The Journal of

VolumeGemmolol 26 No. 5 January 1999 y

The Gemmological Association and Gem Testing Laboratory of Great Britain Gemmological Association and Gem Testing Laboratory of Great Britain 27 Greville Street, London EClN 8TN Tel: 01714043334 Fax: 0171 4048843 e-mail: [email protected] Website: www.gagtl.ac.uk/ gagtl President: Professor RA Howie Vice-Presidents: E.M. Bruton, AE. Farn, D.G. Kent, RK. Mitchell Honorary Fellows: RA Howie, RT. Liddicoat Jnr, K. Nassau Honorary Life Members: D.J. Callaghan, E.A Jobbins, H. Tillander Council of Management: C.R Cavey, T.J. Davidson, N.W. Deeks, RR Harding, M.J. O'Donoghue, I. Thomson, Y.P. Watson Members' Council: AJ. Allnutt, P. Dwyer-Hickey, S.A Everitt, R Fuller, A.G. Good, J. Greatwood, B. Jackson, J. Kessler, J. Monnickendam, L. Music, J.B. Nelson, P.G. Read, R Shepherd, P.J. Wates, C.H. Winter Branch Chairmen: Midlands - G.M. Green, North West -I. Knight, Scottish - B. Jackson Examiners: AJ. Allnutt, M.5c., Ph.D., FGA, L. Bartlett, B.5c., M.Phil., FGA, DGA, E.M. Bruton, FGA, DGA, C.R Cavey, FGA, S. Coelho, B.5c., FGA, DGA, Prof. AT. Collins, B.5c., Ph.D, AG. Good, FGA, DGA, G.M. Howe, FGA, DGA, G.H. Jones, B.5c., Ph.D., FGA, M. Newton, B.5c., D.Phil., CJ.E. Oldershaw, B.5c. (Hons), FGA, B.L. Plumb, B.5c., FGA, DGA, RD. Ross, B.5c., FGA, DGA, P.A Sadler, B.5c., FGA, DGA, E. Stern, FGA, DGA, S.M. Stocklmayer, B.Sc. (Hons), FGA, Prof. I. Sunagawa, D.5c., M. Tilley, GG, FGA, CM. Woodward, B.5c., FGA, DGA The Journal of Gemmology Editor: Dr RR Barding Assistant Editors: M.J. O'Donoghue, P.G. Read Associate Editors: Dr CE.s. Arps (Leiden), G. Bosshart (Zurich), Prof. AT. Collins (London), Dr J.W. Harris (Glasgow), Prof. RA Howie (Derbyshire), Dr J.M. Ogden (Cambridge), Prof. AB. Rankin (Kingston upon Thames), Dr J.E. Shigley (Carlsbad), Prof. D.C Smith (Paris), E. Stern (London), S.M. Stocklmayer (Perth), Prof. I. Sunagawa (Tokyo), Dr M. Superchi (Milan), CM. Woodward (London) Production Editor: M.A Burland

Vol 26, No.5, January 1999 [SSN: 1355-4565 Element mapping of trapiche rubies Dr Karl Schmetzer1, Professor Zhang Beili2, Gao Yan2, Dr Heinz-Jurgen Bernhardt3 and Professor Henry A. Hanni4 1. Marbacher Str. 22b, D-85238 Petershausen, Germany 2. National Gemstone Testing Center, Beijing 100034, RR. China 3. Institutfur Mineralogie, Ruhr-Universitat, D-44780, Bochum, Germany 4. SSEF Swiss Gemmological Institute, CH-4001 Basel, Switzerland

ABSTRACT: Chemical zoning in trapiche rubies was examined by X-ray microfluorescence analysis and by electron microprobe analysis. Two- dimensional element maps indicate a chemical variability of Al, Si, Ca, Ti, Cr and Fe within the samples. This chemical variation is mainly due to primary growth zoning as well as due to carbonate and in places silicate inclusions in orientated channels of the host rubies. Secondary iron staining caused by intense weathering of the samples is also observed.

Keywords: electron probe, element map, ruby, trapiche, X-ray micro- fluorescence

290Q Introduction In the yellow or white arms of the star and in the boundary zones between the core and rapiche rubies from south-east the six trapezohedral ruby sectors, a massive Asia with a fixed six-rayed star, concentration of tube-like inclusions is Tsimilar in effect to trapiche emeralds observed. These inclusions are orientated from Colombia, were recently described by perpendicular to morphologically dominant Schmetzer et al. (1996a). Information dipyramidal crystal faces; they contain available at present indicates that the liquid, two-phase (liquid/gas) and solid trapiche rubies come from Myanmar and fillings identified as magnesium-bearing Vietnam. They consist of six transparent-to- calcite and dolomite by a combination of translucent ruby sectors separated by the electron microprobe analysis and micro- yellow- or white-appearing arms of a Raman spectroscopy. In black or yellow six-rayed star. In some crystals, the six cores, tube-like structures with identical arms (which, unlike typical asteriated fillings also run parallel to the c-axis, i.e. gems, are fixed - that is, they do not move perpendicular to basal faces of the trapiche when the stone or light source is moved) rubies. intersect at one small point, forming six Because tube-like structures that extend triangular ruby sectors. In many specimens, into the gem-quality ruby sectors are almost however, the arms extend outward from a colourless, and the calcite and dolomite hexagonal central core, producing six inclusions are iron-free, it was concluded trapezohedral ruby areas. The cores are that the yellow colour of the arms and some usually opaque yellow or black, but cores must be due to intense weathering and transparent red central areas are also secondary iron staining of the cavities and present occasionally. tubes. This interpretation was supported by

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Figure la to f:f: Hexagonal cross-sections of six trapiche rubies, samples A to F; the arms of thethe fixed six-rayed stars intersect in a small centralcentral point (a,b) oror extend extend outward outward from from thethe comers corners of of a a hexagonal blackblack (c,d,e) (cj&je) or orred red (f) (f)core. core. The The arms arms of of the stars are yellowish-whiteyellowish-white (a),(a), yellowyellow (b,c,d,f)(b,c4,f) or zoned yellowish-white in an inner part and yellow c in an outer part of the sample (e). Sizes of the samples are 4.8 mm (a), 3.3 mm (b), 3.2 mm (c), 4.1 mmmm (d),(d), 4.24.2 mm mm (e),(e), and and 4.5 4.5 mm mm x x 5.0 5.0 mm mm (fJ. (f).

Element mapping of trapiche rubiesrubies X-ray fluorescence analyses of selected The application of the two conventional trapiche ruby areas with or without a part of methods described, however, is unable to a yellow arm. provide two-dimensional information about Two methods were applied to determine element concentrations and chemical the chemical properties of trapiche rubies by variability in minerals, which is of great Schmetzer et al. (1996a) providing analytical interest in trapiche rubies. data that represent different-size areas The present paper describes two different within a sample. X-ray fluorescence analysis techniques for the determination of two- reveals an average composition of that part dimensional element maps in trapiche rubies, of the ruby in an area exposed to the X-ray which have been only rarely applied to the beam that can be measured in the range of characterization of gem materials. Using square millimetres. The electron microprobe, trapiche rubies as an example, the techniques on the other hand, is able to analyse much described are able to fill the gap,between smaller areas with diameters down to about conventional X-ray fluorescence analysis and one micrometre. conventional electron microprobe techniques. The chemical variability of a mineralogical sample is, in general, detectable by electron Materials microprobe using two conventional techniques. Preparing X-ray scanning images For the present study six slices of trapiche for selected elements, the intensities of single rubies were cut in a direction perpendicular spots within an image of the area covered by to the c-axis of the corundum crystals. The the electron beam are approximately samples were selected in order to cover the proportional to the concentration of the variability of structural features in trapiche respective elements. A typical example for rubies (see Table I). In detail, samples were trapiche rubies, which was given in the selected with six-rayed stars intersecting at 290Q previous paper, showed the distribution of one small point {Figure la, b) as well as calcium and magnesium in calcite and trapiche rubies with black (Figure lc, d, e) or dolomite as fillings of single orientated tube­ red {Figure If) cores. Parts of the samples like structures and covered an area of revealed sharp yellowish-white (Figure la) or approximately 100 x 100 \xm (0.1 x 0.1 mm). yellow (Figure lb, c) arms, and one sample According to the experimental conditions of showed a colour zoning within the six sharp the instrument, this technique - which is arms of the star with yellowish-white central performed with a fixed, non-moving sample parts and stronger yellow outer parts - is limited to the examination of sectors (Figure le). In one sample, the six yellow which cover a maximum area of about arms of the star widen toward the rim of the 200 x 200 \xm (0.2 x 0.2 mm). crystal (Figure Id), and in one trapiche ruby, Another technique for the evaluation of only thin yellow arms without continuous chemical variability of a sample by electron boundaries to the six trapezohedral ruby microprobe is performed with a moving sectors were observed (Figure If). stage, i.e. a moving sample and a fixed electron beam, in order to prepare various Results scans across the surface of the sample. A typical traverse across a ruby crystal or X-ray microfluorescence (XRMF) analysis another gemstone to show its chemical Chemical zoning was observed in all six variability consists of about 30 to 120 point samples of trapiche rubies examined with the analyses within a scan length in the mm OMICRON XRMF system. Different element range (see Peretti et al, 1995; Schmetzer et ah, concentrations were found for Al, Ca and Fe in 1996b). Using this particular technique, all samples as well as for Si, Ti and Cr in parts information about chemical zoning along of the samples. No chemical inhomogeneities single traverses across a sample is were proven for Mg and V with the obtainable. experimental conditions applied (Table I).

J. Gemm., 1998, 26,5, 289-301 MethodMethodss DataData collection collection proceduresprocedures facilitiefacilitiess availabl availablee o onn ththee microprob microprobee o orr ththee AA well-knowwell-knownn techniqutechniquee toto displadisplayy maximumaximumm numbenumberr ooff energenergyy regionregionss two-dimensionatwo-dimensionall element element distribution distributionss o fof alloweallowedd b byy ththee ED EDSS softwaresoftware.. samplsamplee area areass i sis t oto sca scann th thee electro electronn bea beamm o off UsinUsingg WDWDSS systemssystems,, ththee analyseanalysedd anan electro electronn microprob microprobee (o (orr o off a a scanninscanningg samplesample,, ththee diffractindiffractingg crystacrystall anandd ththee electroelectronn microscopemicroscope)) anandd toto colleccollectt ththee detectodetectorr musmustt bbee oonn ononee circlcirclee (Figure(Figure 2a).2a). signalsignalss foforr imagimagee developmendevelopmentt usinusingg aa AccordinAccordingg toto thesthesee opticaopticall anandd geometricageometricall wavelengtwavelengthh dispersivdispersivee spectrometespectrometerr conditionsconditions,, onl onlyy smal smalll area areass ooff a a samplsamplee ca cann (WDS)CWDS), ,whic whichh ha hass bee beenn se sett t oto th thee positio positionn bbee examineexaminedd witwithh aa fixedfixed samplsamplee stagestage.. ofof th thee require requiredd characteristicharacteristicc X-radiationX-radiation.. BecausBecausee itit iiss nonott possiblpossiblee ttoo scascann aann X-raX-rayy AnotheAnotherr possibilit possibilityy i sis toto ususee ththee signalsignalss o off beambeam,, X-ra X-rayy fluorescence fluorescencetechnique teclmiquess cannocannott a aselecte selectedd rang rangee o off channel chalmelss o off a ann energenergyy bbee used used foforr thi thiss kin kindd o off imagin imagingg procedure procedure.. dispersivdispersivee spectromete spectrometerr (EDS (EDS)) representinrepresentingg IInn ordeorderr ttoo overcomovercomee ththee problemproblemss ththee requesterequestedd radiationradiation. . ThThee signalsignalss ar aree mentionedmentioned,, aa differendifferentt kinkindd ooff imagimagee displayedisplayedd i nin rea reall tim timee o onn a a scree screenn whic whichh i sis generatiogenerationn cacann bbee appliedapplied. . FoForr thesthesee synchronizesynchronizedd wit withh th thee scannin scanningg syste systemm o off techniquetechniquess th thee electro electronn bea beamm oorr a a stronglstronglyy ththee microprobe microprobe.. In In moder modernn systems systems,, thes thesee collimatecollimatedd beabeamm ooff primarprimaryy X-rayX-rayss ooff aa signalsignasls ma mayy b ebe store storedd an andd accumulate accumulatedd i nin microfluorescencmicrofluorescencee system system remainremainss fixefixedd aatt ordeorderr to to displa displayy th thee complet completee image image.. In In th thee ononee positiopositionn anandd ththee samplsamplee witwithh ititss lattelatterr cas casee th thee signalsignalss ooff mormoree thathann on onee samplsamplee stag stagee isis movemovedd iinn twtwoo orthogonaorthogonall elementelement ca cann bbee acquireacquiredd simultaneouslysimultaneously.. directiondirectionss undeunderr ththee fixedfixed beabeamm coverincoveringg LimitinLimitingg factor factorss araree ththee numbe numberr o off WD WDSS ththee samplsamplee areareaa ooff interestinterest.. IInn thesthesee 293 Figure 2a: Schematic drawing of the experimental conditions il1 the electron microprobe for 293 Figureelement 2a: mappin Schematicg of larger drawing areas s hoofw theing experimentalthe incident el ectronconditions beam, thine movingthe electron sampl emicroprobe stage, the for elementfixed diffra mappingcting cry of slargertal and areas the X showing-ray detec thetor ;incident the diffracting electron cry beam,stal and the th mooinge detector sample form astage, the fixedwave diffractinglength disp ecrystalrsive sp eandctrom theete X-rayr (WDS). detector; the diffracting crystal and the detector form a wavelength dispersive spectrometer (WDS).

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Figure 2b, c: Data collection for element mapping by XRMF and EMPA in a step-by-step (b) or m Figurecontinuous 2b, c: raster Data modecollection (c); the for analyticalelement mapping details of by Figur XRMFe 2b and repres EMPAent the in adata step~by-step collection (b)for ora continuoustrapiche ruby raster by electronmode (c); microprobe the analytical with detailsa step-by-step of figure measuring 2b represent distanc thee dataof about collection 10 flm forand a trapichea beam diameter ruby by ofelectron approximately microprobe 3 Fm; with the a analytical step-by-step details measuring of Figure distance 2c represent of about data 10 collection pm and afor beam a trapiche diameter rubl) of approximately by electron microprobe 3 pm; the inanalytical a continuous details raster of Figure mode 2c with represent a beam data diameter collection of forapproximately a trapiche ruby 3 flm by and electron a line microprobelength of about in a 6continuous flm ; analysed raster areas mode are withhatched a beam, arrows diameter indicate of approximatelythe direction of 3 thepm moving and a line stage. length For elementof about mapping 6 pm; analysed by XRMF areas analysis are hatched, an X-ray arrows beam indicatewith a thediameter direction of 70of 11mthe movingwas used stage. in a continuousFor element raster mapping mode, by i.e. XRMF overlapping analysis areas an X-ray within beam the sample with a diameterwere measured of 70 pm several was usedtimes in. a continuous raster mode, ie. overlapping areas within the sample were measured several times.

