kuijf
mkuijf@hotmail.com
■ Discipline Historic interiors
■ MA thesis title Giovanni de
Groot & zijn muurschilderingen
in het voormalige Amsterdamse
stadhuis op de Dam. ■ Year of
MA graduation 2008 ■ Current
activities Freelance conservatorrestorer of painted surfaces
L
122
Suzanne van Leeuwen
suzanneleeuwen@hotmail.com
■ Discipline Metal ■ MA thesis
title Authentiek, vervalst,
­gerestaureerd of pastiche? Een
onderzoek naar twee Renaissance juwelen uit de collectie
Mannheimer in het Rijksmuseum
Amsterdam. ■ Year of MA graduation 2012 ■ Current activities
rio (UvA)
Julia Leunge
julia.leunge@hotmail.com
■ Discipline Metal ■ MA thesis
title Acetylacetone; onderzoek
naar de reiniging van messing op
meubelen. ■ Year of MA graduation 2012 ■ Current activities
rio (UvA)
Stefanie Litjens
■ Year of MA graduation 2010
Year of PI graduation 2012
Laura Koster
laurakoster103@gmail.com
■ Discipline Wood and furniture
■ MA thesis title Onderzoek naar
de restauratiegeschiedenis van
de zeventiende-eeuwse Zeeuwse
kast. ■ Year of MA graduation
2012 ■ Current activities rio (UvA)
123
MN O
Marije Meddeler
marije.meddeler@gmail.com
■ Discipline Metal ■ MA thesis
title Het etsen van zilver; techno­
logie, toepassing en herkenning.
■ Year of MA graduation 2011
■ Current activities rio (UvA)
Anna-Katrien Mol
katimol@outlook.com
■ Discipline Metal ■ MA thesis
title Archeologisch Roest; een
onderzoek naar de mogelijke
­effecten van de opslag van
archeo­logisch ijzer tijdens en
direct na archeologische veldwerkzaamheden. ■ Year of MA
graduation 2012 ■ Current activities Archaeological researcher;
employee at Museum Het Schip
Rozemarijn van der Molen*
rozemarijn.vandermolen@tate.
org.uk
■ Discipline Metal ■ MA thesis
title Droogijsstralen, dé
reinigings­techniek voor metalen?
■ Year of MA graduation 2010
■ Current activities Assistant
Sculpture conservator-restorer,
Tate, London
Kim Mulder*
k.mulder.1984@gmail.com
■ Discipline Book and paper
■ MA thesis title Handaanvezelen­
op de onderdruktafel met
toevoeging van bladvormende
additieven aan de pulpoplossing.
Het verkrijgen van een gelijkmatige papierlaag met optimale
vezelverdeling. ■ Year of MA
graduation 2012 ■ Current activities Book and Paper conservatorrestorer at The British Library,
London, United Kingdom
Helbertijn Krudop
helbertijnkrudop@hotmail.com
■ Discipline Wood and furniture
■ MA thesis title De rokken
gelicht; een onderzoek naar de
constructie van Nederlandse acht­
tiende-eeuwse rococo commodes.
■ Year of MA graduation 2011
■ Current activities rio (UvA)
122
Alexandra Nederlof
alexan_ned@hotmail.com
■ Discipline Book and paper
■ MA thesis title Vetkrijt, waskrijt
of oliekrijt? Welk gekleurd krijt
heeft Vincent van Gogh in zijn
tekeningen gebruikt? Een onderzoek naar gekleurd krijt met een
bindmiddel van was, olie of vet in
de periode 1850 -1910. ■ Year of
MA graduation 2011 ■ Current
activities rio (UvA)
Saskia van Oudheusden
s.v.oudheusden@gmail.com
■ Discipline Paintings ■ MA
thesis title De uitvoering van washars bedoekingen door Johannes
Albertus Hesterman (1848 -1916)
en zonen. Een onderzoek naar
hun werkwijze en materialen.
■ Year of MA graduation 2011
■ Current activities rio (UvA)
P R S
Arie Pappot*
a.pappot@rijksmuseum.nl
■ Discipline Metal ■ MA thesis
title Lokale behandeling van
bronspest; met natriumsesqui­
carbonaatoplossingen. ■ Year of
MA graduation 2011 ■ Current
activities Junior metal conservator-restorer at Rijksmuseum
Amsterdam
Jean Marieke Poot
jeanmarieke@hotmail.com
■ Discipline Book and paper
■ MA thesis title Lichtschade?
Een onderzoek naar de rand­
verkleuringen op aquarellen uit
de Druckercollectie. ■ Year of
MA graduation 2010 ■ PI thesis
title Een portret met problemen.
De behandeling van Mevr. Tilly
Mengelberg-Wubbe: een pastel
uit een particuliere collectie.
