HK June 2012 Kashmir sapphire - SSEF

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  • 1!

    Kashmir sapphires: Potential and limitations of origin determination by chemical fingerprinting with LA ICP mass spectrometry

    Dr.$Michael$S.$Krzemnicki$&$P.$Halicki$Swiss$Gemmological$Institute$SSEF$$Photos$$M.S.$Krzemnicki,$SSEF,$except$where$indicated$otherwise$The$data$presented$in$this$talk$are$the$part$of$the$Master$thesis$of$P.$Halicki,$University$Basel$and$SSEF$

    GAHK$Seminar$23th$June$2012$

    Kashmir Sapphire

  • 2!

    Swiss Gemmological Institute SSEF

    11.01 ct SSEF Gemstone Report No. 63039 Sold for 10740000 HK$ at the Christies sale in HK in May 2012

    Sapphires from Kashmir

    Swiss Gemmological Institute SSEF

  • 3!

    The velvety blue of Kashmir sapphires

    Sapphires$from$Kashmir$contain$subQmicroscopic$inclusions$which$scatter$the$transmitted$light.$$$As$a$result,$these$stones$often$show$a$$highly$appreciated$velvety$blue$colour.$

    Photos H.A. Hnni, SSEF

    Swiss Gemmological Institute SSEF

    Swiss Gemmological Institute SSEF

    In$the$Padar$region$in$the$Zanskar$mountain$range$$

    Treasured by the Maharadja

    The$Maharaja$of$Jammu$and$Kashmir,$circa$1900$www.kashmirphotos.org/history.html$

  • 4!

    Swiss Gemmological Institute SSEF

    from$Tom$D.$LaTouche$(1890)$Records(of(the(Geological(Survey(of(India.$

    The Kashmir sapphire mines

    In$the$Padar$region$in$the$Zanskar$mountain$range:$$Q discovered$1880$Q main$mining$operation$1882Q1887$Q sporadic$activity$between$$1888$$1945$and$up$to$nowadays,$but$no$evident$production$of$

    gemQquality$material$anymore.$

    Origin determination is always an expert opinion

    Swiss Gemmological Institute SSEF

    The$origin$determination$of$gemmological$laboratories$is$always$based$on$scienti`ic$analyses$(trace$element$composition,$absorption$spectra),$inclusion$analyses$(e.g.$Raman$

    microspectrometry$and$FTIR$spectrometry)$and$meticulous$microscopic$observations.$$

    An$origin$of$a$gemstone$mentioned$on$a$gemstone$report$is$always$an$expert$opinion.$

  • 5!

    Foto: Baltoro-Gletscher, Karakorum; Guilhem Vellut via, WikiCommons!

    Coloured gemstones are formed during large-scale geological processes which have shaped the world as we know it today...!

    Kashmir sapphire Foto: Baltoro-Gletscher, Karakorum; Guilhem Vellut via, WikiCommons!

  • 6!

    The collision of the Indian plate with the Eurasian continental plate has produced some of the most important sources for coloured gems, such as the sapphires from Kashmir and the sapphires and rubies from Burma, and many more.!

    Garnier et al. 2006!

    Corundum in skarn!Andranondambo !

    1994"

  • 7!

    Sapphires from East-Africa, Sri Lanka, Madagascar, and South India

    Distribution$of$corundum$deposits$connected$to$PanQAfrican$tectonoQmetamorphic$events$(750Q450$ma)$by$the$collision$of$eastern$and$western$Gondwana.$$In$midQJurassic$(about$160$ma),$India$started$to$drift$towards$north.$

    modi`ied$after$Collins$&$Windley$2002,$Santosh$&$Collins$2003)!