J. Gemm., 1998,1998,26,5,289-301 26, 5, 289-301 systems, in addition to the elements to be its original position on the sample surface. analysesystems,d anin daddition the sampl to ethe area elements, the use rto ha bes itsThus original, an enlarge positiond imagon thee osamplef the sampl surface.e is alsanalysedo to selec andt th thee desire sampled resolution area, the user, i.e. hasthe Thus,produce and enlargedrepresentin imageg th eof elemen the samplet compo is­ numbealso to rselect of dat thea desiredpoints resolution,on the analyse i.e. thed producedsition of onrepresentinge element thein thelemente sample compo­. The samplnumbere ofare adata whic pointsh for onm thea analysedregular, sitionimage sof ca onen b eelement treated inmathematically the sample. ,The e.g. images can be treated mathematically, e.g. rectangulasample arear gri dwhich on th eform sampl ae regular,surface. intensity relations between two elements intensity relations between two elements Eacrectangularh point ogridf suc hon a thegri dsample represent surface.s one may be computed and depicted. The Each point of such a grid represents one may be computed and depicted. The pixel in the later X-ray image. element distribution can be stored and pixel in the later X-ray image. element distribution can be stored and Furthermore, the counting time for each printed depending on the capabilities of Furthermore, the counting time for each printed depending on the capabilities of measuring point has to be selected. Ttoo the computer programme in use. measuring point has to be selected. Two the computer programme in use. slightly different data collection slightly different data collection procedures are possible: procedures are possible: Element mapping using X-rayX-ray (a(a)) IInn a non-continuounon-continuouss analysisanalysis modemode microfluorescence analysis analysis (XRMF) (XRMF) (Figure(Figure 2b)2b) the th esample sampl e isi smoved moved tot oa a Element mapping by XRMF was point of the rectangular grid and then Element mapping by XRMF was point of the rectangular grid and then developeddeveloped inin thethe mid-'eightiesmid-'eighties byby severalseveral ththee countincountingg timtimee iiss started.started. ThThee working groups in Japan and in the United measured intensity signal of the working groups in Japan and in the United measured intensity signal of the StatesStates (Kobayashi(Kobayashi et al.al,, 1985;1985; NicholsNichols andand fluorescencfluorescencee radiatioradiationn representrepresentss ththee Ryon, 1986; Wherry and Cross, 1986). A element concentration of the currently Ryon, 1986; Wherry and Cross, 1986). A element concentration of the currently commerciallycommercially availableavailable analysisanalysis systemsystem exciteexcitedd samplsamplee volumvolumee whicwhichh mainlmainlyy was designed by Kevex Instruments and depends on the beam diameter. On was designed by Kevex Instruments and depends on the beam diameter. On marketemarketedd withwith thethe tradetrade namename OMICROOMICRON .. completiocompletionn ooff ththee selecteselectedd countincountingg The OMICRON system and similar time, the measuring procedure is The OMICRON system and similar time, the measuring procedure is facilitiesfacilities werewere appliedapplied forfor elementelement stopped and the sample is moved to the stopped and the sample is moved to the mappingmapping ofof metals,metals, alloys,alloys, rocksrocks andand next point of the grid. This is a step-by- next point of the grid. This is a step-by­ minerals,minerals, butbut alsoalso forfor organicorganic matter,matter, e.g.e.g. 295 step procedure. step procedure. leavesleaves,, tissuetissuess andand bonesbones (Boehme,(Boehme, 1987;1987; (b)I(b)Inn aa continuoucontinuouss analysianalysiss modmodee Nicholicholss et al.A.,, 1987;1987; Cross Cross and and Wherry, Wherry ,1988; 1988 ; (Figure(Figure 2c) 2c) along along theth emovement movemen tof o fthe th e WhenWherryy andand Cross,Cross, 1988;1988; CarpenterCarpenter etet aI.,al, samplsamplee betweebetweenn twtwoo grigridd pointspoints,, ththee 1989;1989; CarpenterCarpenter andand Taylor,Taylor, 1991;1991; intensitintensityy ooff ththee specifiespecifiedd characteristicharacteristicc KobayashiKobayashi et aI.,ah, 1991;1991; CrossCross etet aI.,al, 1992;1992; X-radiatioX-radiationn iiss continuouslcontinuouslyy measuremeasuredd RindbyRindby et al.,al, 1992;1992; VoglisVoglis et aI.,al, 1993;1993; bbyy ththee detectordetector.. ThThee resultinresultingg intensitiesintensities CarpenteCarpenterr et al.al,, 1995a,b).. XRMFXRMF waswas represenrepresentt ththee averagaveragee elemenelementt comparecomparedd byby PozsgaiPozsgai (1991)(1991) withwith similarsimilar concentrationconcentrationss ooff ththee exciteexcitedd samplsamplee techniquestechniques,, e.ge.g.. X-rayX-ray fluorescencefluorescence inin thethe volumvolumee betweebetweenn ththee twtwoo pointpointss ooff ththee electroelectronn microscopmicroscopee oror X-rayX-ray fluorescencefluorescence rectangularectangularr gridgrid.. ThThee positiopositionn ooff ththee exciteexcitedd bbyy synchrotronsynchrotron radiation.radiation. datdataa poinpointt iinn ththee pbcel-by-pixepixel-by-pixell imagimagee iiss ForFor ththee preparatiopreparationn ofof elementelement imagesimages sesett ttoo ththee middlmiddlee betweebetweenn ththee twtwoo ooff trapichtrapichee rubies,rubies, a conventionalconventional adjacenadjacentt pointpointss ooff ththee grigridd iinn ththee OMICRO N systemsystem (Figure 3) 3 )was wa sused. used . directiodirectionn ooff movementmovement.. ThThee datdataa collectiocollectionn andand handlinghandling ofof thisthis analytical facility was briefly described IInn botbothh modemodess ththee countincountingg resultresultss ooff analytical facility was briefly described by ichols et al. (1987) and a schematic eaceachh poinpointt forfor eaceachh elemenelementt araree storedstored.. by Nichols et al (1987) and a schematic drawing of the OMlCRO analysis SubsequenSubsequentt ttoo ththee completcompletee measurinmeasuringg drawing of the OMICRON analysis procedure of the selected sample area, systesystemm iiss givegivenn bbyy CrosCrosss andand WherryWherry procedure of the selected sample area, (1988). usinusingg speciaspeciall computecomputerr softwarsoftwaree ththee (1988). intensities of each element are linked to a In the analytical facility available for the intensities of each element are linked to a In the analytical facility available for the colour or to a grey scale. Each data point is present study, the diameter of the primary colour or to a grey scale. Each data point is present study, the diameter of the primary classified and plotted on a screen according X-ray beam could be varied between classified and plotted on a screen according X-ray beam could be varied between to a corresponding colour with respect to 50 and 2000 I!m. However, the best spatial to a corresponding colour with respect to 50 and 2000 um. However, the best spatial

ElementElement mappingmapping ofof trapichetrapiche rubies ElementElement mapping mapping usingusing electron electron microprobeitikroprxfoe analysis analysis (EMPA) (EMPA) TheThe datadata acquisitionacquisition procedureprocedure byby electronelectron microprobemicroprobe isis similarsimilar toto thattha t ofof XRMF.XS3MR AsAs WDSWDS facilitiesfacilitie s (see(se eFigure Figure 2n) 2a) havehave muchmuch betterbetter wavelengthwavelength resolutionresolution thanthan EDS EDS systems systems and and better bette rpeak-to-back­ peak-to-back­ groundground ratios,ratios , WDSWD S imagesimages arear e muchmuch clearer thanthan EDSEDS images.images . Thus,Thus , datadata collection by WDSWE6 systems systems is is preferred preferred for for elementelement mappingmapping byby electronelectron microprobe.microprobe . t^m3;mFigure 3: The OmCRmOMICRON XRMXRMFF analysis AccordingAccording toto thethe numbernumber of of WDSWDS facilities facilitie s systemsystem consisting ofof the the basic basic measurement measurement availableavailabl e inin thethe analyticalanalytica l systemsystem ofof aa unitIlIIit (right)(right) colourcolour TV TV sample sample display display (centre) (c microprobemicroprobe (up(up toto fivefive spectrometersspectrometers inin alld computer-based data processor (left). modernmodern instruments),instruments), thethe numbernumber ofof elementselements whichwhich cancan bebe mappedmapped Simultaneouslysimultaneously isis Limitedlimited toto five.five. ForFor resolution and intensity versus resolution and intensity Versus mappingmapping ofof additionaladditional elements,elements ,the the run run is i s backgrounbackgroundd conditionconditionss werweree obtaineobtainedd iinn repeated with new spectrometer ettings. vacuum with a collimator diameter of repeated with new spectrometer settings. vacuum with a collimator diameter of FromFrom experienceexperience itit waswas foundfound thatthat 70Jim70 ~tm.. ThThee examinatioexaminationn ooff ththee sisixx expressive images should consist of at least trapiche ruby samples of about 3 to 5 mm expressive images should consist of at least trapiche rufay samples of about 3 to i5 mm 3030 000000 pixelspixels representingrepresenting singlesingle pointspoints inin iinn sizsizee wawass performeperformedd iinn a continuouscontinuous the rectangular grid. This corresponds to raster mode (see Figure 2c) with 250 the rectangular grid. This corresponds to mm^ t^e (see Figure 2c) with 250 aboutabout 1212 hourshours of of acquisition acquisition time time with, with ,for fo r analyticaanalyticall datdataa collectiocollectionn stepssteps alongalong both both example, one second counting time for 296 X and Y directions of the sample stage. example, one second counting time for •&'-. X and Y directions of the sample stage. eacheach analyticalanalytical pointpoint (plus(plus processing processing time, time , ConsequentlConsequently,y a singlsinglee X-raX-rayy imagimagee ooff plus time for moving the sample stage if one sample contains information from plus time for moving the sample stage if one sample contains information! from datadata collectioncollection inin aa non-continuousnon-continuous rasterraster 625062 5000 singlsinglee grigridd pointspoints.. WitWithh a beabeamm mode is applied). Consequently, this diameter of 70 ~tm, each grid point repre­ mode is applied). Consequently, this ? :& 70 fiin, each grid point Wre* techniquteclutiquee isis timetime consumingconsuming andand requiresrequires sents an area of ruby and' [a.pc^^teptogB a possible range ' an extremely stable microprobe system of inclusions in that area. The energy ail extremely stable microprobe system inclusions in that area, the m^gy' (Bernhardt et al., 1995). dispersive X-ray fluorescence spectra (Bernhardt et at, 1995). disj^iye Xryay fluorescence speptra For the evaluation of this technique to obtained during the continuous For th^ evaluation of this technique to '^^0^^^\^i^ ' ;tfte/ ;cant^cto; gemmological problems element maps movement were collected with a Si (Li) movement were collected with a 'St (E9 gemmoiogical problems dement maps detector. The required measuring time were performed for one trapiche ruby *;"..')The required measuring wer(samplee performe C, Figured foIe)r onin eboth trapich analyticale ruby was about two to three hours. As the timdatae (samplmodes e mentionedC, Figure 1c)above, in boti.e.h analyticain non­ l collection was repea ted up to four times modes mentioned above, i.e. in non- «||ferti(# was repeated up to four continuous and continuous raster modes. for each ruby sample, the examinationtiftes of: contmuous and continuous raster modes. one trapiche ruby wasth carriede examinatio out overn o 8f A first run was done with a CAMECA to 12 hours. The collected data were Camebax\\ >A^ first electrontu n .*MB donmicroprobee wffiba forCAMECA three mm, Camebax electron microprobe for three processed by image-forming software to elements, AI, Ca and Fe. Data were complex two-dimensional element collected step by step along a rectangular images consisting of 62 500 pixels each. grid with point distances of 10 ~ during Element maps were prepared for eight an analysis time of 1 second at each of the elements, namely Mg, Al, Si, Ca, Ti, V, Cr 90000 analysis points1 secon (see dFigure at eac 2b).h o fFor the and Fe (the OMICRON system allows the this measurement,$M** an& analysis'$$£ 'Pj0i?e-2&>. time of 35 -Fo r simultaneous acquisition of up to 25 hours was needed. an analysis time of 35 element maps from one set of analytical A second run was performed with a data). CAMECA Camebaxrun was performeSX50 delectron with a $*§), <2aii^t*ax: $%88 electron

/f.. Gemm., 1998,1998,26,5,289-301 26, 5, 289-301 microprobmicroprobee facilit facilityy fo forr Al AI,, SiSi,, CCaa anandd Fe Fe.. writtewrittenn b byy on onee o off th thee author authorss (H.-J.B.(H.-J.B.)) wawass UsinUsingg ththee foufourr wavelengtwavelengthh dispersivdispersivee appliedapplied. . spectrometerspectrometerss ofof ththee microprobemicroprobe,, datdataa werweree collecte collectedd i nin continuou continuouss raste rasterr mod modee CharacterizationCharacterization of inclusions along a scan line of approximately 6 jxrn for along a scan line of approximately 6 lAm for ThThee examinatio examinationn ooff th thee sisixx trapichtrapichee rubiesrubies 515122 length lengthss alon alongg th thee X X an andd foforr 515122 lengthlengthss bbyy X-raX-rayy microfluorescencmicrofluorescencee analysianalysiss alonalongg ththee YY directiodirectionn ooff ththee samplsamplee revealerevealedd extraordinaril extraordinarilyy hig highh concentration concentrationss (Figure(Figure 2c).2c). ConsequentlyConsequently,, ththee elementelement ooff Si Si,, Han 11 andd F Fee iinn ththee sisixx armsarms ofof thethe samples samples imageimagess consis consistt o fof 26214 2621444 pixel pixelss each each. .Dat Dataa CC anandd DD.. FoForr ththee characterizatiocharacterizationn ooff incluinclu­­ collectiocollectionn wa wass performe performedd durin duringg a a perio periodd sionsionss i nin th thee orientate orientatedd channel cl1anneiss o off thes thesee twtwoo ofof 0.0.22 secondsecondss alonalongg eaceachh measurinmeasuringg trapichtrapichee rubie rubiess (i(inn additioadditionn ttoo ththee previouslypreviously distancdistancee o fof abou aboutt 6 6 f-im ~un,, an andd approximatel approximatelyy identifieidentifiedd calcitcalcitee anandd dolomitdolomitee fillings)fillings),, 1515 hour hourss wer weree needeneededd foforr ththee completcompletee severaseverall channelchannelss inin botbothh samplesampless werweree measuremenmeasurementt procedur proceduree foforr mappinmappingg ooff analyseanalysedd bbyy electroelectronn microprobmicroprobee usinusingg ththee fou fourr element elementss mentioned mentioned.. conventionaconventionall energenergyy dispersivdispersivee anandd wavewave­­ FoForr imagimagee formationformation,, speciaspeciall datdataa lengtlengthh dispersivdispersivee systemsystemss ooff aa CAMECCAMECAA handlinhandlingg anandd image-forminimage-formingg softwarsoftwaree CamebaCamebaxx SX5 SXSO0 electroelectronn microprobemicroprobe..

ThThee imagimagee processingprocessing softwaresoftware ooff thethe yellowish-whityellowish-whitee armarmss ooff ththee starsstars aass welwelll asas inin analyticaanalyticall systemsystem generategeneratess elementelement imagesimages ththee blacblackk corecoress ooff samplessamples CC,, D andand E ooff ththee samples,samples, iinn whichwhich a coloucolourr codecode iiss comparedcompared ttoo thethe aluminiualuminiumm concentrationconcentration ooff usedused forfor varyinvaryingg concentrationconcentrationss betweenbetween ththee sixsix triangulatriangularr oorr trapezohedratrapezohedrall rubyruby differendifferentt analysianalysiss points.points. VariableVariable elementelement sectors.sectors. ThisThis wawass alsoalso observedobserved foforr chromiumchromium 297 concentrationconcentrationss areare displayedisplayedd pixepixell byby pixelpixel inin iinn thethe yellowish-whityellowish-whitee armarmss ofof samplesample A 297 ththee X-raX-rayy imageimage iinn ththee sequencesequence (from(from lowlow toto (Figure 5) 5) and and in in the th eblack black cores core sof o fsamples sample sC C highighh concentrations)concentrations) violeviolett ~-> blubluee -~> greengreen andand EE.. ThThee redred corcoree ooff samplesample FF,, oonn ththee otherother hand, revealed a higher chromium concentra­ ~-> yellowyellow ~-> redred andand examplesexamples ofof CaCa andand FeFe hand, revealed a higher chromium concentra­ areare shownshown iinn Figure 4a, 4a, b. b. tiotionn thathann thethe sixsix trapezohedraltrapezohedral rubrubyy sectorssectors ooff ththee sample.sample. IInn fourfour trapichetrapiche rubiesrubies,, a distinctdistinct ElementElement distributiodistributionn mapmapss ofof samplessamples A,A, B chromiumchromium zoninzoningg withiwithinn ththee sisixx triangulartriangular andand D areare presentedpresented inin Figures 5 5to to 7. 7 .In In all al l (samples(samples A andand BB;; FigureFigure 6) 6 )or o rthe th esix si xtrapezo­ trapezo­ samples,samples, wwee observeobservedd a distinctldistinctlyy smallersmaller hedrahedrall rubrubyy sectorssectors (sample(sampless E anandd F)F) waswas aluminiumaluminium concentratioconcentrationn inin thethe yellowyellow oror alsoalso observed.observed.

Figure 4a, la, b:b: ElementElement maps maps of ofCa Ca (left) (left) and andFe (right) Fe (right) for trapiche for trapiche ruby, sample ruby, C,sample obtained C, byobtained XRMF by XRMF analysis. DifferentDifferent element element concentrations concentrations are displayed are displayed pixel by pixelpixel byin thepixel XRMF in the map; XRMF increasing map; increasing concentrations are are colour colour coded coded in the in sequence the sequence violet -+violet blue --+> bluegreen - >-+ green yellow - >-+ yellow red. -> red.

Element mapping of trapiche rubiesrubies Figure 5: Element Figure 5: Element distribution maps for distribution maps for trapiche ruby, sample A, trapiche ruby, sample A, obtained by XRMF obtained by XRMF analysis; the six analysis; the six yellowish-white arms of yellowish-white arms of the sample intersect at the sample intersect at one small central point. one small central point.

298

Figure 6: Element Figure 6: Element distribution maps for distribution maps for trapiche ruby, sample B, trapiche ruby, sample B, obtained by XRMF obtained by XRMF analysis; the six yellow analysis; the six yellow arms of the sample inter­ arms of the sample inter­ sect at one small central sect at one small central point. point.

Figure 7: Element Figure 7: Element distribution maps for distribution maps for trapiche ruby, sample D, trapiche ruby, sample D, obtained by XRMF obtained by XRMF analysis; the six broad analysis; the six broad yellow arms of the yellow arms of the sample extend outward sample extend outward from a hexagonal black from a hexagonal black core. core.

J. Gemm., 1998,26,5,289-301 ]. Gemm., 1998, 26, 5, 289-301 Figure 8: Element maps ofofAl, AI, Si, Ca andand FeFefor for trapichetrapiche ruby,ruby, samplesample C, C, obtained obtained by by EMPA.EMPA. DifferentDifferent element concentrations are displayed pixel by pixel in the XRMF map; increasing concentrations are colour coded inin thethe sequencesequence violetviolet -+-* blueblue -+-> greengreen -+-> yellowyellow -+-*• red;red; (a) (a) two two element element maps maps for for Ca Ca are are given, which were obtained fromfrom datadata collectedcollected in in a a step-by-step step-by-step measuring measuring mode, mode, different different colour colour codes codes are applied for image forming according to the counting rates measured at each analysis point; (b) fourfour elementelement mapsmaps forfor AI,Al, Si,Si, CaCa andand FeFe werewere obtainedobtained fromfrom aa continuouscontinuous rasterraster mode.mode.