Year of PI graduation 2012
■ Current activities Freelance
paper conservator-restorer
Martine Posthuma de Boer
mposthumadeboer@gmail.com
■ Discipline Historic interiors
■ MA thesis title De verdonkering
van goudleer in Nederland. Een
karakterisering van de degradatie­
verschijnselen in de zilver- en
vernislagen bij twee case-studies:
Sint Pietershof Hoorn en Wees­
huis der Hervormden Schiedam.
■ Year of MA graduation 2012
■ Current activities rio (UvA)
Daphne Reijs
ds_reijs@hotmail.com
■ Discipline Textiles ■ MA thesis
title De oudheid bewaard voor de
toekomst: een onderzoek naar de
conservering van archeologisch
textiel. ■ Year of MA graduation
2010 ■ PI thesis title Van Frag­
ment tot Vaandel; conservering
van een rederijkersvaandel uit
1750. De behandeling van een
ernstig gedegradeerd achttiendeeeuws vaandel met een twee­
zijdige beschildering. Year of
PI graduation 2011 ■ Current
activities Independent entrepreneur: 2Restore Textielrestauratie
Koosje Ruijgrok
koosjeruijgrok@gmail.com
■ Discipline Book and paper
■ MA thesis title Het restaureren
van de Enkhuizer librije; ethiek en
esthetiek binnen een restauratieproject. ■ Year of MA graduation 2009 ■ Current activities
Designer, illustrator
124
Willianne van der Sar
williannevds@hotmail.com
■ Discipline Historic interiors
■ MA thesis title De marouflage­
techniek van Jan Dunselman in
de HH Laurentius en Elisabeth
Kathedraal in Rotterdam; een
­materiaaltechnisch onderzoek aan
Het Laatste Avondmaal. ■ Year of
MA graduation 2010 ■ PI thesis
title The Application of Solvent
Gels in the Conservation of
­Historic Interiors. Two case studies.
Year of PI graduation 2012 ■
Current activities Color & Conser­
vation – Conservator-restorer in
private practice, conservation
of historic interiors, analysis of
painted surfaces, microscopist
Hilde Schalkx*
hildeschalkx@gmail.com
■ Discipline Book and paper
■ MA thesis title Het spoelen
van watergevoelige objecten van
papier: capillary unit of blotter
wash? ■ Year of MA graduation
2010 ■ Current activities Book
and paper conservator-restorer at
Hoogduin Papierrestauratoren in
Delft; involved in projects with a
more theoretical component, for
example developing a condition
assessment survey for libraries
and writing a conservation policy
for the Utrecht Archives
124
125
Rosan Scheres
rosanscheres@gmail.com
■ Discipline Historic interiors
■ MA thesis title De verborgen
Cuypers in het Rijksmuseum; een
Maastrichtse muurschildering in
een Amsterdams museum.
■ Year of MA graduation 2009
■ PI thesis title Een Kamerscherm
Ontvouwd Year of PI graduation 2011 ■ Current activities
Independent researcher and
conservator-restorer of historic
interiors interior design and upholstery; lecturer historic interiors
at the UvA C&R
Elisa Schöne
info@elisaschonekunsten.nl
■ Discipline Contemporary art
■ MA thesis title Wit-goed-wit.
Een onderzoek naar de mogelijk­
heden tot het exposeren van een
bed in Joep van Lieshout’s Mobile
Home for Kröller-Müller. ■ Year
of MA graduation 2008 ■ PI thesis title When soft rock becomes
hard rock. De behandeling van
Mein Treuer Wanderstab (1987)
van Evelyne Janssen. Year of
PI graduation 2010 ■ Current
activities Freelance / private
conservator-restorer in Utrecht
Merel van Schrojenstein
Lantman
merel.lantman@gmail.com
■ Discipline Historic interiors
■ MA thesis title Herkenbaarheid
van houtimitaties uit de periode
1750 -1800 in de Noordelijke
Nederlanden. ■ Year of MA
graduation 2010 ■ PI thesis
title De ideale staat van het
object. Vier 17e - eeuwse deuren
in de Hof van Moerkerken te
Mijnsheeren­land. Toepassing
van een methodo­logie. Year
of PI graduation 2012 ■ Current
activities Independent conservator-restorer of painted interior
components
Hinke Sigmond
hinkesigmond@gmail.com
■ Discipline Historic interiors
■ MA thesis title Sprekend
verleden, bron voor de toekomst;
de toepassing van oral history in
historische binnenruimten en de
restauratiegeschiedenis van de
jaren ’70. ■ Year of MA graduation 2011 ■ Current activities
rio (UvA)
Susan Smelt
susansmelt@gmail.com
■ Discipline Paintings ■ MA
thesis title Regeneraties uit het
verleden bieden geen garantie
voor de toekomst. Hoe de wens
van Max von Pettenkofer voor het
onveranderd behouden van het
schilderij toch blijkt bij te dragen
aan het verval van het schilderij.
