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The beauty of colour
© Swiss Gemmological Institute SSEF
ScoCsh$Gemmological$Associa9on$E$Conference,$
Saturday$3$May$2014$
The quest for "Kashmir" sapphires and "Burma" rubies
Origin determination of gemstones:
Possibilities, Challenges and limitations !
Dr.$Michael$S.$Krzemnicki,$Swiss$Gemmological$Ins9tute$SSEF$
$
Photos$©$M.S.$Krzemnicki,$SSEF,$except$where$indicated$otherwise$
The$Star%of%Kashmir%
Sapphire$from$Kashmir$of$approx.$20$ct,$$
Geneva$May$2013,$3.5$mio$US$$
SSEF$Test$Report$No.$66221$
Burmese ruby
A$superb$ruby$of$6.04$ct$set$
in$a$ring$with$diamonds$by$
Etcetera.$
$
$
Sold$for$a$world$auc9on$
record$price$of$US$$551‘000$
per$carat$(Chris9e‘s$Hong$
Kong,$May$2012).$
$
SSEF$report$59356$
&$Appendix.$
$
Photo$©$Chris9e‘s$
A$number$of$sources$of$coloured$stones$are$known$since$historic$9mes$and$their$gems$
have$been$treasured$over$centuries$for$their$beauty$and$rarity.$
The$relevance$of$the$origin$of$a$gemstone$
E  emo9on$
E  connec9ng$to$history$
E  a$label$
E  for$investment$
Bagan,$Burma$©$P.$Boegli,$Flickr.com$
Jose$Boomsma:$Tribute$to$Rothko$EBlue$
Relevance$of$origin$
$
Prices$
$
Auc9on$
$
$
Etcetera$ruby$!$
$
Emo9onen$
$
Label$
$
Sicherheit,$Wertanlage,$investment,$$
$
Exper9se$as$with$art$work$(Rothko)$
$
$
$
Rothko:$un9tled$
Origin determination is always an expert opinion !
The$origin$determina9on$of$gemmological$laboratories$is$always$based$on$scien9fic$analyses$(e.g.$
trace$element$composi9on,$absorp9on$spectra,$Raman$microspectrometry$etc.)$and$me9culous$
microscopic$observa9ons.$
$
Thus$it$is$possible$that$two$different$labs$may$issue$a$different$origin$for$a$given$gemstone.$
Origin determination:
Combining(
classical(
approaches(
with(
advanced(
scienti5ic(
analytical(
methods(
Near$Bawpadan$in$Mogok$
The$origin$of$a$gemstone$on$a$report$is$
always$an$opinion$of$experts,$indica9ng$
its$most$probable$geographic$origin.$
$
It$describes$stones$which$originate$from$a$
mining$opera9on$in$that$geographic$area.$
$
It$is$related$to$the$geological$seCng$$
characteris9c$for$the$origin$(mining$area).$
$
The$origin$is$expressed$based$on$wellE
established$criteria$(e.g.$inclusions,$
chemical$composi9on...).$
$
$
Challenges:$$
E $New$mining$areas$are$discovered.$
E$The$analy9cal$methods$get$more$and$
more$sophis9cated.$
© SSEF Swiss Gemmological Institute
Origin$determina9on$at$SSEF$is$relying$on:$
$
E $$scien9fically$and$gemmologically$highly$
educated$staff$$
E $sophis9cated$analy9cal$instrumenta9on$
E $reference$samples$from$different$mines$
E $con9nuous$research$
E $long$established$experience$
Photo © H.A. Hänni, SSEF 2004
Four steps of origin determination:
$
1)$Observa9ons$and$collec9on$of$analy9cal$data$
$
2)$Interpreta9on$of$observa9ons$and$data$
$
3)$Weigh9ng$of$evidences$and$consistency$check$
$
4)$Conclusion(s)$
$
$$
Important:$
Independent$assessment$of$a$gemstone$by$second$(third$
etc...)$expert$(gemmologist)$and$mutual$discussion$!!$
Deposits connected to Pan-African
tectonometamorphic events
Distribu9on$of$corundum$deposits$
connected$to$PanEAfrican$tectonoE
metamorphic$events$(750E450$ma)$by$the$
collision$of$eastern$and$western$
Gondwana.$
$
In$midEJurassic$(about$160$ma),$India$
started$to$drig$towards$north.$
marble-hosted deposits
Distribu9on$of$marbleEhosted$ruby$deposits$along$the$Himalayan$
orogeny$(45E5$ma)$due$to$the$collision$between$the$Indian$plate$
and$Eurasia.$$
Dahaw$mine$:$Mogok$East$
Corundum from alkali basalts
after Jobbins & Berrangé, 1981
Ter9ary$and$quaternary$
basalts$and$related$
corundum$deposits$in$
SouthEEast$Asia.$
Pailin!
Jobbins & Berrangé, 1981!