299 299

Element mapping of trapiche rubiesrubies VariousVarious calciumcalcium concentrationsconcentrations duedue toto corescores ofof thethe samples. Semi-quantitativeSemi-quantitative andand inclusionsinclusions ofof calcitecalcite andand dolomitedolomite (see(see quantitativequantitative chemicalchemical examinationexamination ofof severalseveral SchmetzerSchmetzer et al.al.,, 1996a)1996a) werewere foundfound inin thethe inclusionsinclusions withinwithin thesethese zoneszones werewere performedperformed yellowish-whiteyellowish-white oror yellowyellow armsarms ofof allall sixsix byby single-pointsingle-point analysesanalyses usingusing thethe energyenergy samplessamples andand inin thethe blackblack corescores ofof samplessamples C,C, D dispersivedispersive andand wavelengthwavelength disperSivedispersive analyt­analyt­ andand E.E. AnyAny variationvariation ofof magnesiummagnesium concentra­concentra­ icalical systemssystems ofof thethe microprobe.microprobe. TheseThese analysesanalyses tiontion causedcaused byby thethe dolomitedolomite inclusions,inclusions, onon thethe ofof solidsolid inclusionsinclusions inin orientatedorientated channelschannels otherother hand,hand, waswas notnot resolvedresolved withwith thethe provedproved thethe presencepresence ofof K-AI-K-Al- andand Fe-AI-sili­Fe-Al-sili- measuringmeasuring conditionsconditions used.used. ThisThis resultresult isis catescates withwith oror withoutwithout titaniumtitanium contentscontents inin consistentconsistent withwith decreasingdecreasing sensitivitysensitivity ofof thethe additionaddition toto thethe previouslypreviously identifiedidentified calcitecalcite instrumentinstrument towardstowards lighterlighter elements.elements. andand dolomitedolomite fillingsfillings (see(see alsoalso SchmetzerSchmetzer et alal,., IronIron waswas alsoalso observedobserved inin variousvarious 1996a).1996a). QuantitativeQuantitative chemicalchemical analyses, concentrationsconcentrations inin thethe armsarms ofof thethe six-rayedsix-rayed however,however, gavegave extremelyextremely variablevariable resultsresults andand starsstars asas welwelll asas inin blacblackk cores.cores. InIn general,general, provedproved compositionscompositions ofof thethe silicatessilicates iinn thethe yellowish-whiteyellowish-white armsarms (sample(sample A,A, Figure 5) oror channelschannels toto bebe inhomogeneous.inhomogeneous. FromFrom thesethese yellowish-whiteyellowish-white innerinner partpartss ofof zonedzoned armsarms results,results, itit isis concludedconcluded thatthat thethe channelschannels (sample(sample E)E) revealedrevealed smallersmaller ironiron concentra­concentra­ containcontain severalseveral extremelyextremely fine-grainedfine-grained silicatesilicate tiontionss thathann thethe yelloyelloww outerouter partpartss ofof zonedzoned armsarms minerals.minerals. (sample(sample E)E) oror completelycompletely yellowyellow armsarms (samples(samples B,B, C andand D,D, Figures 6 and 7)7).. NoNo ironiron DiscussionDiscussion wawass foundfound iinn ththee sixsix triangulatriangularr oror trapezohedraltrapezohedral rubyruby sectorssectors ofof allall sixsix samplessamples oror ChemicalChemical zoninzoningg inin trapichtrapichee rubiesrubies hashas inin ththee redred corecore ofof samplesample FF.. beebeenn proveprovedd bbyy elementelement mappingmapping usingusing A somewhatsomewhat unexpecteunexpectedd resultresult wawass thethe XRMFXRMF andand EMPAEMPA techniquestechniques.. ThreeThree observatioobservationn ooff distincdistinctt concentrationconcentrationss ooff siliconsilicon overlappinoverlappingg effecteffectss werweree observeobservedd iinn thethe 300 iinn ththee yellowish-whityellowish-whitee armarmss ooff samplsamplee A samplessamples (Table 1): I): (Figure 5) anandd ooff silicosiliconn anandd titaniutitaniumm iinn thethe (a(a)) ChromiuChromiumm zoninzoningg withiwithinn trigonatrigonall oror yelloyelloww armarmss anandd blacblackk corecoress ooff samplessamples C andand trapezohedratrapezohedrall rubrubyy sectorssectors (sample(sampless AA,, BB,, D (Figure 7).7) . E andand F)F) oror betweenbetween a reredd corecore andand sixsix trapezohedratrapezohedrall rubrubyy sectorssectors (sampl(samplee FF)) isis duduee ttoo growtgrowthh zoninzoningg whicwhichh iiss nonott relatedrelated Electron microprobe analysis (EMPA)(EMPA) ttoo inclusioninclusionss iinn orientateorientatedd channels. ThThee mappinmappingg ooff AlAI,, SiSi,, CCaa anandd FFee iinn samplesample (b(b)) Calcite,Calcite, dolomitedolomite andand K-AI-Fe-Ti-silicateK-Al-Fe-Ti-silicate C bbyy electronelectron microprobemicroprobe (Figures 8a,b) inclusioninclusionss iinn ththee yellowish-whityellowish-whitee toto confirmconfirmss ththee analyticaanalyticall resultresultss obtaineobtainedd byby yelloyelloww armarmss ooff alalll samplesampless anandd iinn thethe XRMFXRMF.. AccordinAccordingg ttoo ththee smallersmaller diametediameterr ooff blacblackk corecoress ooff samplesampless C, D anandd EE,, causecause ththee electroelectronn beabeamm ooff ththee microprobemicroprobe,, a aluminiualuminiumm anandd chromiuchromiumm deficienciesdeficiencies somewhasomewhatt highehigherr resolutioresolutionn iiss obtaineobtainedd forfor anandd variablvariablee concentrationconcentrationss ooff SiSi,, CaCa,, TTii thesthesee elemenelementt mapmapss (compar(comparee Figure lc andand anandd FFee iinn thesthesee areasareas.. Figures 4a,b). IInn botbothh analysianalysiss proceduresprocedures (c) A thirthirdd mechanismechanismm contributincontributingg ttoo thethe appliedapplied,, i.ei.e.. iinn a step-by-stestep-by-stepp (Figure Sa)8a) and and inin chemicachemicall inhomogeneitinhomogeneityy ooff trapichetrapiche a continuoucontinuouss rasterasterr modmodee (Figure Sb),8b), nono signif­signif­ rubies is caused by iron staining of icanicantt differencedifferencess betweebetweenn ththee elemenelementt imagesimages rubies is caused by iron staining of primarprimaryy tube-liktube-likee cavitiecavitiess anandd secondarysecondary werweree observedobserved.. IroIronn contentcontentss werweree observeobservedd iinn irregular fissures due to intense ththee corcoree anandd iinn ththee sisixx armarmss ooff ththee stastarr aass wellwell irregular fissures due to intense weatherinweatheringg ooff mosmostt samples.. A distinctdistinct aass iinn differendifferentt smalsmalll irregulairregularr fissures.. zoninzoningg witwithh intenselintenselyy weathereweatheredd yelloyelloww armarmss iinn ththee outeouterr partpartss anandd leslesss weatheredweathered Characterization of inclusionsinclusions yellowish-whityellowish-whitee armarmss iinn ththee inneinnerr parpartt ooff XRMXRMFF ooff trapichtrapichee rubierubiess C anandd D revealedrevealed samplsamplee E (Figure le)le) iiss correlatecorrelatedd withwith extraordinarilextraordinarilyy highighh concentrationconcentrationss ooff SiSi,, TTii highehigherr iroironn contentcontentss iinn ththee moremore anandd FFee iinn ththee yelloyelloww armarmss anandd iinn ththee blacblackk weathereweatheredd partpartss (Table n.I).

J.J. Gemm.,Gemm., 1998,1998, 26,26, 5,5, 289289-301- 301 IInn summary,summary, elemenelementt mappinmappingg ooff trapichetrapiche CarpenterCarpenter,, D.A,D.A., andand Taylor,Taylor, M.A.,M.A., 1991.1991. Fast,Fast, high­high- rubierubiess revealsreveals a characteristiccharacteristic primaryprimary resolutioresolutionn X-raX-rayy microfluorescencemicrofluorescence imagingimaging.. Advances growtgrowthh zoningzoning,, ththee presencpresencee ofof carbonatecarbonate in X-ray Analysis, 34,34, 217-21217-21 CarpenterCarpenter,, D.A.D.A,, Taylor,Taylor, M.A.M.A,, anandd HolcombeHolcombe,, CE.,C.E., 19891989.. anandd somesome silicatsilicatee mineraminerall inclusioninclusionss inin ApplicationApplicationss ooff a laboratorlaboratoryy X-rayX-ray microprobmicroprobee toto orientatedorientated channels,channels, andand secondarysecondary materialsmaterials analysisanalysis.. Advances in X-ray Analysis, 3232,, weatherinweatheringg anandd iron-stainingiron-staining ofof ththee samples.samples. 115-20115-20 Carpenter,Carpenter, D.A.D.A,, TaylorTaylor,, M.A,M.A., andand Lawson,Lawson, RL.,R.L., 1995a.1995a. High-resolutionHigh-resolution X-raX-rayy microfluorescencmicrofluorescencee imagingimaging ConclusionsConclusions witwithh a laboratory-baselaboratory-basedd instrumentinstrument.. Journal of TraceTrace and Microprobe Techniques, 13(2)13(2) 141-61141-61 ElemenElementt mappinmappingg bbyy XRMFXRMF oror EMPEMPAA iiss CrossCross,, B.J.,B.J., LambLamb,, R.D.RD.,, MaMa,, S.,S., anandd PaquePaque,, J.M.,J.M., 1992.1992. aann extremelextremelyy usefuusefull tooltool ttoo understandunderstand Large-areaLarge-area X-raX-rayy microfluorescencmicrofluorescencee imagingimaging ooff variouvariouss effecteffectss ofof chemicachemicall zoninzoningg withinwithin heterogeneousheterogeneous materialsmaterials.. Advances in X-ray Analysis,Analysis, 35,1255-635,1255-644 gegemm materials.materials. PossiblePossible applicationapplicationss ooff CrossCross,, B.J.B.J.,, andand WherryWherry,, D.C.D.C,, 1988.1988. X-raX-rayy micro­micro­ elemenelementt mappinmappingg ttoo gemmologicalgemmological testingtesting fluorescencefluorescence analyseanalyserr forfor multilayermultilayer metalmetal filmsfilms.. Thin problemproblemss areare ththee distinctiondistinction ooff naturanaturall andand Solid Films, 166,166, 263-72263-72 syntheticsynthetic gegemm materialmaterialss duedue ttoo variablevariable KobayashiKobayashi,, YY.,, Fukumoto,Fukumoto, N.N.,, andand KurahashiKurahashi,, M.M.,, 19911991.. chemicalchemical growthgrowth zoninzoningg aass wellwell asas providingproviding X-raX-rayy fluorescencfluorescencee element-mappingelement-mapping spectrometerspectrometer witwithh improvedimproved spatialspatial resolutionresolution.. Measurement Science prooprooff ooff diffusiodiffusionn treatmentstreatments aass recentlyrecently and Technology, 2,2,183^ 183-41 demonstrateddemonstrated bbyy ZhanZhangg et al. (1997).(1997) . KobayashiKobayashi,, YY.,, Kawase,Kawase, A.A.,, UchiumiUchiumi,, A.,A., NakamuraNakamura,, S.,S., DifferentDifferent diameterdiameterss ooff incidentincident X-rayX-ray oorr KubotaKubota,, M.,M., NakataniNakatani,, K.K.,, BanBan,, H.,H., anandd Arai,Arai, T.T.,, 19851985.. ElementElement mappingmapping bbyy X-raX-rayy fluorescencefluorescence spectrometry.spectrometry. electroelectronn beambeamss (70(70 oror 3-A3-4 !-tm\im respectively)respectively) Analytical Sciences, 1,13-171,13-17 werweree applieappliedd toto exciteexcite characteristicharacteristicc X-rayX-ray NicholsNichols,, M.C,M.C., Boehme,Boehme, D.R.D.R,, RyonRyon,, R.W.RW.,, WherryWherry,, D.D.,, fluorescencfluorescencee radiationradiation inin thethe samplessamples andand Cross,Cross, B.B.,, anandd Aden,Aden, G.G.,, 1987.1987. ParameterParameterss affectingaffecting thesthesee givgivee differendifferentt spatialspatial resolutions.resolutions. X-raX-rayy microfluorescencemicrofluorescence (XRMF(XRMF)) analysisanalysis.. Advances in X-ray Analysis, 3030,, 45-5145-51 XRMFXRMF facilitiesfacilities includincludee image-producingimage-producing NicholsNichols,, M.C,M.C., andand Ryon,Ryon, R.WRW.,, 1986.1986. AAnn X-raX-rayy micro­micro­ 301 softwaresoftware packagespackages whicwhichh areare nowadaysnowadays fluorescencfluorescencee analysisanalysis systemsystem withwith diffractiondiffraction routinelroutinelyy availableavailable (e.g.(e.g. ththee OMICRONOMICRON capabilitiescapabilities.. Advances in X-ray Analysis, 29,29,423- 423-66 systemsystem bbyy KevexKevex Instruments).Instruments). TheThe moremore PerettiPeretti,, A,A., Schmetzer,Schmetzer, K.,K., Bernhardt,Bernhardt, H.-J.H.-I.,, anandd Mouawad,Mouawad, F.E,, 1995.1995. RubiesRubies frofromm MonMongg Hsu.Hsu. time-consumintime-consumingg elementelement mappingmapping byby Gems & Gemology, 31(1),31(1), 2-262-26 electronelectron microprobemicroprobe requirerequiress extremelyextremely Pozsgai,Pozsgai, I.,I., 1991.1991. X-raX-rayy microfluorescencmicrofluorescencee analysisanalysis insideinside stablestable instrumentalinstrumental conditionconditionss andand speciallyspecially andand outsidoutsidee ththee electronelectron microscope.microscope. X-rayX-ray developeddeveloped image-processinimage-processingg softwaresoftware Spectrometry, 20(5)20(5),, 215-23215-23 appliedapplied ttoo ththee datadata collection.collection. RindbyRindby,, A.A,, VoglisVoglis,, P.,P., NilssonNilsson,, G.G.,, anandd Stocklassa,Stocklassa, R,R, 19921992.. SoftwareSoftware developmentdevelopment forfor X-raX-rayy microbeammicrobeam spectroscopy.spectroscopy. Advances in X-ray Analysis, 35,35,1247-5 1247-544 Schmetzer,Schmetzer, K.,K., Hanni,Hanni, H.A.H.A.,, Bernhardt,Bernhardt, H.-J.,H.-J., andand AcknowledgemenAcknowledgementt Schwarz,Schwarz, D.,D., 1996a.1996a. TrapichTrapichee rubies.rubies. Gems & Gemology, ThThee authorauthorss araree gratefugratefull ttoo DrDr HH.. FiedlerFiedler 32(4),242-5032(4), 242-50 Schmetzer,Schmetzer, K.K.,, PerettiPeretti,, A.A,, MedenbachMedenbach,, O.0.,, andand ofof GetaGetacc InstrumentebauInstrumentebau,, Mainz,Mainz, Germany,Germany, BernhardtBernhardt,, H.-J.H.-J.,, 1996b.1996b. RussiaRussiann flux-growflux-grownn syntheticsynthetic foforr providinprovidingg informatioinformationn aboutabout thethe alexandrite.alexandrite. Gems & Gemology, 32(3)32(3),, 186-202186-202 OMICRONOMICRON system.system. Voglis,Voglis, P.P.,, Attaelmanan,Attaelmanan, A.A.,, EngstromEngstrom,, P.P.,, LarssonLarsson,, S.,S., andand RindbyRindby,, A,A., 1993.1993. ElemenElementt mappinmappingg ofof bonebone tissuetissuess byby ththee ususee ofof capillarycapillary focusedfocused XRFXRF.. X-ray Spectrometry,Spectrometry, ReferenceReferencess 2222,229-33, 229-33 WherryWherry,, D.D.,, anandd CrossCross,, B.B.,, 1986.1986. XRFXRF,, microbeammicrobeam analysisanalysis BernhardtBernhardt,, H.J.H.J.,, MassonneMassonne,, H.J.H.J.,, Reinecke,Reinecke, TT., Reinhardt,Reinhardt, v anandd digitaldigital imagingimaging combinedcombined intintoo powerfulpowerful newnew I.,J., anandd WillnerWillner,, A,A., 1995.1995. DigitalDigital elementelement distributiondistribution technique. Kevex Analyst, 12,8-9 maps,maps, aann aiaidd foforr petrologicapetrologicall investigations.investigations. Beihefte technique. Kevex Analyst, 12, 8-9 zum European JournalJournal ofof Mineralogy, 7(1),7(1), 2828 Wherry,Wherry, D.D.,, andand CrossCross,, B.J.,B.J., 1988.1988. ApplicationsApplications ooff BoehmeBoehme,, D.R,D.R., 1987.1987. X-rayX-ray microfluorescencmicrofluorescencee ofof geologicgeologic small-areasmall-area X-raX-rayy fluorescencfluorescencee analysisanalysis usinusingg a materials.materials. Advances in X-ray Analysis, 30,3930, 39-- 4444 microbeamicrobeamm X-raX-rayy source.source. Spectroscopy, 3(8),3(8), 38-4038-40 CarpenterCarpenter,, D.A.D.A,, GorinGorin,, A.A,, andand Shor,Shor, J.T.,J.T., 1995b.1995b. AnalysisAnalysis Zhang,Zhang, B.L.,B.L., GaoGao,, YY.,, andand LiLi,, J.Z.,J.Z., 1997.1997. ResearchResearch oonn TTii ofof heterogeneousheterogeneous materialmaterialss witwithh X-raX-rayy microfluores­microfluores­ andand CrCr diffusiondiffusion treatetreatedd stastarr sapphires.sapphires. cenccencee andand microdiffractionmicrodiffraction.. Advances in X-ray Analysis,Analysis, 26th International Gemmological Conference, Abstract 38,557-638,557-622 Volume,5-6Volume, 5-6

Element mapping of trapiche rubiesrubies Identification of B jade by FTIR spectrometer with near-IR fibre-optic probe accessory Gao Yan and Zhang Beili, FGA National Gem Testing Centre, Xisi, Beijing, 100034, P.R. China

ABSTRACT: A FTIR spectrometer with a near-IR fibre-optic probe accessory has been found to be a useful and non-destructive tool for identification of bleached and polymer-impregnated jadeites (so-called B jade). This method has the advantage of application to the testing of not only very thick or mounted stones, but also very large samples such as bracelets, which are difficult to test with other IR techniques. The important features of the technique are use of the fibre-optic probe and measurement of the near-IR frequency range. Therefore, clear near-IR absorption spectra from 7400 cm-1 to 4000 cm-1 could be obtained. The absorptions are caused mainly by the combination of stretching and bending vibrations and the harmonics of stretching vibration of C-H 302 bonds.

Introduction treatment material and another centred at -1 TIR spectrometers have been 3500 cm , caused by the stretching vibration successfully used to identify B jade for of O-H bonds in the host jade. In some many years. The first report was by specimens it is very hard to differentiate the F two groups of peaks. For example, if a Hurwit (1989) when little was known about sample is too thick then a general absorption this kind of jade treatment and its detection. band from 3600-2800 cm-1 may form. When The methods developed to include the this occurs, the absorption peaks in the near-IR widely used FTIR transmission technique frequency range can be measured to (Fritsch et ah, 1992), and the more recent determine the nature of the jade. DRIFT technique (Quek et al, 1997). Although thick or mounted samples can be Because of the low near-IR energy tested using the DRIFT method it cannot be distribution of normally used FTIR used for testing very large samples. instruments and the low molecular The basic principle of the FTIR absorption coefficients of C-H bonds in the transmission and DRIFT techniques to near-IR frequency range, it can be hard to get identify B jade is to study and compare two good signal-to-noise ratio spectra of B jade in groups of absorption peaks, one from the near IR-range. This problem can be 3200 cm"1 to 2800 cm'1, caused mainly by the resolved by use of a near-IR fibre-optic stretching vibration of C-H bonds in the technique.