    Swiss Gemmological Institute SSEF

    Tanzania

    Australia

    Kashmir

    Burma (Myanmar)

    Cambodia

    Montana, USA

    Ceylon (Sri Lanka)

    Madagascar

    www.mygeo.info

    Q Kashmir-(India)-Q Burma-(Myanmar)-Q Ceylon-(Sri-Lanka)-Q Madagascar-Q Tanzania-Q Pailin,-Cambodia-Q Australia-Q Montana-(USA)-Q ....-

    Economically important sapphire sources

  • 8!

    Swiss Gemmological Institute SSEF

    Origin determination:

    Combining$classical$approaches$with$advanced$scienti`ic$analytical$methods$

    Lot$3798-A$pair$of$sapphire$and$diamond$ear$clips$by$Cartier$4.70$and$4.60$ct$SSEF$report$62271$$$

    Swiss Gemmological Institute SSEF

    Kashmir Sapphire

  • 9!

    Pargasite$needles$(amphibole)$

    Swiss Gemmological Institute SSEF

    Swiss Gemmological Institute SSEF

    xenomorphous-plagioclase- Short-prismatic-tourmaline-

    corroded-prismatic-zircon- uraninite-with-tension-cracks-Photos H.A. Hnni, SSEF

  • 10!

    Swiss Gemmological Institute SSEF

    `ine$dust$tracks$

    netQlike$healing$`issures$

    Photos H.A. Hnni, SSEF

    Swiss Gemmological Institute SSEF

    CrQenriched$growth$layers$Photo H.A. Hnni, SSEF

  • 11!

    The Kashmir - Madagascar challenge !

    The Kashmir - Madagascar challenge !

    Photos H.A. Hnni, SSEF

  • 12!

    Madagascar sapphire

    Inclusion photos H.A. Hnni, SSEF

    Madagascar sapphire

    Inclusion photos H.A. Hnni, SSEF

  • 13!

    Madagascar sapphire

    Inclusion photos H.A. Hnni, SSEF

    The blurred picture: Sapphire

    SSEF Swiss Gemmological Institute

    Regular$growth$in$basaltic$sapphires$$Overlapping$irregular$growth$(heterogeneous$growth)$

    Photos: H.A. Hnni, SSEF

    The Kashmir Basaltic (e.g. Pailin) mix-up!

  • 14!

    Ceylon sapphire

    SSEF Swiss Gemmological Institute Photos H.A. Hnni, SSEF

    UV-Vis Spectrometry

    SSEF Swiss Gemmological Institute"

  • 15!

    Swiss Gemmological Institute SSEF

    Raman microspectrometry

    Laser Ablation Inductively Coupled Plasma

    Mass Spectrometry LA-ICP-MS

    SSEF Swiss Gemmological Institute

    With Prof. Thomas Pettke !at the Geochemical Lab, !University of Berne, Switzerland!

  • 16!

    Swiss Gemmological Institute SSEF

    The LA-ICP-MS instrument

    The$instrument$at$the$Institute$of$Geological$Sciences,$University$of$Berne$(Switzerland)$has$been$optimized$for$analyses$of$minerals$and$`luid$inclusions$in$minerals.$

    Swiss Gemmological Institute SSEF

    The LA-ICP-MS instrument

    Lambda$Physics,$Coherent:$Pulsed$nanosecond$$ArF$excimer$laser$(193$nm)$

    Microlas$system:$Beam$modulation$optics$to$homogenize$laser$beam$energy$pro`ile$

    Perkin$Elmer:$DRCQe$quadrupole$mass$spectrometer$

    Pettke, 2006!

  • 17!

    Swiss Gemmological Institute SSEF

    Laser ablation

    T. Pettke,, University Berne

    Local$heating$and$vaporization$

    Swiss Gemmological Institute SSEF

    Important: Standardised Operation Procedures

    Q Laser$drill$holes$generally$60Q120$microns$(=0.06Q0.12$mm)$large$and$only$a$few$microns$deep.$Q External$standardisation:$NIST$SRM$610$or$SRM$612$glass$standards$Q Internal$standardisation$for$corundum$usually$99.5$wt%$Al2O3$Q Carrier$gas$helium$admixed$with$hydrogen$for$better$ablation$yield$and$transport$Q To$correct$for$any$possible$instrumental$drift,$each$analytical$series$starts$with$two$analyses$on$

    the$multiQelement$standard$(SRM$610$or$612),$followed$by$maximum$16$analyses$on$the$samples,$and$`inished$with$two$analyses$on$the$standard$again.$

    $$

  • 18!