Analytical instruments used for
origin determination at SSEF
$
E 
E 
E 
E 
E 
XEray$fluorescence$(EDXRF)$
Raman$Microspectrometry$
FTIR$Infrared$Spectrometry$
UVEVisENIR$Spectrophotometer$
Photoluminescence$
Eventually:$
E  LAEICPEMS$(laser$abla9on$induc9vey$coupled$plasma$mass$spectrometry)$
E  LIBS$(laser$induced$breakdown$spectroscopy)$
Raman
microspectrometry
UV-Vis Spectrometry
from
© SSEF Swiss Gemmological Institute"
H.A. Hänni, Journal of Gemmology 1994!
Chemical data versus spectroscopic data
Basaltic!
Burma!
Ceylon!
Kashmir!
© SSEF Swiss Gemmological Institute!
Laser Ablation Inductively Coupled Plasma
Mass Spectrometry LA-ICP-MS
With$Dr.$Thomas$Pehke$$
at$the$Geochemical$Lab,$$
University$of$Berne,$Switzerland$
Laser ablation
© T. Pettke,, University Berne
Local$hea9ng$and$vaporiza9on$
Raw
data
Data
processing
homogeneous(signal(
LA-ICP-MS Pearls
100000000
Ca
counts
10000000
1000000
Mn
100000
Ba
I
Mg
10000
1000
Integration time
100
10
30
40
50
60
70
80
90
100
110
120
time (sec.)
Setting(of(integrals(for(data(processing(is(easy(
From:$P.$Halicki,$SSEF$(Masterthesis)$
Data processing
Surface$contamina9on$!$
Surface$contamina9on$!$
Spikes$!$
Spikes$!$
Spikes$!$
Fe#(ppm)#
Sapphire Results:
Burma!
Madagascar!
Sri Lanka!
Kashmir!
Ti#(ppm)#
Fe#(ppm)#
Sapphire Results:
Madagascar!
Kashmir!
Ga#(ppm)#
Sri Lanka!
Ti#(ppm)#
Sapphire Results:
Madagascar(
Madagascar!
Kashmir(
Burma(
Kashmir!
Burma!
Mg#(ppm)#
Thailand (Bo Phloi)
+ Cambodia
Possibilities & Limitations:
Peucat et al (2007)
Comparison
Comparison
Peucat(et(al.(2007(
20.12.2011
80
20.12.2011
Peucat
Peucatetetalal(2007)
(2007)
24.04.2012
24.04.2012
75
Kashmir
Kashmir this
this study
study
Zentraler
ZentralerWeiterbildungskurs
Weiterbildungskurs
SGG
SGG
Kashmir sapphire
30
30
Trace(element(
concentrations(
generally(indicate(
origin(„trends“,(but(
are(often(not(
resulting(in(
conclusive(results.(
The velvety blue of Kashmir sapphires
Photo © H.A. Hänni, SSEF
Sapphires$from$Kashmir$contain$subE
microscopic$inclusions$which$scaher$the$
transmihed$light.$$
$
As$a$result,$these$stones$ogen$show$a$$
highly$appreciated$velvety$blue$colour.$
The(Maharaja(of(Jammu(and(Kashmir,((
circa(1900(
www.kashmirphotos.org/history.html(
Characteristic inclusions in
Kashmir sapphires
Zoning$pahern$
no$ru9le$needles$in$Kashmir$sapphires$!$
Photos: © H.A. Hänni, SSEF
healed$fissure$with$interrupted$fluid$tubes$
Subtle$„dust“$tracks$
Characteristic inclusions in
Kashmir sapphires
Pargasite$needles$(prisma9c)$
Corroded$plagioclase$
ShortEprisma9c$greenish$dravite$(tourmaline)$
Prisma9c$but$corroded$zircons$
The Kashmir - Madagascar challenge !
Kashmir-
Madagascar-
Origin$determina9on$=$combina9on$of$data$
$
$
Blocky$zoning$with$red$VISEfluorescence$
„Parquet“Estructure$
Very$dense$zoning$
Dark-grey-colour-layer-(zone)-
Madagascar-
KashmirOrigin$determina9on$=$combina9on$of$data$
$
$
subtle$„dust“$
flakes$and$
patches$
dense$and$
wellEshaped$
(rhombic)$
„dust“$
patches$
Madagascar-
KashmirOrigin$determina9on$=$combina9on$of$data$
$
$
Fine$and$
partly$
curved$
„dust“$lines$
and$tracks$
Dis9nct$
and$
straight$
„dust“$lines$
Kashmir – Sri Lanka – Madagascar - Basaltic
Usually$$
quite$included$
Characteris9c$$
blocky$zoning$
Ogen$$
rather$pure$
ogen$narrow$
zoning$
Characteris9c$$
Characteris9c$
Inclusions:$
Inclusions:$
E$pargasite$...$ E$apa9te,$diaspore...$
Metamorphic$$
Metamorphic$$
UVEVis$spectrum$ UVEVis$spectrum$
Low$Fe$
Low$Fe3+$
Low$Fe$
Slightly$higher$Fe3+$
Ogen$$
rather$pure$
ogen$narrow$
zoning$with$dark$zones$
Usually$$
included$
Very$regular$$
narrow$zoning$
Ogen$only$$
few$inclusions$
Characteris9c$$
Inclusions:$
E$UEpyrochlore$
Metamorphic$$
UVEVis$spectrum$
Basal9c$
UVEVis$spectrum$
Higher$Fe$
Slightly$higher$Fe3+$
High$Fe$
High$Fe3+$
New source: Fancy sapphires from
Batakundi, Kashmir area (Pakistan)
Sleeping$beauty$?$
New source: Fancy sapphires from
Batakundi, Kashmir area (Pakistan)
Usually$included$(graphite),$milky$and$with$dis9nct$colour$zoning$(Cr).$
Ruby
Burmese ruby
Courtesy of Albion Art collection!