© Gemmological Association and Gem Testing Laboratory of Great Britain ISSN: 1355-4565 iiss connectedconnected withwith thethe stainless-steelstainless-steel probprobee andand ththee otheotherr endend isis connecteconnectedd witwithh thethe FTIFTIRR spectrometerspectrometer bbyy a specialspecial detectodetectorr (Figure 1). 1). WhiteWhite lighlightt (quartz-halogen)(quartz-halogen) andand a KBKBrr beam­beam­ splittersplitter werweree usedused.. TheThe wavenumberwavenumber rangerange scannedscanned wawass frofromm 65006500 ttoo 42042000 cm-cm-1 withwith a resolutionresolution ofof 8 cm-l;cm-1; thethe scanscan numbernumber waswas 10.10. A samplesample isis exposedexposed toto near-IRnear-IR radiationradiation viavia thethe fibrefibre opticoptic andand mainlymainly diffusediffuse reflectancereflectance lightlight frofromm ththee aggregateaggregate samplesample isis collected.collected. Thus,Thus, a diffusdiffusee reflectancereflectance spectrumspectrum cancan bebe obtaineobtainedd witwithh ththee accessoryaccessory;; forfor thethe principleprinciple ofof Figure 1: 1: TheThe near-IR near-IR fibre-optic fibre-optic probe probe accessory accessory connected to to the the FTIR FTIR spectrometer. spectrometer. diffusediffuse reflectancereflectance,, seesee QuekQuek et al.al. (1997). (1997) . ExceptExcept foforr cleaningcleaning ththee surfacesurface ooff a samplesample witwithh a cleacleann clothcloth,, nnoo samplesample preparationpreparation iiss PrinciplePrinciple andand experimentexperiment necessary.necessary. ThThee samplesample cancan bebe eithereither placedplaced onon PolymersPolymers showshow absorptionabsorption peakpeakss atat aboutabout ththee probprobee mountmount (Figure 2), 2), or o rtouched touched directly directl y -11 withwith thethe probeprobe byby handhand (Figure 3). 3) . 43043000 cmcm- , causecausedd bbyy ththee combinationcombination ooff C-HC-H stretchingstretching andand C-HC-H bendinbendingg vibrationvibrationss andand MoreMore thanthan 5050 piecepiecess ofof A anandd B jadejade thatthat aatt abouaboutt 59005900 cmcm--1 causecausedd bbyy ththee first-gradefirst-grade hahadd beebeenn testedtested bbyy normanormall gemmologicalgemmological multiplmultiplee frequencfrequencyy vibrationvibration ofof C-HC-H methodmethodss anandd bbyy aann FTIRFTIR transmissiontransmission stretching.stretching. spectrometerspectrometer werweree studiedstudied witwithh thethe IInn jadejade,, excepexceptt forfor absorptioabsorptionn aatt 52305230 cm-cm-1 accessory.accessory. FoForr conclusivconclusivee resultsresults,, a roughrough causecausedd bbyy waterwater moleculemoleculess iinn alterationalteration ooff specimespecimenn ooff A jadjadee waswas cutcut intointo twotwo piecespieces by the authors (samples 1 and 2), and sample ththee purpuree jadeitejadeite,, therethere areare nnoo otherother clearclear by the authors (samples 1 and 2), and sample 303 absorptionsabsorptions iinn thethe near-Inear-IRR frequencyfrequency rangerange,, 2 waswas bleachedbleached andand polymer-impregnatedpolymer-impregnated byby thusthus thethe polymepolymerr absorptionabsorptionss inin B jadejade inin thethe a jadejade wholesalewholesale corporation.corporation. near-Inear-IRR rangrangee areare clearclear anandd notnot affectedaffected bbyy ananyy jadeitjadeitee absorption.absorption. ResultsResults andand DiscussionDiscussion ForFor measurementmeasurement a NicoleNicolett Magna-750Magna-750 Figure 4 (a,b)(a,b) showsshows typicaltypical nearnear IIRR FTIFTIRR spectrometerspectrometer anandd a 'sabIR''sablR' fibre-opticfibre-optic spectraspectra ooff twotwo naturalnatural jadeitejadeitess (samples(samples 3 probeprobe accessoraccessoryy werweree used forfor thethe firsfirstt timetime.. TheThe accessoryaccessory consistsconsists ofof integrateintegratedd opticsoptics,, fibre-opticfibre-optic cablecable,, samplingsampling probe,probe, detectordetector andand Figure 3: 3: A A large large sample sample can can be tested be tested by bringing by bringing the probeprobe adjacent adjacent to the to samplethe sample by hand. by hand. probprobee mountmount.. OneOne endend ofof ththee fibre-opticfibre-optic cablcablee

Figure 2: 2: TheThe sample sample can can be testedbe tested by placing by placing it it on the mountmount ofof the the fibre-optic fibre-optic probe. probe.

Identification ofof BB jadejade by by FTIR FTIR spectrometer spectrometer with with near-IR near-IR fibre-optic fil He probe probe accessory accessory 1.80

1.75 a

1.70

1.65

1.60

1.55

1.50

1.45

1.40 2l !:; .n~ I... 1.35 0en .n < 304304 1.30

1.25

1.20 e

1.15

1.10

1.05

1.00

0.95

im 6500 6000 5500 5000 4500 1 Wavenumbers (em- ) Wavenumbers (cor1)

Figure 4: Near-IR spectrum of (a) a high-quality, near-transparent, green natural jadeite (sample 3),3), (b) a poor-quality, opaque, green natural jadeite (sample 4), (c) a bleached andand polymer-impregnatedpolymer-impregnated jadeite, tested using a 'sabIR''sablR' accessory.

J. Gemm., 1998,26,5,302-3071998,26, 5, 302-307 1.160

1.150

1.140

1.130

a 1.120

1.110

1.100

1.090

u~ 1.080 J:: III

-e0

b 1.050

1.040

1.030

1.020

1.010

1.000

0.990

6500 6000 5500 5000 T « 1 4500r- 6500 6000 5500 5000 4500 Wavenumbers (cm-1) Wavenumbers (cm"1)

Figure 5: Near-IR spectrum of (a) A jade before beingbeing bleachedbleached and and polymer polymer impregnated impregnated (sample (sample 1), 1), (b) B jade made from thethe material of samplesample 1 (sample(sample 2), testedtested using a 'sabIR''sablR! accessory.accessory.

Identification of B jade Vyby FTIR spectrometer with near-IR fibre-optic probe accessoryaccessory andand 4)4).. SampleSample 3 iiss a high-quality,high-quality, near­near- spectrumspectrum ofof wax-impregnatedwax-impregnated jadeitjadeitee couldcould transparent,transparent, naturanaturall greegreenn jadeitejadeite.. SampleSample 4 bebe characteristiccharacteristic anandd thatthat identificationidentification ooff isis a poor-qualitypoor-quality,, opaqueopaque,, naturanaturall greengreen wax-impregnatewax-impregnatedd jadeitjadeitee coulcouldd bebe asas easyeasy asas jadeitejadeite.. thathatt ooff polymer-impregnatepolymer-impregnatedd jadeitejadeite.. ItIt cacann bbee seenseen thatthat ththee absorptionabsorption peakpeak -1 occurrinoccurringg atat 52305230 cmcm-I isis thethe characteristiccharacteristic LimitatioLimitationn markmark ooff naturalnatural jadeitejadeite,, bubutt ththee relativerelative intensitieintensitiess ooff ththee absorptioabsorptionn peapeakk may varyvary IfIf a specimenspecimen ofof A jadjadee isis ververyy thithinn andand significantlysignificantly frofromm specimenspecimen toto specimen.specimen. mountedmounted inin jewellerjewelleryy withwith glueglue,, thethe near-IRnear-IR GenerallGenerallyy ththee betterbetter thethe qualityquality ofof a jadeite,jadeite, thethe radiationradiation couldcould penetratepenetrate thethe samplesample andand lowelowerr relativrelativee intensity.intensity. SoSo thethe relativerelative reacreachh thethe organicorganic glueglue layerlayer.. ConsequentlyConsequently a intensitintensityy ofof thethe peapeakk mymy bbee useusedd asas anan spectrumspectrum resemblingresembling thatthat ooff B jadejade couldcould bebe indicatorindicator ofof ththee contentcontent ooff impuritiesimpurities iinn ththee obtaineobtainedd andand bbee misleadingmisleading.. In suchsuch jadeitejadeite,, especiallespeciallyy mineralsminerals thatthat containcontain water.water. instances,instances, thethe measurementsmeasurements musmustt bbee donedone Figure 4 (c)(c) showsshows a typicatypicall near-IRnear-IR carefullcarefullyy withwith thisthis possibilitpossibilityy inin mind.mind. spectrumspectrum ofof a bleachebleachedd andand polymerpolymer impregnatedimpregnated jadeitejadeite.. ThThee representativerepresentative ConclusionConclusionss absorptionabsorptionss includincludee fourfour groupsgroups ofof peakspeaks.. TheThe firsfirstt grougroupp mainlymainly containscontains peakspeaks atat A near-Inear-IRR fibre-opticfibre-optic accessoryaccessory fittedfitted ttoo anan 5985,5922,5985, 5922, 58855885 anandd 57005700 cm"cm-l,1, ththee secondsecond atat IRIR spectrometerspectrometer offerofferss aann effectiveffectivee anandd easyeasy 52305230 cm"cm-l,1, ththee thirthirdd aatt 4680,4680, 46224622 andand methodmethod forfor testingtesting jadjadee iinn variousvarious kindkindss ooff 45345300 cm-cm"I1 anandd ththee fourthfourth aatt 4370,4370, 43443422 andand jewelleryjewellery,, anandd isis particularlparticularlyy applicableapplicable toto 1 43243244 cm"cm-I .. larglargee samples.samples. TheThe sensitivitysensitivity ooff thethe -1 techniqutechniquee iiss goodgood,, anandd cleaclearr andand TheThe firsfirstt grougroupp ooff peakpeakss neanearr 60006000 cm-cm I characteristic spectra can be easily obtained. araree believedbelieved ttoo bebe mainlymainly relaterelatedd toto thethe characteristic spectra can be easily obtained. 306 TheThe followinfollowingg conclusionsconclusions cacann bbee drawn:drawn: absorptioabsorptionn causedcaused bbyy thethe C-HC-H stretchingstretching -1 vibrationvibration,, thethe fourtfourthh groupgroup ofof peakpeakss nearnear 1.1. ExceptExcept forfor aann absorptionabsorption aatt 52305230 em-I,cm , therethere -1 43004300 cmcm--1I toto thethe absorptioabsorptionn ofof botbothh stretchingstretching areare nnoo absorptioabsorptionn peakpeakss betweebetweenn 65006500 cm-cm 1 -1 andand bendinbendingg vibrationsvibrations ofof C-H.C-H. TheThe cause(s)cause(s) andand 50005000 cmcm-I shownshown bbyy naturalnatural jadeitesjadeites.. ofof ththee otheotherr twotwo groupsgroups ooff peakspeaks havehave nonott yeyett 22.. ThThee relativerelative intensitintensityy ooff thethe peakpeak atat beebeenn explained.explained. 52305230 cm-cm-1I cacann bbee useusedd asas aann indicatorindicator ooff Figure 5 5 (a,b) (a,b )shows shows the the spectra spectra ofof sample sample thethe qualityquality ooff a naturalnatural jadeitjadeitee specimenspecimen 1 andand samplesample 2.2. whenwhen comparecomparedd witwithh standardstandard laboratorylaboratory ItIt iiss evidentevident thatthat ththee relativrelativee intensityintensity ooff specimens.specimens. ThThee betterbetter ththee qualityquality ooff thethe ththee peakpeak aatt 52305230 cmcm--1I isis lowerlower afteafterr bleachingbleaching jadeitejadeite,, ththee lowerlower thethe intensityintensity ofof thethe I1 andand polymer-impregnatinpolymer-impregnatingg treatment.treatment. ItIt 52305230 cm"cm- peak.peak. proveprovess directlydirectly thatthat impuritiesimpurities (especially(especially 3.3. InIn jadeitejadeitess examinedexamined afteafterr bleachingbleaching mineralsminerals containingcontaining water)water) cancan bbee destroyeddestroyed treatment,treatment, ththee relativerelative intensitintensityy ofof thethe bbyy bleachingbleaching.. AlthougAlthoughh ththee absorptioabsorptionn peakpeak peapeakk atat 52305230 cm-cm-1I waswas smallersmaller thanthan beforebefore atat 52305230 cm-cm-1I occursoccurs iinn ththee twotwo samples,samples, thethe treatmenttreatment,, soso a relativelyrelatively highhigh peakpeak atat causecausess ofof formationformation areare different.different. 52352300 cmcm--1I cancan bbee aann indicatoindicatorr thathatt thethe jadjadee ThThee spectrumspectrum ofof jadeitjadeitee whicwhichh hashas beenbeen iiss A jadejade.. ThiThiss conclusionconclusion cancan alsoalso bebe waxwax buffebuffedd iiss almostalmost ththee samesame asas thatthat ofof thethe applieappliedd ttoo FTIFERR spectraspectra obtaineobtainedd usingusing a naturanaturall jadeitejadeite,, ththee authorauthorss believbelievee thathatt thethe transmissiotransmissionn technique.technique. contentcontent ofof waxwax inin suchsuch jadeitjadeitee isis tootoo lowlow toto 4.4. TheThe existencexistencee ooff absorptioabsorptionn peakpeakss atat produceproduce significantsignificant absorptionabsorption peakpeakss iinn thethe wavenumberswavenumbers 5985,5985, 5922,5922, 5885,5885, 52305230,, near-IRnear-IR rangerange.. 4680,4622,4680,4622, 4530,4370,4344530, 4370, 43422 anandd 43243244 cm"cm-1I TheThe near-Inear-IRR spectraspectra ofof bleachebleachedd andand waxwax­- indicateindicatess thathatt ththee jadjadee beinbeingg testetestedd hashas impregnatedimpregnated jadeitejadeitess havehave nonott yeyett beenbeen beenbeen bleachebleachedd anandd polymepolymerr impregnated.impregnated. studied,studied, butbut ththee authorauthorss believebelieve thathatt thethe TenTen scanscanss ofof a samplesample areare usuallyusually

/J.. Gemm., 1998, 26, 5, 302-307302-307 sufficientsufficient toto obtaiobtainn a goodgood spectrumspectrum,, ssoo ththee techniquetechnique iiss ververyy suitablesuitable foforr rapidrapid testintestingg ooff largelarge batchebatchess ofof jewelleryjewellery containincontainingg jadejade..

ReferencesReferences Fritsch,Fritsch, E.E., , Wu,Wu, S.S. T.T.T.T.,, MosesMoses,, T.T., , McClureMcClure,, S.F.,S.F., anandd MoonMoon,, M.M., , 1992.1992. IdentificatioIdentificationn ofof bleachedbleached anandd polymer-impregnatepolymer-impregnatedd jadeitejadeite.. Gems && Gemology, Gemology, 28, 28 , 176-87176-87 HurwitHurwit,, K.K., , 1989.1989. GeGemm tradetrade lablab notesnotes:: impregnatedimpregnated jadeitjadeitee jadejade.. Gems & & Gemology, Gemology, 25 (4),25 (4)239-40, 239^1 0 Quek,Quek, P.L.,P.L., andand TanTan,, T.L.,T.L., 1997.1997. IdentificationIdentification ofof B jadejade byby diffusdiffusee reflectancreflectancee infrareinfraredd FourierFourier transfortransformm (DRIFT(DRIFT)) spectroscopy.spectroscopy. Journal of of Gemmology, Gemmology, 25, 25,417-2417-27 7

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Identification of of B Bjade jade by FTIRby FTIR spectrometer spectrometer with near-IR with near-IK fibre-optic fibre-optic probe accessory probe accessory Natrolite from the Bela ophiolite, Pakistan

E. Gnos1, K. Mahmood2, M. Khan2, A.S. Khan2 and Th. Armbruster3 1. Mineralogisch-Petrographisches Institut, Universität Bern, Baltzerstrasse 1,3012 Bern, Switzerland 2. Centre of Excellence in Mineralogy, University of Balochistan, Quetta 3. Laboratorium für Chemische und Mineralogische Kristallographie, Universität Bern, Freiestrasse 3,3012 Bern, Switzerland

ABSTRACT: The zeolite mineral natrolite was found as fracture filling in a slightly boudinaged dolerite dyke in serpentinized harzburgite WSW of Hazarganji, Khuzdar District, SW Pakistan. The mineral occurs as acicular, bundle-shaped aggregates up to 35 cm long and as prismatic milky-white or transparent idiomorphic crystals up to 12 cm long. Unusually large collectors' stones of up to 20.62 ct have been cut from this locality. The shape of idiomorphic crystals and mineral chemistry indicate a structurally highly (Si,Al)-ordered natrolite and this is consis- tent with the low temperature assemblage of associated minerals.