Het ‘portet van Otto Heurnius’
[SA 3339] als casus voor de invloed
van de regeneratiebehandeling
en de washarsbedoeking. ■ Year
of MA graduation 2010 ■ PI thesis
title Het onderzoek naar en de
restauratie van het 17e - eeuwse
Familieportret van Gillis van
Tilborgh uit de collectie van het
Koninklijk Kabinet van Schilde­
rijen Mauritshuis. Year of PI
graduation 2012 (cum laude)
■ Current activities Working both
as a freelance paintings conservator-restorer and on contract
Saskia Smulders - de Jong
smuldersdejong@gmail.com
■ Discipline Wood and furniture
■ MA thesis title Chemische
beitsen; een onderzoek naar de
lichtechtheid en identificatie
van drie metaalzout-beitsen op
eikenhout. ■ Year of MA graduation 2010 ■ PI thesis title Besluit­
vorming rondom een Koninklijke
Toilettafel; een omvangrijke
restauratie van een Italiaans meubel uit de 19de eeuw van gezwart
hout en ingelegd met natuur­
steen. Year of PI graduation
2012 ■ Current activities Junior
furniture conservator-restorer at
the Rijksmuseum Amsterdam
Joni Steinmann
jmisteinmann@gmail.com
■ Discipline Textiles ■ MA thesis
title ‘Majestueus & Hemels’
Negentiende-eeuwse blauwe
kleurstoffen in de Rijksmuseum
kostuumcollectie. Vroege kleur­
stoffen in kostuums; onderzoek
naar de staat van textiel in relatie
tot de kleurstof. ■ Year of MA
graduation 2010 ■ Current activities rio (UvA)
Lise Steyn
lisesteyn@gmail.com
■ Discipline Paintings ■ MA thesis
title Van Gogh’s cobalt blue;
­research into the possible causes
for trace elements found by
means of SEM-EDX in two distinct
variants of cobalt aluminate used
by Vincent van Gogh 1886 -1890.
■ Year of MA graduation 2011
■ Current activities rio (UvA)
T V
Marijke Top
topmarijke@gmail.com
■ Discipline Glass, ceramics and
stone ■ MA thesis title Chinees
porselein en de kunst van het
lijmen. Een onderzoek naar de
verdonkering van breuklijnen.
■ Year of MA graduation 2011
■ Current activities rio (UvA)
Tamara Venema
tsvenema@hotmail.com
■ Discipline Wood and furniture
■ MA thesis title De boeken­
kasten in de bibliotheek van
het Rijksmuseum. ■ Year of MA
graduation 2010 ■ PI thesis title
Restauratie aan een commode.
Year of PI graduation 2012
■ Current activities Conservatorrestorer at Period Furniture
Conservation, LLC, New York
126
Lisette Vos
lisette.vos@gmail.com
■ Discipline Paintings ■ MA
thesis title Het retoucheren van
‘zwarte’ verven: een verheldering.­
De verf en de retouche in 17deeeuwse schilderijen van Neder­
landse makelij. ■ Year of MA
graduation 2008 ■ PI thesis title
Op jacht naar Dirck Stoop; de
restauratie van twee schilderijen
en onderzoek naar de schilder­
techniek van een 17de-eeuwse
kunstenaar. Year of PI graduation 2010 ■ Current activities
On contract at the Rijksmuseum
Amsterdam conservation-restoration department
127
W
Boudewien Westra
boudewienwestra@hotmail.com
■ Discipline Wood and furniture
■ MA thesis title Onderzoek naar
de originaliteit van de afwerklaag
op de ladekast in het Jachthuis
Sint Hubertus. ■ Year of MA
graduation 2012 ■ Current activities rio (UvA)
Karolien Withofs
mail@karolienwithofs.com
■ Discipline Contemporary art
■ MA thesis title Elektrisch aan­
gedreven kunstwerken; een kijk
op praktijk met 2 casestudies van
Jan van Munster. ■ Year of MA
graduation 2010 ■ PI thesis title
Transformator en Transformatie.
Het sturen van veranderingen
in een kunstwerk van Thomas
Hirschhorn. Year of PI graduation 2012 ■ Current activities
Private conservator-restorer
Guus Verhaar
guus.verhaar@gmail.com
■ Discipline Free Master ■ MA
thesis title The investigation of
the use of ion chromatography
for identification of early stages
of glass sickness. ■ Year of MA
graduation 2012 ■ Current
activities Technical analyst at the
Rijksmuseum Amsterdam
Nicolas Verhulst
verhulst.nicolas@gmail.com
■ Discipline Glass, ceramics and
stone ■ MA thesis title Onder­
zoek van oppervlaktelagen op
Maaskalksteen in de binnenhal
van het stadhuis te Maastricht.