The$ruby$ring$of$Marie$José,$Queen$of$Italy$
Mogok
Gemmarket$in$Mogok$(January$2014)$
Dahaw$mine$:$East$of$Mogok$
Ruby-tes<ng-at-SSEF-
Introduction
Jade,(since(thousand(of(years(
a(mythical(stone(appreciated(
in(Far(East(and(in(the(high(
cultures(of(native(Americans,(
is(currently(again(rising(high(
and(is(sought(after(at(
auctions(in(Hong(Kong(and(
elsewhere.((
The$quest$for$the$perfect$ruby$from$Mogok...$
approx.$14$ct$
Inclusions in Ruby from Mogok
!
!
!
Ru9le$silk$
Twin$lamella$
Calcite$crystals$
Corroded$calcite$crystals$
Photos © H.A. Hänni, SSEF
105$ct$
Generally$included$
Colour$swirls$
Scanning$Electron$microprobe$
www4.nau.edu/microanalysis$
www.vcbio.science.ru.nl$
Titanite$and$plagioclase$inclusion$in$ruby$from$Mogok$
www.op9cs.rochester.edu$
Burmese$Ruby:$approx.$48$cts$
Approx. 48 cts!
„Cut$tongues“$and$geometric$(trigonal)$platelets$
Mong Hsu, Burma
important source of rubies since the 90ies
Many rubies from Mong Hsu have a dark blue core
Mong Hsu, unheated
Dark$blue$to$black$core$zone$(TiEenriched)$
!
Mong Hsu, unheated
Cross$clouds$
Dust$tracks$„comets“$
Mong Hsu, unheated
Zoning$
$
&$healed$fissures$
Carbonates$
LW$UV$reac9on$
Mong Hsu heated
SW$UV$reac9on$
New Ruby Deposit:
Montepuez in
Mozambique
Mozambique (Montepuez)
Rubies$from$Amphibolite$
Montepuez Ruby
Inclusions:$
$
Rounded$crystal$inclusions,$$
ru9le$needles,$twinning$planes,$$
green$amphibole.$
$
E$Inclusions$±$similar$to$Mogok,$Burma$
E$Trace$elements$±$similar$to$Winza
$
Ruby from Winza (Central Tanzania)
Rubies from Winza
Characteris9c$inclusions:$$
E$curved$hollowEchannel$
E$whi9sh$granular$fluid$inclusions$
E$blue$to$greyish$colour$zones$
© H.A. Hänni, SSEF
Colour zoning in corundum from Winza
Vive la France!
New rubies and sapphires
from Madagascar (Didy):
A(ruby(of(25(ct(from(Didy((Madagascar)(showing(an(exceptional(clarity(
The Cinderella job....!
Unheated Burmese rubies mixed
with very few heated ones, or
even synthetic rubies or ruby
imitations (dyed quarzite)!
The colour of ruby
ruby(
Pigeon$blood$red$
$
pink((
sapphire(
purple(
SSEF$defini9on:$
Poe9cal$and$historical$colour$term,$
describing$a$saturated$and$vivid$
crimson$red$colour$of$gemquality$
untreated$rubies$from$Burma$
(Myanmar).$
$
The$SSEF$does$not$apply$this$term$to$
rubies$from$other$sources,$nor$to$
heated$stones.$
$
At$SSEF$$stones$are$compared$to$
colour$charts$and$reference$stones.$
Conclusions:
Origin$of$a$gemstone$should$not$be$misinterpreted$as$a$quality$grade.$
$
Origin$determina9on$is$always$a$expert$opinion$
$
It$is$based$on$a$combina9on$of$me9culous$observa9ons$and$analy9cal$data$
$
New$analy9cal$methods$have$made$and$will$make$important$contribu9ons,$but$due$
to$overlapping$proper9es,$these$data$need$careful$interpreta9on$(no$black$box$!)$
$
S9ll$nowadays,$microscopy$is$a$very$important$and$useful$tool,$as$the$presence,$
shape,$and$distribu9on$of$inclusions$and$zoning$features$are$very$sensi9ve$markers$
of$specific$local$forma9on$processes.$
$
New$deposits$may$be$a$challenge$for$gemmologist,$but$are$welcomed$by$the$trade$to$
answer$the$high$demand$in$gems.$
$
$
Thank you for
your attention
For$more$informa9on,$check$www.ssef.ch$

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