Keywords: Bela ophiolite, natrolite, Pakistan, rodingite, zeolite 308

Introduction charge is balanced mainly by Na situated in the cavities between; H20 molecules also atrolite (ideally Na2Al2Si3O10.2H2O) occupy the cavities. The structure of the is an orthorhombic zeolite mineral natrolite-group zeolites contains a Nwhich is structurally closely related fundamental chain-like unit of edge-shared to mesolite (Na2Ca2Al2Si3O10.8H2O) and tetrahedra oriented parallel to the c-axis scolecite (CaAl2Si3O10.3H2O). The name (Figure 1), This is the reason for the fibrous derives from the Greek natron = soda and morphology common for this mineral group. lithos = stone. Orthorhombic (pseudo- Although natrolite is structurally related to tetragonal) natrolite was first described by mesolite and scolecite, it shows only limited Klaproth (1803). The hardness is 5-5.5 on solid solution with less than 0.5 Ca per unit Mohs' scale, and its specific gravity is cell present in natrolite. Other elements 2.20-2.25. Natrolite is biaxial positive and which may be present in small amounts are refractive indices are a = 1.473-1.480, magnesium and potassium. Small impurities, ß = 1.476-1.486 and y = 1-485-1.496 (Anthony order-disorder effects, and different hydra- et al, 1990). The structure of the mineral was tion stages lead to the structurally, optically solved by Pauling (1930) and Taylor et al. and chemically slightly different minerals of (1933), and recently refined by Artioli et al the natrolite group called gonnardite, tetrana- (1984). The basic structure of natrolite is an trolite, ranite and paranatrolite (Chao, 1980; aluminosilicate framework composed of (Si, Chan and Chao, 1980; Mazzi et alf 1986; Al) tetrahedra. Each oxygen is shared Nawaz, 1988; Krogh Andersen et al, 1969, between two tetrahedra and the negative 1990; Alberti et al, 1995).

© Gemmological Association and Gem Testing Laboratory of Great Britain ISSN: 1355-4565 Quaternary c=:J Miocene flysch .. CJ Paleocene and Figure 1: Basic chain-like orientation of Si, Eocene AI-tetrahedraAl-tetrahedra in natrolite structure, whichwhich explains its its preferred preferred fibrous fibrous growth. grozvth. Bela ophiolite -~ 309 NatroliteNatrolite occurrencesoccurrences areare characteristicallycharacteristically ~ associatedassociated withwith basaltibasalticc rocks,rocks, alkalinealkaline alkaline intrusions,intrusions, basicbasic rocksrocks inin serpentinitesserpentinites andand volcanic rocks salt-lakesalt-lake environmentsenvironments (alkaline(alkaline brines)brines).. InIn ~ basalticbasaltic rocksrocks well-developedwell-developed crystalscrystals formform Cretaceous inin vugsvugs (e.g.(e.g. Hegau,Hegau, Germany;Germany; FaeroeFaeroe and Jurassic Islands;Islands; Auvergne;Auvergne; Bohemia)Bohemia) oror inin associationassociation witwithh hydrothermalhydrothermal alterationalteration (e.g.(e.g. seafloorseafloor metamorphism).metamorphism). NatroliteNatrolite associatedassociated withwith alkalinealkaline intrusionsintrusions is,is, forfor example,example, describeddescribed fromfrom Kola,Kola, USSRUSSR;; Ilimaussaq,Ilimaussaq, Greenland;Greenland; SanSan BenitoBenito County,County, California;California; ththee LangesundsfjordLangesundsfjord inin Norway,Norway, andand thethe KimberleyKimberley diamonddiamond minesmines inin SouthSouth AfricaAfrica.. NatroliteNatrolite associatedassociated withwith basicbasic rocksrocks inin serpentinitesserpentinites isis reportedreported fromfrom thethe BorusBonis Figure 2: 2: OverviewOverview map map of ofthe the Bela Bela ophiolite ophiolite and and MountainsMountains (Judin,(Judin, 1963)1963) andand fromfrom thethe surrounding MesozoicMesozoic and and Tertiary Tertiary rocks. rocks. The The JohnstonJohnston asbestosasbestos minemine inin Quebec,Quebec, CanadaCanada map isis based based on on Jones Jones (1960). (1960). (Poitevin,(Poitevin, 1938).1938). NatrolitNatrolitee formationformation inin associationassociation withwith alkalinealkaline salinesaline brinesbrines isis reportedreported fromfrom Tanzania,Tanzania, andand fromfrom saltsalt lakeslakes RegionalRegional geologygeology inin thethe USAUSA (Hay,(Hay, 1966)1966).. TheThe natrolitesnatrolites ofof thisthis studystudy areare fromfrom Gem-qualityGem-quality natrolitenatrolite isis knownknown fromfrom doleritedolerite dykes,dykes, metasomatizedmetasomatized towardstowards BoundBound Brook,Brook, NewNew JerseyJersey (Dunn,(Dunn, 1976)1976) andand rodingite,rodingite, inin serpentiniteserpentinite ofof thethe BelBelaa MontMont Saint-Hilaire,Saint-Hilaire, QuebecQuebec (Wight,(Wight, 1996)1996).. ophiolite,ophiolite, PakistanPakistan (Figure 2).2). TheThe BelBelaa

Natrolite from the Bela ophiolite,ophiolite, Pakistan Pakistan Figure 3: 3: (a)(a) TypicalTypical outcrop outcrop of ofserpentinized serpentinized harzburgite harzburgite of the of Bela the ophioliteBeta ophiolite (Hazarganji (Hazarganji area) area) containing white-weathering white-weathering folded folded and andboudinaged boudinaged dolerite dolerite dykes. dykes. (b) LongLong prismatic, prismatic, bundle-shaped bundle-shaped aggregate aggregate of natrolite of natrolite associated associated with prismatic with prismatic white natrolite; white sizenatrolite; size 310310 of specimen ca. ca 30. 30 cm. cm. (c) Long prismatic,prismatic, idiomorphic idiomorphic gem-quality gem-quality natrolite natrolite crystals, crystals, up to up12 cmto 12in cmlength, in length,showing showing the the morphology drawn drawn in inFigure Figure 4. 4. (d) CutCut and and faceted faceted natrolites natrolites from from the Be/athe Belaophiolite. ophiolite. Back: left,Back: modified left, modifiedscissors cut, scissors 13.48 ct;cut, centre, 13.48 ct; centre, round brilliant-cut,brilliant-cut, 2.53 2.53 ct; ct;right, right, modified modified scissors scissors cut, 20.62 cut, ct.20.62 Front: ct. Front:left, octagonal left, octagonal cut, 11.26 cut,ct; 11.26 ct; right, rectangularrectangular cut, cut, 5.08 5.08 ct. Allct. Allstones stones are clean.are clean. Photo PhotoB. Schmied. B. Schmied.

ophioliteophiolite iiss a fragmenfragmentt ooff oceaoceann floofloorr andand NearbyNearby,, boudinageboudinagedd doleritedolerite dykesdykes formsforms parpartt ooff ththee westerwesternn ophiolitophiolitee belbeltt ooff metasomatizedmetasomatized towardtowardss rodingiterodingite andand Pakistan whicwhichh waswas obducteobductedd ontoonto ththee edgeedge weatherinweatheringg white,white, containcontain smallsmall («< 1 mm)mm) ofof thethe IndiaIndiann continentalcontinental plateplate duringduring andraditeandradite (demantoid(demantoid)) andand greengreen Palaeocene-EocenPalaeocene-Eocenee timetimess (Allemann,(Allemann, 19791979;; vesuvianitvesuvianitee crystalcrystalss aass coatingscoatings oonn fissures.fissures.

MahmoodMahmood et ah,a/., 1995).1995). ThThee specimensspecimens werewere FibrouFibrouss xonotlite,xonotlite, Ca6 (Si660017)(OH))(OH)2'2, thethe collectecollectedd fromfrom a nearlynearly qlonomineralicmonomineralic crackcrack hydrouhydrouss low-temperaturlow-temperaturee mineraminerall related ttoo filling,filling, upup ttoo 1010 cmcm across,across, iinn a severalseveral metremetre wollastonite,wollastonite, alsalsoo formformss cross-fibrcross-fibree fracturefracture thickthick doleritdoleritee dykdykee WSWWSW ofof HazarganjiHazarganji fillings.fillings. (Figure{Figure 3a). OnlOnlyy calcitcalcitee («< 2 vol.%vol. %)) waswas associated with the natrolite in the crack. associated with the natrolite in the crack. MineralogyMineralogy MostMost ooff thethe natrolitenatrolite occuroccurss iinn ththee formform ooff milky-whitmilky-whitee longlong prismaticprismatic radiatinradiatingg crystalscrystals TheThe natrolitenatrolite frofromm ththee BelBelaa ophioliteophiolite (Figure{Figure 3b) 3b) filling fillin gthe th crackse crack buts bu at fewa few cavities cavitie s formsforms mediumediumm toto lonlongg prismaticprismatic anandd fibrousfibrous containedcontained freely-grownfreely-grown whitwhitee toto transparenttransparent radiatinradiatingg crystalscrystals whicwhichh araree morphologicallymorphologically crystalcrystalss (Figure{Figure 3c) 3c) which whic hallowed allowe da astudy stud yof o f simple,simple, witwithh dominantdominant {ll0}{110} prismprism andand {111}{111} theitheirr morphologymorphology.. TheThe twotwo thickesthickestt purepure pyramidpyramid,, anandd smallersmaller {lOO}{100} prisprismm anandd {101{lOll} crystalcrystalss werewere usedused foforr facetingfaceting anandd thethe pyramipyramidd formsforms (Figure{Figure 4).4). A A fewfew crystalscrystal s resultsresults araree displayeddisplayed inin Figure 3d. 3d. havehave twinnintwinningg onon {llO}.{110}. ThThee samplessamples areare

J./. Gemm., 1998,26,5,308-3121998,26,5,308-312 Table I. I.Electron Electron microprobe microprobe analysis analysisof Bela natrolite of Bela natrolite

, Oil ,, wt.%Wt.% CationsCations on basis of ,, 1010 oxygens Si0Si0 46.5546.55 SiSi 2.9832.983 ---111- --.,),r ------2 2

Ti0Ti02 2 0.080.08 TiTi 0.0010.001

AlAIP203 3 26.7426.74 AlAI 2.0192.019 FeOFeO 0.040.04 FeFe - MnOMilO 0.050.05 MnMil -

CrCr22003 J 0.070.07 CrCr - MgOMgO 0.070.07 MgMg - o.... 8 .... CaOCaO 0.000.00 CaCa - Nap 16.34 Na 2.030 Na20 16.34 Na 2.030 Kp 0.06 K K20 0.06 K - 7.033 TotalTotal 90.0090.00 TotalTota l 7.033

NoteNote:: MeanMean ooff fourfour analysesanalyses.. I\OH20 waswas notnot determineddetermined

anandd thethe totaltotal isis low;low; absorptionabsorption duedue ttoo H200 waswas takentaken intointo accountaccount inin calculatingcalculating ththee oxideoxide percentages.percentages. MicroprobeMicroprobe analysesanalyses werweree performeperformedd onon a CamecaCameca SX-5SX-500 microprobemicroprobe atat BernBern UniversitUniversityy bbyy EE.. Gnos.Gnos. BeamBeam conditionsconditions werweree 1515 kVkV andand 1010 nA,nA ,with with aa defocused defocused beambeam sizesize ofof approximatelyapproximately 3030 micronsmicrons.. NaturaNaturall andand syntheticsynthetic mineralmineralss werweree useusedd aass standards.standards. Figure 4: 4: MorphologyMorphology of ofnatrolite natrolite from from the theBela Bela 311 ophiolite.ophiolite. The The {lID} {110} form form may may be absent; be absent; a second a second givegives s a birefringencbirefringencee ooff 0.000.0055 whicwhichh iiss lowlow pyramidal formform {31I}{311} was observed in somesome anandd probablprobablyy reflectreflectss ththee highighh NNaa andand twinned crystals.crystals. unusuallunusuallyy loloww CaCa,, K anandd MMgg contents.contents. SpindleSpindle stagestage measurementmeasurementss yieldeyieldedd a 2 Vz z colourlescolourlesss anandd shoshoww nnoo fluorescencfluorescencee iinn longlong­- anglanglee ooff 63.36263.362 ± 0.4920.492°°.. TheThe natrolitnatrolitee gemgem oorr short-wavshort-wavee ultravioleultraviolett lightlight,, althoughalthough materiamateriall iiss frefreee ooff inclusioninclusionss anandd neitherneither fluorescencfluorescencee hahass beebeenn describedescribedd foforr samplessamples zoninzoningg nonorr luminescencluminescencee werweree observedobserved frofromm otheotherr localities (e.g(e.g.. LaurentLaurent,, 19411941;; undeunderr ththee cathodcathodee luminescencluminescencee microscope.. AnthonAnthonyy et ah,al., 1990). ThreThreee differendifferentt whitewhite anandd transparentransparentt natrolitnatrolitee crystalcrystalss werweree analyseanalysedd bbyy powdepowderr X-raX-rayy diffractiondiffraction,, anandd FormatioFormationn conditionsconditions ththee mineraminerall wawass identifieidentifiedd aass natrolitenatrolite.. ThThee developmendevelopmentt ooff natrolitnatrolitee iinn crackcrackss iiss A meameann ooff foufourr microprobmicroprobee analyseanalysess ooff a relaterelatedd ttoo post-obductiopost-obductionn ophioliteophiolite gem-qualitgem-qualityy natrolitnatrolitee frofromm ththee BelBelaa ophiolitophiolitee deformatiodeformationn anandd ttoo hydrothermahydrothermall activitactivityy iiss listelistedd iinn Table 1. I. Data Data were were collected collected withwith alonalongg faultfaultss (Sarwar(Sarwar,, 19921992;; BannerBannertt et ah,aI., aann enlargeenlargedd beabeamm diameterdiameter,, anandd correctedcorrected 1992)1992).. ThesThesee causecausedd deformatiodeformationn andand onlinonlinee foforr HHzO20 absorptionabsorption,, assuminassumingg 2H2200 serpentinizatioserpentinizationn ooff ththee peridotitesperidotites,, anandd peperr formulformulaa unitunit.. ThThee chemicachemicall compositioncomposition fracturingfracturing,, boudinagboudinagee anandd metasomatismmetasomatism iiss closclosee ttoo endmembeendmemberr natrolite.. towardtowardss rodingitrodingitee ooff doleritidoleriticc dykesdykes.. ThThee faultfaultss araree paralleparallell ttoo ththee larglargee Chaman,Chaman, Ornach-Nal, and Ghazaband fault systems GemmologicaGemmologicall characteristiccharacteristicss Ornach-Nal, and Ghazaband fault systems {Figure(Figure 2) 2) which which are are the the result resul tof o fextrusion extrusion of o f ThThee refractivrefractivee indiceindicess foforr ththee BelBelaa materiamateriall ththee AfghanistaAfghanistann continentacontinentall blockblockss duduee ttoo ththee havhavee beebeenn determinedeterminedd oonn a gemmologicagemmologicall HimalayaHimalayann collisiocollisionn (e.g(e.g.. TapponnieTapponnierr et ah,aI., refractometerefractometerr aass a = 1.4801.480,, andand y == 1.485. 1.485 .This This 1981)1981)..