■ Year of MA graduation 2010
■ PI thesis title The Ince Blundell
composite marble statue of a
man with an ivy wreath – ‘Marcus
­Aurelius’: revisited / restored.
Year of PI graduation 2012
■ ­Current activities Petracon:
condition survey, conservation
and restoration of stone-like
­materials and art historical
research; coordinator module
‘stone’ at the UvA C&R
Nienke Woltman
nienkewoltman@gmail.com
■ Discipline Paintings ■ MA thesis title Het geheim van vluchtige
oliën. De toevoeging van
vluchtige oliën aan het olieverfmedium in de zestiende-eeuwse
schilderpraktijk van de Lage
Landen. ■ Year of MA graduation­
2010 ■ PI thesis title Op zoek naar
Colijn de Coter; techniek, verval
of restauratie? Year of PI gradu­
ation 2012 ■ Current activities
Junior conservator-restorer
paintings at the Rijksmuseum
Amsterdam
126
Lidwien Wösten
lwosten@hotmail.com
■ Discipline Paintings ■ MA
thesis title Blotting. Onderzoek
naar het gebruik van blotting in
15de- en 16de-eeuwse schilderijen
van de Leidse School. ■ Year of
MA graduation 2010 ■ PI thesis
title ‘Gy ziet hier in de zaal by
meenigt’ aan de wanden. Een
onderzoek naar de VOC portret­
ten van Pieter van de Werff.
Year of PI graduation 2012
■ Current activities Internship
at The Hamilton Kerr Institute,
University of Cambridge
Z
Anna Zwagerman
annazwagerman@gmail.com
■ Discipline Historic interiors
■ MA thesis title Sandstone,
marble and paint; an investigation into the history of the walls
and vaulted ceilings of the main
public spaces in Amsterdam’s
former Town Hall, with a side
note to Atlas’sprera. ■ Year of MA
graduation 2009 ■ PI thesis title
Conservation 4 Access: Conserva­
tion for access at Penrhyn Castle,
Wales; visitor impact on the physical condition of a 19th century
National Trust Property Year
of PI graduation 2011 ■ Current
activities HLF / Icon (Institute of
conservation) preventive conservation intern at de National Trust
for Scotland (NTS)
Colophon
Publication Faculty of Humanities, Conservation and restoration of cultural heritage
Compilation and editing Angèle Goossens
Editing summary’s René Peschar
Design Anke Broeren
Photography T. Beentjes [inside cover-1], L. Biçaçi [pp. 6, 9, 19, 22, 26, 98, 101, 102-1, 103, 106, 108-2,
110, 111-2, 112-2, 113, 114-1, 114-2, 114-3, 114-4], D. Blits [p. 104-2], M. Bol [p. 112-2],
J. Borstlap [p. 108-1], I. Broersma and L. Wolfers [inside cover-2], D. Brouwer [p. 102-2],
J. van den Burg [pp. 36, 82], A.H. Christensen [p. 18], P. Fahrenfort [p. 39], J.A. Glatigny
[p. 17], S.A. Glerum [p. 89], J. Govaers [p. 100-1], T. Graafland [p. 44], K. Groeneveld
[p. 107-2], A. Heuft [p. 48], E. Jansen [p. 4 / 5], T. Janssen [p. 20 / 21], R. Klein Gotink
[p. 111-1], I. Kneepkens [p. 56], L. Kolkena [p. 25], E. Lampe [p. 109-2], S. van Leeuwen
[p. 61], K. van Lookeren Campagne [p. 10 / 11], R. Lugtigheid [p. 116 / 117], M. Meddeler
[p. 63], A. Nederlof [p. 64], E. Nijhoff Asser [p. 96 / 97], J. Oerlemans [pp. 12, 99],
M. Posthuma de Boer [p. 68], RMA [p. 93], M. van Schrojenstein Lantman [p. 72],
M. Selten [p. 100-2], K. Seymour [p. 109-1], H. Sigmond [p. 74], S.M.A.K. [p. 91],
C. de Smet [p. 9-2], S. Smulders-de Jong [p. 79-1], M. Stols-Witlox [p. 30 / 31],
M. Svensson [p. 76], I. Tinbergen [p. 104-1], V. Veenemans [p. 107-1], T.S. Venema
[p. 84], N. Verhulst [p. 88], P. Voeten [p. 114-5], E. de Witte [p. 27]
Press Lecturis bv, Eindhoven
Binding Hexspoor bv, Boxtel
Edition 500
With special thanks to all staff members of conservation and restoration of cultural
heritage and all alumni who have kindly cooperated.
Copyright for the specific components lies with the authors and the photographers. The copyright over
the whole lies with the editor. No parts of this publication may be reproduced and or published by any
means, mechanical, photocopy, microfilm, or other without the written permission of both the copyright
owner and the editor of the year book.