    Swiss Gemmological Institute SSEF

    Features of LA ICP MS

    +$nearly$all$chemical$elements$can$be$analysed$+$up$to$50$elements$at$the$same$time$+$point$analysis$(zoning)$+$only$minor$sample$preparation$+$large$dynamic$range$of$analysis$$$$$(from$subQppm$to$main$element$concentrations)$+$quantitative$data$

    Q$slightly$destructive$analysis$(laser$drill$holes$diameter$ca$100$m)$Q$how$representative$are$point$analyses$for$the$whole$stone?$Q$raw$data$(qualitative)$has$to$be$processed$to$get$quantitative$data$Q$contamination$effects$Q$spike$`iltering$Q$highly$sophisticated$instrument$$

    Chemical$analysis$of$specimens$

    Photo:$Aeschlimann,$2003$

    Swiss Gemmological Institute SSEF

    Research study with LAICPMS on sapphires

    Photo$$P.$Halicki,$SSEF$

  • 19!

    Swiss Gemmological Institute SSEF

    Data processing

    LA-ICP-MS Pearls

    10

    100

    1000

    10000

    100000

    1000000

    10000000

    100000000

    30 40 50 60 70 80 90 100 110 120

    time (sec.)

    co

    un

    ts

    Mn

    Ca

    I

    Ba

    Mg

    homogeneous$signal$

    Setting$of$integrals$for$data$processing$is$easy$

    Integration time

    Raw data

  • 20!

    Surface$contamination$!$

    Spikes$!$ Spikes$!$Spikes$!$

    Surface$contamination$!$

    Data processing

    Swiss Gemmological Institute SSEF

  • 21!

    Madagascar!

    Kashmir!Sri Lanka!

    Burma!

    Fe-(ppm

    )-

    Ti-(ppm)-

    Results:

    Madagascar!

    Kashmir!

    Sri Lanka!

    Fe-(ppm

    )-

    Ga-(ppm)-

    Results:

  • 22!

    Madagascar$

    Kashmir$

    Burma$

    Madagascar!

    Kashmir!

    Burma!

    Ti-(ppm

    )-

    Mg-(ppm)-

    Results:

    20.12.2011 75

    Swiss Gemmological Institute SSEF

    24.04.2012

    Zentraler Weiterbildungskurs SGG

    30

    Comparison

    Peucat et al (2007) Kashmir this study

    Trace$element$concentrations$generally$indicate$origin$trends,$but$are$often$not$resulting$in$conclusive$results.$

    Possibilities & Limitations:

    24.04.2012

    Zentraler Weiterbildungskurs SGG

    30

    Comparison

    Peucat et al (2007) Kashmir this study

    Peucat$et$al.$2007$20.12.2011 80

    Thailand (Bo Phloi) + Cambodia

    Peucat et al (2007)

  • 23!

    Swiss Gemmological Institute SSEF

    Q LAQICPQMS$is$a$sophisticated$analytical$method$$$$$$$$$to$characterise$the$chemical$composition$of$gemstones.$$Q The$machine$produces$always$results,$but$are$they$real?$$Q Many$instrumental$parameters$have$to$be$controlled$to$produce$reliable$

    results.$$

    Q The$raw$data$has$to$be$carefully$processed$to$$avoid$any$artefact$or$contamination.$

    $Q For$sapphires,$large$overlapping$of$trace$element$concentration$ranges$occur.$$Q Thus,$the$origin$determination$of$sapphires$cannot$r