Natrolite fromfrom thethe Bela ophiolite,ophiolite, Pakistan Pakistan HeatingHeating experimentsexperiments byby VanVan ReeuwijkReeuwijk Chan,Chan, T.T.,T.T., andand Chao,Chao, G.Y.,G.Y., 1980.1980. TetranatroliteTetranatrolite fromfrom MontMont (1972)(1972) showedshowed thatthat natrolitenatrolite dehydratesdehydrates andand Saint-Hilaire,Saint-Hilaire, Quebec.Quebec. Can. Mineral.,Mineral, 18,18, 77-8477-84 Chao,Chao, G.Y.,G.Y., 1980.1980. Paranatrolite,Paranatrolite, a newnew zeolitezeolite fromfrom MontMont transforms to metanatrolite at 285°C under transforms to metanatrolite at 285°C under St-Hilaire,St-Hilaire, Quebec.Quebec. Can. Mineral.,Mineral, 18,18, 85-885-8 atmosphericatmospheric pressure.pressure. OnOn thethe otherother hand,hand, Dunn,Dunn, P.J.,P.J., 1976.1976. GemmologicalGemmological notes.notes. /J.. Gemm., 15,15,113-1 113-188 natrolitenatrolite cacann growgrow underunder atmosphericatmospheric Hay,Hay, RL.,R.L., 1966.1966. ZeoliteZeolite weatheringweathering iinn thethe OlduvaiOlduvai Gorge,Gorge, conditionsconditions inin salinesaline lakelake basins.basins. InIn naturalnatural Tanzania.Tanzania. Geol. Soc. Am. Bull,Bull., 74,74, 1281-1281-66 hydrothermalhydrothermal assemblagesassemblages fibrousfibrous zeoliteszeolites Jones,Jones, AG.,A.G., 1960.1960. Reconnaissance geology of part of West Pakistan: a Colombo Plan cooperative project report. generallygenerally occuroccur inin thethe highesthighest temperaturetemperature GovernmentGovernment ofof Canada,Canada, Toronto,Toronto, 550550 zonezone (Alberti(Alberti et al.,ah, 1995).1995). Thus,Thus, comparisoncomparison Judin,Judin, M.I.,M.I., 1963.1963. JadeiteJadeite andand natrolitenatrolite rocksrocks inin ultrabasicsultrabasics withwith similarsimilar occurrencesoccurrences andand thethe presencpresencee ooff fromfrom BorusBonis MountainsMountains (West(West Jajans)Jajans) andand theirtheir genesisgenesis andraditeandradite garnet,garnet, vesuvianitevesuvianite andand xonotlitexonotlite (in(in Russian).Russian). Izv. Acad. Nauk. SSSR Ser. Geol.,Geol, 4,4, 78-9878-98 Klaproth,Klaproth, M.H.,M.H., 1803.1803. Xv.XV. ChemischeChemische UntersuchungUntersuchung desdes suggest that formation of the Bela natrolites suggest that formation of the Bela natrolites Natroliths.Natroliths. Ces.Ges. Naturforsch. Freunde Berlin N. Schr., 4,4, tooktook placplacee atat 150-285°C.150-285°C TheThe proposedproposed low­low- 243-8243-8 temperaturetemperature hydrothermalhydrothermal originorigin ofof thethe KroghKrogh Andersen,Andersen, E.,E., Dano,Dano, M.,M., andand Petersen,Petersen, O.v.,O.V., 1969.1969. natrolitesnatrolites isis alsoalso consistentconsistent withwith a stronglystrongly TheThe mineralogymineralogy ofof Ilimausaq.Ilimausaq. XIII.XIII. A tetragonaltetragonal orderedordered natrolitenatrolite structurestructure (Alberti(Alberti et al.,ah, natrolitenatrolite.. Medd. Gronland, 181,181, 1-191-19 KroghKrogh Andersen,Andersen, E.,E., KroghKrogh AndersenAndersen I.G.,I.G., andand Ploug­Ploug- 1995)1995) whichwhich isis indicatedindicated byby itsits Si/Si/A All ratioratio ooff Sorensen,Sorensen, G.,G., 1990.1990. DisorderDisorder inin natrolites:natrolites: structurestructure ca. 1.5.1.5. determinationsdeterminations ofof threethree disordereddisordered natrolitesnatrolites andand oneone lithium-exchangedlithium-exchanged disordereddisordered natrolite.natrolite. Eur. J. Mineral, 2,2, 799-807799-807 ConclusionConclusion Laurent,Laurent, G.,G., 1941.1941. LuminescencLuminescencee ofof mineralsminerals withwith specialspecial referencereference ttoo quartzquartz andand nephelinenepheline frofromm SwedishSwedish NatroliteNatrolite isis probablprobablyy notnot anan unusualunusual localities.localities. Ceo!.Geol. Forem.Forem. Stockholm, Stockholm, Forh.,Fork., 63,63 ,59-83 59-83 mineralmineral inin PakistanPakistan andand cancan bebe expectedexpected inin Mahmood,Mahmood, K,K., Boudier,Boudier, E,F., Gnos,Gnos, E.,E., Monie,Monie, P.,P., andand 40 39 vugsvugs inin alkalinealkaline lavaslavas oror inin hydrothermalhydrothermal NicolasNicolas,, A,A., 1995.1995. 40 ArAr/ /,9A Arr datindatingg ooff thethe veinsveins associatedassociated withwith alkalinealkaline intrusions,intrusions, asas emplacementemplacement ofof thethe MuslimMuslim BaghBagh ophiolite,ophiolite, Pakistan.Pakistan. wellwell asas inin alkalinealkaline lakelake deposits.deposits. TheThe Tectonophysics, 250,250,169-8 169-811 312 Mazzi,Mazzi, E,R, Larsen,Larsen, A.O.AO.,, Gottardi,Gottardi, G.,G., andand Galli,Galli, E.E.,, 1986.1986. developmentdevelopment ofof largelarge idiomorphiidiomorphicc gem­gem- GonnarditeGonnardite hashas thethe tetrahedraltetrahedral frameworkframework ofof qualityquality crystalscrystals atat thithiss localitylocality isis unusualunusual andand natrolite:natrolite: experimentalexperimental prooprooff withwith a samplesample fromfrom thethe occurrenceoccurrence isis interestinginteresting forfor mineralmineral NorwayNorway.. Neues Jahrb. Mineral. Monatsh.,Monalsh., 1986(5),1986(5), collectors,collectors, bubutt itit isis notnot ofof economiceconomic 219-28219-28 Nawaz, R, 1988. Gonnardites and disordered natrolite­ importance.importance. Nawaz, R., 1988. Gonnardites and disordered natrolite- groupgroup minerals:minerals: theirtheir distinctiondistinction andand relationsrelations withwith mesolite,mesolite, natrolitenatrolite andand thompsonite:thompsonite: Min. Mag., 5252,, 207-19207-19 ReferencesReferences Pauling,Pauling, L.,L., 1930.1930. TheThe structurestructure ofof sodiumsodium andand calciumcalcium Alberti,Alberti, A,A., Cruciani,Cruciani, G.,G., andand Dauru,Dauru, I.,I., 1995.1995. Order-disorderOrder-disorder aluminosilicates.aluminosilicates. Proc. Nat. Acad. Sci., USA, 16,16, 453-9453-9 inin natrolite-groupnatrolite-group minerals.minerals. Eur. J.J. Mineral., Mineral, 7,7,501- 501-88 Poitevin,Poitevin, E.,E., 1938.1938. NatroliteNatrolite fromfrom thethe EasternEastern Townships,Townships, Allemann,Allemann, E,R, 1979.1979. TimeTime ofof emplacementemplacement ofof thethe ZhobZhob Quebec.Quebec. Univ. Toronto Stud. Geol. Ser., 40,40, 63-563-5 ValleyValley ophiolitesophiolites andand BelBelaa ophiolites,ophiolites, BaluchistanBaluchistan Sarwar,Sarwar, G.,G., 1992.1992. TectoniTectonicc settingsetting ofof thethe BelaBela ophiolites,ophiolites, (preliminary(preliminary report).report). In:In: Farah,Farah, A.,A., andand DejongDeJong,, KAK.A. southernsouthern Pakistan.Pakistan. Tectonophysics, 207,207, 359-81359-81 (eds),(eds), Geodynamics of Pakistan. Geol.Geol. Survey,Survey, Pakistan,Pakistan, Tapponnier,Tapponnier, P.,P., Mattauer,Mattauer, M.,M., Proust,Proust, E,F., andand Quetta,Quetta, 215-42215-42 Cassaigneau,Cassaigneau, C,C, 1981.1981. MesozoicMesozoic ophiolites,ophiolites, structuresstructures Anthony,Anthony, J.W.,J.W., Bideaux,Bideaux, RA,R.A., Bladh,Bladh, KW.,K.W., andand Nichols,Nichols, andand large-scalelarge-scale tectonictectonic movementsmovements inin Afghanistan.Afghanistan. M.C,M.C., 1995.1995. Manual of Mineralogy, Vol. II, Silicates and Earth Planet. Sci. Lett.,Lett, 52,52, 355-71355-71 silica. MineralMineral DataData Publishing,Publishing, Tucson,Tucson, 904904 pppp Taylor,Taylor, W.H.,W.H., Meek,Meek, CA,C.A., Jackson,Jackson, W.w.,W.W., 1933.1933. TheThe Artioli,Artioli, G.,G., Smith,Smith, J.v.,J.V., anandd Kvick,Kvick, A.,A., 1984.1984. NeutronNeutron structurestructure ofof fibrousfibrous zeolites.zeolites. Z.Z. Kristallogr. 84,84, 373-9373-988

diffractiondiffraction studystudy ofof natrolite,natrolite, Na2AI2Si30!O"2H20,Na2Al2Si3O10.2H2O, atat VanVan Reeuwijk,Reeuwijk, L.P.,L.P, 1972.1972. High-temperaturHigh-temperaturee phasesphases ooff 2020 K. Acta Cryst., C40, 1658-61658-622 zeoliteszeolites ofof thethe natrolitenatrolite group.group. Am. Mineral,Minera!., 5757,, Bannert,Bannert, D.,D., Cheema,Cheema, A,A., Ahmed,Ahmed, A,A., andand Schaefer,Schaefer, U.,U., 499-510499-510 1992.1992. TheThe structuralstructural developmentdevelopment ofof ththee WesternWestern FoldFold Wight,Wight, W.W.,, 1996.1996. TheThe gemsgems ofof MontMont Saint-Hilaire,Saint-Hilaire, Quebec,Quebec, Belt,Belt, Pakistan.Pakistan. Geolog. Jahrb., Jahrb., B80, B80 ,3-60 3-60 Canada.Canada. /J.. Gemm., 25,25, 24-4424-44

J./. Cemm.,Gemm., 1998,1998,26, 26, 5,5,308-312 308-312 Heat treatment of milky sapphires from the Mogok stone tract, Myanmar

U Hla Kyi1, P. Buchholz2 and D. Wolf2 1. Department of Geology, University of Yangon, Yangon, Myanmar 2. Institut für Mineralogie, TU Bergakademie Freiberg, Brennhausgasse 14, 09596 Freiberg, Germany

ABSTRACT: Heating experiments on Myanmar geuda sapphires indicate that the most beautiful blue stones are obtained by heating to temperatures about 1600°C.

Keywords: geuda, heat treatment, Myanmar, sapphire

here are numerous reports in the (iii) some transparent to semi-translucent literature about heat treatment of waxy whitish or colourless sapphires Tgeuda stones from Sri Lanka with intense silk turned into light to (e.g. Nassau, 1984; Ediriweera and Perera, medium blue, suitable for faceting 313 1989; Hughes, 1990; Hurlbut and Kammerling, (1800°C, 120 minutes) (Themelis, 1992). 1991; Webster, 1994) and they are well known The authors recently had a chance to among gemmologists, but reports of heat examine geuda-like sapphires from the treatment of geuda-like sapphires from the Mogok stone tract and the opportunity to Mogok stone tract, Myanmar, are still scarce. treat some of these stones (Figure 1, A-D). Geuda-like sapphires from the Mogok stone The stones were heated from room tract generally appear milky or contain temperature using a supertherm high- abundant silk, in a range of pale colours temperature furnace model HT 08/17 in an including waxy-white to colourless, yellowish, oxidizing atmosphere and under bluish, etc. (Themelis, 1992). Heat-treatment atmospheric pressure in all experiments. experiments of Upper Myanmar stones Heating started with a rise of 10°C per carried out under reducing atmospheres in the minute up to 1200°C. The temperature was past have shown that held at 1200°C for two hours and then the (i) translucent to opaque white/milky/ furnace was cooled to room temperature bluish sapphires characterized by a dull over a period of eight to ten hours. The blue appearance turned to lighter blue, results were surprising: the milky sapphires opaque or translucent, suitable for turned to transparent or translucent cabochons (1800°C, 60 minutes), colourless stones with the exception of a very (ii) translucent to semi-translucent, white to light blue milky sapphire with zonal pale bluish sapphires characterized by a structure (Figure ID), which turned white. dull appearance turned medium to light Next, the temperature was raised to bright beautiful blue, very transparent, 1300°C, also starting from room temperature suitable for faceting (1750°C, with a rise of 10°C per minute and held for 30 minutes), and two hours, but the results were the same as

© Gemmological Association and Gem Testing Laboratory of Great Britain ISSN: 1355-4565 314 314

Figure 1A-D:1 A-D: Geuda-like, milky sapphires from Figure 2 A-D: Medium blue to beautiful blue the Mogok stone tract before heatheat treatment.treatment. sapphires fromfrom the Mogok stone tract after heat treatment at 1600°C.

J. Gemm., 1998, 26, 5, 313-315313-315 thosthosee obtaineobtainedd atat 1200°C.1200°C RepetitioRepetitionn ofof thethe experimenexperimentt ttoo a temperaturetemperature ofof 1400°C1400°C causedcaused nnoo furthefurtherr dramaticdramatic changechangess inin ththee sapphires.sapphires. AtAt a temperaturetemperature ooff 1500°C,1500°C, thethe heatingheating D perioperiodd wawass muchmuch longerlonger thathann foforr thethe LOWPOT PL o treatmenttreatmentss describeddescribed aboveabove,, anandd thithiss causedcaused thethe coloucolourr ooff somesome milkmilkyy sapphiressapphires ttoo changechange ttoo mediumediumm blueblue.. TheThe light-blulight-bluee milkymilky sapphiresapphire whichwhich hadhad turneturnedd ttoo whitewhite atat 1200°C1200°C alsoalso changechangedd ttoo blubluee atat 1500°C.1500°C. WhenWhen ththee temperaturtemperaturee waswas raiseraisedd toto 1600°C1600°C anandd thethe heatinheatingg perioperiodd furthefurtherr extendedextended,, ththee colourcolour dramaticallydramatically changechangedd frofromm mediummedium blueblue ttoo a beautifubeautifull blueblue asas shownshown inin Figure 2 A-D.A-D. WhenWhen ththee temperaturtemperaturee waswas increasedincreased toto Th 1700°C1700°C anandd ththee perioperiodd ooff heatinheatingg increasedincreased overover thathatt usedused atat 1600°C,1600°C, ththee beautifulbeautiful blueblue sapphiresapphire turneturnedd ttoo mediummedium blueblue.. OnOn ththee basisbasis ooff thesthesee preliminarypreliminary resultsresults oonn a smallsmall samplesample ofof geuda-likegeuda-like sapphiressapphires frofromm MyanmaMyanmarr itit wouldwould seemseem thatthat ththee bestbest resultsresults araree obtainedobtained whewhenn thethe temperaturetemperature rangerange doesdoes notnot exceedexceed 1600°C1600°C iinn anan oxidizingoxidizing atmospheratmospheree (d.(cf. resultsresults obtainedobtained byby ThemelisThemelis,, 1992).1992). FurtheFurtherr experimentaexperimentall detaildetailss areare availableavailable fromfrom ththee seniorsenior author.author. 315315

AcknowledgementsAcknowledgements TheThe authorauthorss woulwouldd likelike toto expressexpress theirtheir sinceresincere thanksthanks ttoo ProfessorProfessor DDrr R.BR.B.. Heimann,Heimann, InstituInstitutt fufurr MineralogieMineralogie,, TVTU BergakademieBergakademie FreibergFreiberg,, GermanyGermany,, foforr allowingallowing themthem toto useuse Diamond grading service ththee superthermsupertherm high-temperaturhigh-temperaturee furnace,furnace, Diamonestablishedd gradin Ing servic1980 e andand MrMrss Hengst,Hengst, forfor patientlpatientlyy operatingoperating thethe established in 1980 furnacefurnace foforr severalseveral weeksweeks.. ThThee provisioprovisionn ofof a each diamond graded by researchresearch grangrantt bbyy DAADDAAD,, GermanyGermany,, isis alsoalso threeEach diamonexperIencedd grade gradersd by gratefullygratefully acknowledged.acknowledged. three experienced graders Report based on the current Report based on the current ReferencesReferences International grading proceduresinternationa for colourl gradin andg clarity Ediriweera,Ediriweera, R.N.,R.N., andand PereraPerera,, S.L,S.L, 1989.1989. HeaHeatt treatmentreatmentt ooff procedures for colour and clarity GeudaGeuda stonesstones - spectralspectral investigation.investigation. /J.. Gemm., 21(7), 21(7) , 403-4403^ Whether buying or seiling, HughesHughes,, R.R,, 1990.1990. Corundum. Butterworth-Heinemann.,Butterworth-Heinemann. , theWhethe londonr buyin DIamondg or selling Report, LondonLondon.. 314314 pppp assuresthe Londo the prestigen Diamon ofd your Repor stonet HurlbuHurlbutt JrJr,, C.S.,C.S., anandd Kammerling,Kammerling, RC.R.C. (eds)(eds),, 19911991.. assures the prestige of your stone Gemology, 2nd 2n dedn. edn John. Joh nWiley Wile y& &Sons, Sons New, New York. York . 336pp336 pp NassauNassau,, K.K.,, 1984.1984. Gemstone enhancement.enhancement. Butterworth­ Butterworth- The Cem ~stfng Laboratory of C~at 8rt n HeinemannHeinemann,, LondoLondonn ThemelisThemelis,, T.T.,, 1992.1992. The heat heat treatment treatment of rubyof ruby and andsapphire. sapphire. TheACTle Gem 27 Testin Grevllleg Laborator stTee Londony of Grea EC1Nt Britai &TNn GemlaGemlabb Inc.Inc.,, Houston.Houston. 236236 pppp TelephoneGAGTL, 27 .Crevill 0171·4()Se Street m1, LondoFax: 0171·8319479n EC1N 8TN WebsterWebster,, R,R., 1994.1994 .Gems, Gems, 5th 5t hedn. edn Butterworth-Heinemann,. Butterworth-Heinemann , Telephone: 0171-405 3351 Fax: 0171-831 9479 Oxford.Oxford. 10261026 pppp

Heat treatmenttreatment of ofmilky milky sapphires sapphires from fromthe Mogok the Mogokstone tract, stone Myanmar tract, Myanmar Laser-induced luminescence of emeralds from different sources

Inessa Moroz1, Gerard Panczer2 and Michael Roth3 1. Institute of Earth Sciences, The Hebrew University of Jerusalem, 91904 Jerusalem, Israel 2. Laboratoire de Physico-Chimie des Materiaux Luminescents, Universite Claude Bernard - Lyon 1, 69622 Villeurbanne Cedex, France 3. School of Applied Science, The Hebrew University of Jerusalem, 91904 Jerusalem, Israel

ABSTRACT: Preliminary spectroscopic analysis in the red range of the spectrum between 674 and 679 nm using the new laser-induced (time- resolved) photoluminescence (LPL) technique, has been carried out on six natural emeralds from Afghanistan, Brazil, Colombia, Nigeria, Russia and Zambia, and one hydrothermally grown synthetic emerald. Emeralds from different sources have distinctive luminescent spectra and the usefulness of the results is evaluated. Although the luminescence spectra of emeralds from Afghanistan, Russia and Zambia are similar to that of the synthetic emerald, they show an additional 'bulge' towards the longer wavelength. The artificial emerald displays 316 about three times greater intensity of luminescence than that shown by the natural emeralds.

Keywords: emerald, laser, photoluminescence, spectrum

Introduction Schwarz, 1991; Moroz, 1996). They are located in regions where acidic magmas have A selection of emeralds from six gem- penetrated country rocks in the vicinity of mining regions in Afghanistan (Panjshir), basic and ultrabasic rocks, and formed Brazil (Carnaiba), Colombia (Muzo), phlogopite-bearing bodies of rock related to Nigeria (Jos), Russia (Malishevo), and distinctive greisens which contain actinolite Zambia (Kitwe), and one synthetic or tremolite and variable quantities of talc, hydrothermally grown emerald were chlorite, quartz, albite, chromite, ilmenite, chemically analysed with the electron magnetite, apatite, tourmaline, fluorite and microprobe (Moroz and Eliezri, 1998). The so on (Moroz, 1978; 1996). Some of these emeralds are chemically not homogeneous minerals were identified as inclusions in our for the most part and display colour zoning samples of emeralds from these deposits that correlates directly with variations in (Moroz, 1997). In contrast to the emeralds chromium content. Emerald occurrences in from the 'schist-type' deposits, which have Afghanistan, Brazil, Russia and Zambia relatively high magnesium and sodium belong to 'schist-type' deposits (Beus and contents, the Colombian and Nigerian Mineev, 1974; Kiyevlenko et al, 1974; emeralds are low in magnesium and sodium. Moroz, 1978; Sliwa and Nguluwe, 1984; This suggests that the rocks in the vicinity

© Gemmological Association and Gem Testing Laboratory of Great Britain ISSN: 1355-4565 ApparatuApparatuss ThTIlee principl principlee characteristic characteristicss o fof th thee lumi lumi­ ­ intensifieintensifiedd CCCCDD camercameraa anandd aann opticaopticall nescencnescencee equipmen equipmentt ar aree a sas follow followss (Figure (Figur e1): 1) : microscopemicroscope. Thi. TIUss detector detector,, triggere triggeredd b byy th thee PulsePulsedd U INV radiatio radiationn (33 (3377 nm nm)) fro fromm a a laserlaser,, provide providess quic quickk time-resolve time-resolvedd spectrspectraa nitrogenitrogenn laselaserr bea beamm ofof 2 020 jxse ~secc pulspulsee acquisitioacquisitionn a tat a ananometr nanometree scal scalee a ass wel welll a ass duratiodurationn focuse focusedd o non th thee tes testt specime specimenn i sis selectivselectivee separatioseparationn ooff overlappinoverlappingg useusedd t oto excit excitee photoluminescence photoluminescence. . ThThee emissioemissionn spectrspectraa frofromm 202000 n nmm uupp toto emitteemittedd ligh lightt is isdirecte directedd fro fromm th thee specime specimenn 909000 nm nm. A. Ann optica opticall spectra spectrall analyser analyser,, base basedd toto th thee inle inlett sli slitt o fof th thee monochromator monochromator. Th. Thee oonn th thee detecto detectorr connecte connectedd wit withh a a P PCC witwithh luminescencluminescencee spectrspectraa ofof ththee emeralemeraldd INSTASPETNSTASPECC softwaresoftware,, wawass useusedd toto samples were recorded in the Laboratoire produce the luminescence spectra. The samples were recorded in the Laboratoire produce the luminescence spectra. The de Physico-Chimie des Materiaux method is non-destructive. All de Physico-Chimie des Materiaux method is non-destructive. All Luminescents, Lyon Universite Claude investigations were performed at room Luminescents, Lyon Universite Claude investigations were performed at room Bernard, using an Instaspec V detector temperature in the air. The general data Bernard, using an Instaspec V detector temperature in the air. The general data which combines the advantages of a new collection time is less than 20 ~sec . which combines the advantages of a new collection time is less than 20 jxsec.

Figure 1: Schematic presentation of the time-resolved photoluminescence equipment. Figure 1: Schematic presentation of the time-resolved photoluminescence equipment. Spectrophotometer Spectrophotometer(entrance (entranceslit 100 !Am ) grating slit 100 \xm) gratin400 tlgmm sample 40120 0t/m0 t/mmm samplundeer 1----+---"+) 120 16000 t/mt/ mmm undemicror scope L1600 t/mm microscope 317317

intensified CCD Dye eT] intensified CCD + Laser UV pulses generator Laser pulse(>s orgenerato =4 n )r 337 nm (> or = 4 ns) 337 nm

HHH • D D IrS ®\ ODD [B| B B B P IX H H a o o o o o o o PC 200 MHz Interface

pulses ••••h> • • • •r have low magnesium contents. Neither model for the occurrence of Nigerian ultramafic nor mafic rocks have been found gemstones in greisen associations of in the vicinity of Colombian emerald Mesozoic alkali granite ring complexes with deposits and some authors proposed an albitization processes has been established epigenetic hydrothermal-sedimentary model (Schwarz et al., 1996). Chromium in general, for them (Giuliani et al., 1995); a genetic is held responsible for the green colour of

Laser-induced luminescence of emeralds from different sourcessources TablTablee II.. Ranges Ranges ofof composition composition ofof emeralds emeralds fromfrom differentdifferent sourcessources

CountryCOllntry Afghanistan RllssiaRussia Zambia BrazilBrazil ColombiaColombia NigeriaNigeria SynthSyntheticetic Deposit PanjshirPanjs/lir MalishMalishevoevo KitwKitwee CarnaibaCarnaiba MuMuzozo JosJos HydrothHydrothermalermal

No. of samples 3 2 33 22 22 33 33

No. of analyses 25 16 1515 1155 1414 1717 88

WtWt%%

SiGSi022 62.09-66.662.09-66.600 61.51-64.461.51-64.400 58.92-65.7258.92-65.72 62.21~3.0462.21-63.04 62.02-66.5062.02-66.50 6363.40-67.1. ~7.155 6262.93-65.3. 9~5.300 ! AIPAIA3 14.45-17.014.45-17.099 16.89-17.516.89-17.599 13.63-15.2613.63-1526 15.01-16.0315.01-16.03 1616.79-18.0.79-18.022 17.84-19.1517.84-19.15 17.23-18.1017.23-18.10 FeFeOO 0.21-1.10.21-1.166 b.d.-0.5b.d.-O.522 0.47--{).970.47-0.97 0.52-0.850.52-0.85 b.db.d.-0.2.--{).255 00.09-0.7.09-0.733 b.d.-O.30b.d.-0.30

MgMgOO 0.95-1.80.95-1.899 0.60-1.20.60-1.299 1.84-2.341.84-2.34 1.51-2.261.51-2.26 0.7-0.760.7-0.76 b.d.--{).08b.d.-0.08 0.19-0.460.19-0.46

0.01-1.6] b.d.-O.65 0.10-0.67 0.0]-0.58 Naap20 0.01-1.61 0.62-1.10.62-1.166 00.96-1.6.96-1.655 0.68-1.380.68-1.38 b.d.-0.65 0.10-0.67 0.01-0.58

Cr 0 b.d.-O.16 b.d.-O.30 0.23-0.53 0.02-0.09 b.d.--{).29 b.d.-O.19 0.20-0.88 Cr22033 b.d.-0.16 b.d.-0.30 0.23-0.53 0.02-0.09 b.d.-0.29 b.d.-0.19 0.20-0.88

NoteNote.. Composition Compositionss wer weree determine determinedd b byy electro electronn prob probee microanalysis microanalysis.. Be BeOO anandd HH220 werweree nonott measured measured.. ContentContentss ooff Ca Ca,, KK,, TiTi,, MnMn,, VV,, CuCu,, NiNi,, CoCo,, ZnZn,, CCss anandd SS rangrangee frofromm belobeloww detectiodetectionn toto minominorr amountamountss leslesss thathann 0.50.5%% ooff oxideoxide., b.db.d.. == belobeloww detectiodetectionn levellevel..

emeraldemerald,, bubutt vanadiuvanadiumm alsalsoo mamayy contributecontribute.. ResultResultss 318 SomSomee samplesampless frofromm ColombiaColombia,, NigeriNigeriaa anandd 318 The spectral range 675-679 nm is the BraziBrazill (Carnaiba(Camaiba)) havhavee loloww chromiuchromiumm valuesvalues,, The spectral range 675-679 nm is the mosmostt informativinformativee foforr analysinanalysingg anandd som somee ma mayy contai containn u upp t too 0.30.3%% VV203 (Table(Table I).I). 2 3 luminescencluminescencee ooff ththee emeraldsemeralds.. ThThee commocommonn The seven samples were studied by The seven samples were studied by spectruspectrumm o off emeraldemeraldss i iss aa broabroadd ban bandd i inn ththee luminescence spectroscopy using a laser­ luminescence spectroscopy using a laser- 'red'red'' parpartt aatt 676755 ttoo 676777 nnmm duduee ttoo CrCr3+3+.. induceinducedd (time-resolved(time-resolved)) photoluminescencphotoluminescencee The emerald spectra (Figure 2) of the six (LPL(LPL)) techniquetechnique.. ConventionaConventionall techniquetechniquess The emerald spectra (Figure 2) of the six samples of natural emerald and one currentlcurrentlyy useusedd ttoo obtaiobtainn luminescencluminescencee samples of natural emerald and one synthetic hydrothermal emerald are spectrspectraa ooff mineralmineralss araree fafarr frofromm beinbeingg perfecperfectt synthetic hydrothermal emerald are characterized by the dominant role of Cr anandd araree applicablapplicablee onlonlyy ttoo aa limitelimitedd numbenumberr characterized by the dominant role of Cr appearing at room temperature as a broad ooff luminescent'luminescent'' gemsgems.. EmeralEmeraldd iiss usuallusuallyy appearing at room temperature as a broad red band. The emeralds from Afghanistan, considereconsideredd aa 'non-luminescent'non-luminescent'' gegemm (Smith(Smith,, red band. The emeralds from Afghanistan, Russia and Zambia, which belong to 19721972;; SamsonoSamsonovv anandd TuringueTuringue,, 1984)1984),, bubutt ththee Russia and Zambia, which belong to 'schist-type' deposits, show an additional luminescencluminescencee intensitintensityy generategeneratedd bbyy ththee 'schist-type' deposits, show an additional 'bulge' structure in the curves (Figure 2, laselaserr iiss significantlsignificantlyy largelargerr thathann ththee 'bulge' structure in the curves (Figure 2, curves 1-3). Apart from the broad red band luminescencluminescencee exciteexcitedd bbyy conventionaconventionall lighlightt curves 1-3). Apart from the broad red band A 678 sourcesourcess anandd ththee LPLPLL techniqutechniquee cacann bbee thertheree iiss aa banbandd aatt X mamax""x « 678 nnmm iinn thesthesee applieappliedd effectiveleffectivelyy iinn mosmostt mineralsminerals,, samplessamples.. especiallespeciallyy thos thosee containincontainingg dopandopantt ions ions.. ThiThiss ThThee artificiaartificiall emeralemeraldd displaydisplayss abouaboutt techniqutechniquee iiss alsalsoo attractivattractivee aass iitt iiss nonnon­­ threthreee timetimess greategreaterr intensitintensityy ooff destructivedestructive.. IInn thithiss contributiocontributionn ththee luminescencluminescencee thathann thathatt showshownn bbyy eaceachh ooff preliminarpreliminaryy resultresultss ooff ththee LPLPLL techniqutechniquee ththee naturanaturall emeraldemeraldss (Figure(Figure 22,, curvcurvee 7)7).. ThThee carriecarriedd ououtt oonn aa selecteselectedd numbenumberr ooff ththee luminescenluminescentt spectrspectraa ooff ththee naturanaturall emeralemeraldd chemicallchemicallyy analyseanalysedd emeraldemeraldss araree discussediscussedd specimenspecimenss frofromm AfghanistanAfghanistan,, RussiRussiaa anandd anandd a a possiblpossiblee applicatio applicationn o off th thee techniqutechniquee ttoo ZambiZambiaa araree similasimilarr iinn forformm ifif nonott intensitintensityy characterizcharacterizee thesthesee gemgemstoness tones iiss evaluatedevaluated.. ttoo ththee spectruspectrumm ooff ththee synthetisyntheticc emeraldemerald..

/J.. Gemm.,Gemm., 1998,1998,26,5,316-320 26, 5, 316-320 xlOxlO4' .------,---,------, 5V ) ^7~ ~ //yV \ "~8 i \- a! 7 /// ~ .l!l %v \ §§ 0.0.55 u I (3o V\ U

6 ^^ now pm 1 1 ~T 676755 680680 WavelengtWavelengthh nmnm

Figure 2: LPL spectra of seven emeralds (the crystallographic c-axis is oriented parallel to the laserlaser beam) fromfrom thethe followingfollowing sources:sources: 1 1 Afghanistan; Afghanistan; 22 Russia; Russia; 3 3 Zambia; Zambia; 4 4 Brazil Brazil;; 5 5 Colombia; Colombia; 6 6Nigeria; Nigeria; 7 syntheticsynthetic hydrothermalhydrothermal emerald.emerald.

DiscussionDiscussion throughthrough otheotherr luminescenceluminescence bandbandss thatthat mamayy bbee typicatypicall foforr certaicertainn occurrencesoccurrences ThThee crystacrystall structurestructuress ooff mosmostt mineralsminerals (Mesyat(Mesyatss et ah,al. , 1992).1992). TheThe stonestoness fromfrom 319 havhavee defectdefectss whicwhichh araree usuallusuallyy presenpresentt asas AfghanistaAfghanistann anandd ZambiZambiaa contaicontainn appreciableappreciable 319 dislocationdislocationss oorr aass 'dopan'dopantt ionsions'' anandd areare,, inin iroironn concentrationconcentrationss (Table I). AccordinAccordingg toto essenceessence,, ththee luminescencluminescencee centrecentress (LO(LC) iinn thethe PlatonoPlatonovv et ahal. (1984(1984,, p.. 60)60),, ththee colourincolouringg ooff visiblvisiblee spectraspectrall rangerange.. EverEveryy centrcentree hahass itsits emeraldemeraldss mamayy bbee influenceinfluencedd nonott onlonlyy bbyy iron,iron, characteristicharacteristicc luminescencluminescencee bandbandss anandd lineslines bubutt alsalsoo bbyy otheotherr dopandopantt ionsions,, indudingincluding (Ginzburg(Ginzburg,, 1985).1985). ThThee intensitintensityy ooff a specificspecific 'non-chromophores'non-chromophores'' - foforr instancinstancee magnesiummagnesium spectraspectrall banbandd oorr linlinee iiss determinedeterminedd botbothh byby becausbecausee thetheyy mamayy changchangee ththee proportionproportionss ooff ththee numbenumberr ooff centrecentress containecontainedd iinn thethe ththee chromiachromiann polyhedronpolyhedronss iinn ththee berylberyl mineraminerall anandd bbyy ththee concentratioconcentrationn ooff structurstructuree anandd shiftshift ththee chromiuchromiumm bandsbands luminescencluminescencee absorptioabsorptionn centrecentress (LCA).(LCA). towardtowardss longelongerr wavelengthswavelengths.. WWee reportreport 2+ 22+ SomSomee dopandopantt ionionss sucsuchh aass FeFe2+ anandd Cu + maymay elsewherelsewheree (Moro(Morozz anandd EliezriEliezri,, 19981998)) onon completelcompletelyy absorabsorbb oorr quencquenchh luminescence.. heighteneheightenedd concentrationconcentrationss ooff magnesiumagnesiumm inin ThThee mosmostt importanimportantt dopandopantt ioionn inin emeralemeraldd samplesampless frofromm ZambiZambiaa (t(too 2.32.344 wt%)wt%),, 3+ 3+ emeralemeraldd iiss Cr 3+ iinn octahedraoctahedrall AlAP+ sitessites AfghanistaAfghanistann (u(upp ttoo 1.71.733 wt%wt%)) anandd RussiRussiaa (up(up (Woo(Woodd anandd NassauNassau,, 19681968;; TaraschanTaraschan,, 19781978;; ttoo 1.1.33 wt%)wt%);; whicwhichh givgivee risrisee ttoo 're'redd shiftsshifts'' ooff MoroMorozz et ah,al., iinn press)press).. IItt iiss importanimportantt thathatt thethe ththee Cr33+ absorptioabsorptionn banbandd iinn thesthesee samplessamples wavelengtwavelengthh ooff ththee majomajorr Cr-linCr-linee iinn ththee redred (Moro(Morozz et ah,al., iinn press).. CorrespondinglyCorrespondingly,, anan parpartt ooff ththee spectruspectrumm iiss calibratecalibratedd precisely.precisely. additionaadditionall l^ulge'bulge'' structurstructuree appearappearss aass a longlong 3+ AlonAlongg witwithh ththee CrCr3+ ionionss iinn naturanaturall emeralds,emeralds, wavelengtwavelengthh shouldeshoulderr aatt Xmax«678nJ... max", 678 nmm iinn ththee presencpresencee ooff otheotherr dopantdopantss dependdependss onon ththee luminescencluminescencee spectrspectraa ooff ththee samesame theitheirr chemicachemicall naturnaturee anandd oonn theitheirr concentra­concentra­ samplesampless reportereportedd herheree (Figure 2,, curvecurvess 1-3).1-3). tiotionn iinn ththee geologicageologicall anandd geochemicageochemicall condicondi­­ SucSuchh aann influencinfluencee oonn CrCr3+3+ spectraspectrall bandsbands tiontionss ooff mineraminerall formationformation.. DifferenceDifferencess iinn ththee positiopositionn iinn emeraldemeraldss mamayy alsalsoo bbee exerteexertedd bbyy chemicachemicall compositiocompositionn ooff emeralemeraldd wilwilll showshow otheotherr impuritieimpuritiess sucsuchh aass manganesemanganese,, zinzincc themselvethemselvess eitheeitherr througthroughh ththee distinctivenessdistinctiveness anandd titaniutitaniumm whewhenn thetheyy enteenterr octahedraloctahedral ooff ththee reredd banbandd structurstructuree (Figure 2) oorr positionpositionss iinn ththee emeralemeraldd structurestructure..

Laser-inducedLaser-induced luminescenceluminescence of emeraldsemeralds from different sources ConclusionConclusion Giuliani,Giuliani, O.0.,, CheilletzCheilletz,, A,A., Arboleda,Arboleda, c.,C, Carillo,Carillo, V.v.,, Rueda,Rueda, E,E, anandd BakerBaker,, H.H.,, 1995.1995. AAnn evaporiticevaporitic origioriginn ofof thethe TheThe luminescentluminescent spectraspectra ooff emeraldemeraldss fromfrom parenparentt brinebriness ooff ColombianColombian emeralds:emeralds: fluifluidd inclusioninclusion differentdifferent sourcessources areare presented.presented. ThThee spectraspectra anandd sulphursulphur isotopisotopee evidenceevidence.. European Journal ofof ooff emeraldsemeralds fromfrom Afghanistan,Afghanistan, RussiRussiaa andand Mineralogy, 7(1)7(1),, 151--{;5151-65 Kiyevlenko,Kiyevlenko, Ye.Ya.,Ye.Ya., SenkevichSenkevich,, N.N.N.N.,, anandd GavrilovGavrilov,, A.P.AP.,, Zambia,Zambia, whicwhichh belonbelongg toto 'schist-type''schist-type' 1974.1974. Geology of gemstone deposits: Nedra, MoscowMoscow depositsdeposits,, areare lessless intenseintense thanthan thethe spectrumspectrum MesyatsMesyats,, G.A,G.A., Mikhailov,Mikhailov, S.G.,S.G., Osipov,Osipov, V.V.V.V.,, andand ofof ththee syntheticsynthetic hydrothermallyhydrothermally growngrown Solomonov,Solomonov, V.I.V1.,, 1992.1992. PulsePulsedd cathodoluminescencecathodoluminescence ooff emeraldemerald andand showshow anan additionaladditional 'bulge''bulge' mineralsminerals.. Pisma v Journal Technitcheskoi Fisiki,Fisiki, 18,18,87-9 87-900 Moroz,Moroz, 1.1.,I.I., 1978.1978. PrincipaPrincipall featurefeaturess ofof geochemistrgeochemistryy ooff structure in the luminescence curves. structure in the luminescence curves. emerald-bearingemerald-bearing micaceoumicaceouss metasomatitemetasomatitess fromfrom thethe ThThee investigatioinvestigationn ofof luminescenceluminescence spectraspectra Urals.Urals. Bull. High Education Institutions, Geology and ooff emeraldsemeralds througthroughh thethe laser-inducedlaser-induced Prospecting, 1151:1151:1-2 1-288 Moroz, 1.1., 1996. Geochemistry of the emerald-bearing luminescence (LPL) technique opens up Moroz, I.I., 1996. Geochemistry of the emerald-bearing luminescence (LPL) technique opens up micaceoumicaceouss rockrockss frofromm thethe Urals.Urals. Abstracts of the IsraelIsrael possibilitiepossibilitiess forfor obtaininobtainingg fasfastt andand reliablereliable Geological SocietySociety AnnualAnnual Meeting.Meeting. Eilat,Eilat , MarchMarch 18--21,18-21 , solutionssolutions ttoo a rangerange ofof gemmologicalgemmological 7171 problemsproblems includinincludingg gegemm identification,identification, MorozMoroz,, I.1.,, 1997.1997. MineralMineral inclusioninclusionss iinn emeraldemeraldss fromfrom indicationindication ooff ththee sourcesource ooff a gem,gem, andand differendifferentt depositsdeposits.. Abstracts of the Israel GeologicalGeological Society Annual Meeting. KefaKefarr Gilady,Gilady, Galilee,Galilee, characterizationcharacterization ofof synthetisyntheticc gemstones.gemstones. ApriAprill 15--17,15-17, 7979 Moroz,Moroz, LL,I.I., anandd EliezriEliezri,, LZ.,I.Z., 1998.1998. EmeralEmeraldd chemistrchemistryy fromfrom differendifferentt depositsdeposits:: aann electronelectron microprobmicroprobee study.study. The AcknowledgementAcknowledgementss Australian Gemmologist, 20(2),20(2), 64-964-9 ThiThiss worworkk waswas supportedsupported bbyy ththee WolfsonWolfson Moroz,Moroz, 1.,I., RothRoth,, M.,M., anandd DeichDeich,, V. (in(in press)press).. ThThee visiblevisible absorptioabsorptionn spectroscopspectroscopyy ooff emeraldsemeralds fromfrom differentdifferent FoundationFoundation foforr ScientificScientific ResearcResearchh anandd bbyy thethe depositdepositss LaboratoireLaboratoire dede Physico-ChimiePhysico-Chimie desdes Platonov,Platonov, A.N.AN.,, TaranTaran,, M.N.M.N.,, anandd BalitskyBalitsky,, V.5.V5.,, 1984.1984. MateriauMateriauxx LuminescentsLuminescents,, LyonLyon UniversiteUniversite Nature of gems coloring. NedraNedra,, Moscow.Moscow. 196196 ClaudClaudee Bernard.Bernard. 1.Z.I.Z. EliezrEliezrii (the(the IsraelIsrael Samsonov,Samsonov, J.P.J.P.,, andand TuringueTuringue,, AP.,A.P., 1984.1984. Gems of the USSR.USSR. 320 Ed. V.1. Smimov, Nedra, Moscow. 335 Emerald Cutters Association) provided Ed. V.l. Smimov, Nedra, Moscow. 335 Emerald Cutters Association) provided Schwarz,Schwarz, D.D.,, 1991.1991. AustraliaAustraliann emeraldsemeralds.. The AustralianAustralian representativrepresentativee samples.samples. WWee alsalsoo wishwish toto Gemmologist, 488--97488-97 extenextendd ourour thanksthanks ttoo ProfessoProfessorr E.E. SassSass ofof thethe Schwarz,Schwarz, D.,D., KanisKanis,, LJ., andand KinnairdKinnaird,, J.,J., 1996.1996. EmeraldEmerald andand HebrewHebrew UniversityUniversity ofof Jerusalem,Jerusalem, anandd ttoo thethe greengreen beryberyll fromfrom CentralCentral NigeriaNigeria.. Journal ofof anonymousanonymous refererefereee foforr valuablevaluable suggestions.suggestions. Gemmology, 25(2)25(2),, 117-41117-41 Sliwa,Sliwa, AS.,A.S., andand NguluweNguluwe,, C.A.C.A,, 1984.1984. GeologicaGeologicall settingsetting ofof ZambiaZambiann emeralemeraldd deposits.deposits. Precambrian Research, References 2525,213-28, 213-28 References Smith,Smith, G.F.H.G.EH.,, 1972.1972. Gemstones. ReviseRevisedd ECEC.. Phillips.Phillips. BeusBeus,, AA,A.A., anandd Mineev,Mineev, D.A.D.A,, 1974.1974. ContributioContributionn toto ChapmanChapman andand HallHall,, LondonLondon geologygeology andand geochemistrgeochemistryy ooff thethe emerald-bearingemerald-bearing Taraschan,Taraschan, A.M.AM.,, 1978.1978. Luminescence of minerals. NaukovaNaukova zonzonee Muzo-Coscuez,Muzo-Coscuez, CordilleraCordillera Oriental,Oriental, Colombia.Colombia. durnka,dumka, KievKiev.. 296296 Geol.Ceol. Rudn. Mestorozhd., 16(4),16(4), 18-3018-30 Wood,Wood, D.L.D.L.,, anandd NassauNassau,, K.K.,, 1968.1968. ThThee characterizationcharacterization ooff Ginzburg,Ginzburg, N.LN.L,, 1985.1985. Methods of mineralogical investigations.investigations. beryberyll andand emeralemeraldd byby visiblevisible andand infrareinfraredd absorptionabsorption NedraNedra,, MoscowMoscow.. 263--77263-77 spectroscopy.spectroscopy. American Mineralogist, 5353,, 777--800777-800

J./. Gemm., 1998,1998,26, 26, 5, 289-352289-352 Obsidian from Chile with unusual inclusions

Dr Jaroslav Hyrsl1 and Dr Vladimir Zäcek2 1. Kolin, Czech Republic 2. Czech Geological Survey, Prague, Czech Republic

ABSTRACT: A new type of transparent slightly yellowish obsidian from northern Chile is described and its chemical composition is given. The obsidian has a refractive index of 1.540 and a specific gravity of 2.36; it contains three types of distinct well-crystallized inclusions - hexagonal very strongly pleochroic columnar crystals thought to be indialite (high-temperature polymorph of cordierite), elongated striated rods of sillimanite and tiny parallelepipeds of probable feldspar.

Keywords: Chile, inclusions, indialite, obsidian, sillimanite

Introduction owner. One faceted obsidian is completely transparent and two are slightly milky, their ransparent natural glasses, with the colour being slightly yellowish. The 321 composition of obsidian, are known refractive index of 1.540 is at the higher limit Tfrom many places throughout the for natural obsidians, and the specific gravity world but, unless they are of attractive is 2.36. All three pieces of rough show fine colour and appearance, are not very dark layers, rarely curved, indicating fluidal interesting for the gemmologist or for the structure. Their surfaces are dull, probably as trade. The new material from northern Chile a result of wind erosion. All stones stay is a nice exception especially due to its bright during rotation in the polariscope due wonderful interior with a variety of to the abundant anisotropic inclusions; inclusions. obsidian itself is isotropic. The chemical

Description Figure 1: Faceted obsidians, 17 mm and 14 mm long. Photograph by J. Hyrsl Three cut stones between 7.13 and 12.90 ct and three rough pieces between 5 and 8 g were bought in Brazil in 1997 and 1998 respectively by the first author and they reputedly came from the Atacama desert in northern Chile (see Figure 1). The locality is probably correct, because similar obsidian comes from a nearby region in Peru and has been called 'macusanite' after the regional name (see later). Very little obsidian was found and only a few pieces were transparent enough to be cut according to the

© Gemmological Association and Gem Testing Laboratory of Great Britain ISSN: 1355-4565 Table I.I. ChemicalChemical co compositionmposition of oofbs obsidianidia n from from Chil eChile compa comparedred with mac withusa macusanitenite from Per fromu, ma Peru,rekani marekanitete from from ArizonaArizona andand an an ind indialiteialite inclu inclusionsion from from Chil eChile..

m.%Wt.% 1.1- 2.2. 3. 4.4. Obsidian,Obsidiall, ChileChile Macllsallite,Macusanite, Peru Peru Mnreknllite,Marekanite, USA USA II/din/iteIndialite inclusiol/ inclusion

Si0SiO2z 74.274.200 77.977.988 74.674.644 47.8747.87

Ti0TiO2z 0.00.099 - 0.10.122

A1A12P03J 14.214.266 13.113.166 12.4812.48 3232.3.399 CaCaOO 0.30.333 0.50.544 2.22.255 0.050.05 FeFeOO 0.40.466 1.31.344 0.80.822 7.837.83 MgMgOO 0.00.088 - 0.40.444 7.517.51 MnMnOO 0.20.277 - 0.00.066 1.531.53 3.82 2.46 NaazO20 3.82 - 2.46 0.360.36 K~Op 4.44.488 6.96.988 5.65.666 0.24 Prp205s - - 0.24 SOJ- 0.58 S03" - - 0.58 Cl- CI" - - 0.20.255 TotaTotall 97.997.999 100.0100.000 100.0100.000 9797.5.544

RRII 1.541.5400 1.481.4899 1.4801.480 SG 2.36 2.36 322 SG 2.36 2.36 2.32.333

NB: TotaTotall iroironn isis givegivenn asas FFeOeO; - mean means belobeloww detection;detection; macusanitmacusanite aanalysinalysis frofromm Henn,Henn, 1995;1995; mmarekanitarekanite analysianalysiss frofrom HolzheyHolzhey,, 1996;1996; obsidiaobsidian anand indialitindialite compositioncompositionss fromfrom microprobmicroprobe analyseanalyses bbyy 1.I. Vavrin.Vavrin.

compositioncomposition ooff ththee ChileanChilean obsidianobsidian waswas longeslongestt crystalcrystalss reachreach 1 mm.. TheTheyy sshohow hihiggh studiedstudied usingusing aann EDXEDX micrmicroproboprobee fittedfitted withwith relierelieff witwithh pale interferencinterferencee colourscolours eveveenn inin a LINK-eXLLINK-eXL ssystemystem.. TheThe reresultsultss areare givengiven inin planplanee ppolariseolarisedd light.light. TablTablee I togethetogetherr withwith thethe chemicalchemical TheThe sseconecondd typtypee ofof inclusiinclusioon consistconsists ooff compositionscompositions ofof ttwwo recentlrecentlyy describeddescribed colourlcolourlesesss long rodsrods striatedstriated paralleparallell toto the obsidians,obsidians, marekanmarekanitite frofromm ArizonaArizona cc-axes-axes.. TheThe rarestrarest inclusions aarree tintiny (Holzhey, 1996)1996) andand ''macusanitemacusanite'' fromfrom PeruPeru colourless parallelepipedsparallelepipeds withwith mmonoclinionoclinicc (Henn,(Henn, 1995).1995). TheThe analanalysiysis showsshows highhigh silicasilica oror triclinitriclinicc symmetry.symmetry. AllAll three ttypeypes ooff andand alkalialkali contents andand confirmsconfirms anan originorigin inclusions areare anisotropic,anisotropic, havehave a highhigheer connectedconnected withwith rhyoliticrhyolitic volcanism.volcanism. refractirefractivvee indexindex thanthan obsidianobsidian (measur(measureed byby a BBeckeckee line)line) andand showshow a straightstraight exextinctiotinctionn InclusionsInclusions inin crocrossss polars.polars. AllAll threethree cutcut stonesstones containcontain easilyeasily visiblevisible TheThe blue columnarcolumnar inclusionsinclusions werewere inclusionsinclusions whiwhicch diminishdiminish theirtheir initially interpretedinterpreted asas cordierite fromfrom theirtheir trantransparencsparencyy (see(see FiFiguregure 2). The mostmost strikingstriking sshaphape andand pleochroism,pleochroism, andand thisthis waswas inclusions areare blue columnarcolumnar hexagonalhexagonal cconfirmeonfirmedd by a microprobemicroprobe ananalysialysis wwhichichh crystalscrystals withwith veryvery sstrontrongg pleochroipleochroismsm,, deepdeep indindicateicated a compositionalcompositional formula ofof (M(Mgg1.1117 bluish-violet along c-axes and colourless Feo.68 Mno.i4 Nao.o7 Ca ) (Al Si )O . bluish-violet along c-axes and colourless FeO.68 MnO.14 Nao.07 Cao001.OJ ) 2.07207 (AI3398.98 Sis500.oo ) 0 18 . perpendicularperpendicular toto thethe eelongationlongation.. TheyThey showshow CordieriteCordierite isis veryvery rarerare asas anan incluinclusionsion, hhavinavingg onlyonly twotwo crystallocrystallographigraphicc forms,forms, thethe beenbeen reportedreported byby GiibelinGubelin andand KKoivuloivula (19(199292)) hexagonalhexagonal prismprism andand basalbasal pinacoid,pinacoid, andand thethe onlyonly asas anan inclusioninclusion inin beryLberyl. InIn this ChilChileaeann

J./. GemGemm.,m., 1998,1998, 2626,, 55,, 3321-32321- 323 Figure 2:2: InclusionsInclusions in in the the faceted faceted obsidians obsidians (in crossed (in crossed polarized polarized light). Photographs light). Photographs by J. Hyrsl. by J. Hyrsl.

obsidiaobsidiann ththee inclusioninclusionss araree probablprobablyy notnot (Bousk(Bouskaa et al.,al, 1994).1994). DuDuee ttoo ititss RRII ooff moremore 323323 orthorhombiorthorhombicc cordieritecordierite,, bubutt ititss high­high- thanthan 1.54,1.54, sanidinesanidine andand albitealbite cancan bebe temperaturtemperaturee hexagonalhexagonal polymorphpolymorph,, indialite.indialite. excludeexcludedd aass possibilitiespossibilities,, bubutt itit couldcould bbee a DistinctioDistinctionn betweebetweenn thesthesee polymorphspolymorphs basibasicc plagioclaseplagioclase.. wouldwould onlonlyy bbee possiblpossiblee bbyy X-rayX-ray methods.methods. AlthoughAlthough ththee lonlongg rod-likerod-like inclusioninclusionss areare AcknowledgementsAcknowledgements ververyy similarsimilar ttoo andalusitandalusitee inclusioninclusionss inin PeruvianPeruvian obsidiaobsidiann (macusanite(macusanite)) describedescribedd byby WeWe wouldwould likelike toto thanthankk DrDr 1.I. VavriVavrinn atat thethe GiibelinGubelin anandd KoivulaKoivula (1992)(1992) andand HennHenn (1995)(1995),, CzecCzechh GeologicaGeologicall Survey,Survey, Prague,Prague, foforr micromicro­- whwhoo analyseanalysedd thethemm chemicallychemically,, thetheyy havehave probprobee analysisanalysis,, anandd J.IJ.1.. KoivulaKoivula aatt thethe GIAGIA,, beebeenn identifiedidentified asas sillimanitesillimanite bbyy laserlaser RamanRaman Carlsbad,Carlsbad, U.S.A.,U.S.A., foforr identificationidentification ofof inclu­inclu­ methodmethodss (Koivula,(Koivula, pers.comm.)pers.comm.).. SomeSome rodsrods sionssions inin thethe obsidian.obsidian. werweree founfoundd toto bbee brokenbroken,, signifyingsignifying crystallizatiocrystallizationn iinn a plastiplasticc mediummedium ratherrather ReferenceReferencess thathann formationformation frofromm recrystallizationrecrystallization ooff thethe Bouska,Bouska, et al.,at., 1994. 1994 .Natural Natura lglasses. glasses Academia,. Academia Prague, Pragu e solidsolid obsidian.obsidian. SillimaniteSillimanite isis a high­high- Giibelin,Gubelin, E.,E., anandd KoivulaKoivula,, J.L,J.I., 1992.1992. PhotoatlasFhotoatlas of of inclusions inclusions temperaturtemperaturee polymorppolymorphh ooff A1Al2SiOs whicwhichh isis in gemstones.gemstones. ABC AB CEdition, Edition Zurich, Zuric h consistentconsistent witwithh presencpresencee ooff indiaindialit litee HenHennn u.,U., 1995.1995. Makusanit,Makusanit, einein klarklar durchsichtigerdurchsichtiger ObsidianObsidian postulatedpostulated above.above. ThThee crystacrystall shapeshape ooff thethe ausaus PeruPeru.. Gemmologie, Z. ZVt.. Dt. Gemmo!. Gemmol. Ges., Ges.,44(1), 44(1)25--8 , 25-8 Holzhey, G., 1996. Durchsichtiger Obsidian (Marekanit) thirthirdd kindkind ofof inclusioninclusion correspondscorresponds withwith Holzhey, G., 1996. Durchsichtiger Obsidian (Marekanit) imim PerliPerlitt vonvon Superior,Superior, ArizonaArizona,, USA.USA. Gemmologie, feldsparfeldspar,, anandd tinytiny feldsparsfeldspars areare mentionedmentioned asas Z. Vt.Dt. Gemmol. Ges., Ges., 45(2), 45(2) 83-9, 83- 9 commocommonn inclusionsinclusions inin manymany obsidiansobsidians KoivulaKoivula,, J.I.J.I.,, 1998,1998, personapersonall communicationcommunication

Obsidian from from Chile Chile with with unusual unusual inclusions inclusions Obsidian froJohachidolitm Chile wite h- aunusua new gel m R.Rinclusion. Harding1, J.G. Franciss2, CJ.E. Oldershaw2 and A.H. Rankin3 1. Gemmological Association and Gem Testing Laboratory of Great Britain, Dr Jaroslav Hyrsl1 and Dr Vladimir Zäcek2 27 Greville Street, London EC1N 8TN 2. Department1. Kolin, of Czech Mineralogy, Republic Natural History Museum, London S W7 5BD 2. Czech Geological3. Sc/zoo/ of Survey, Geological Prague, Sciences, Czech RepublicKingston University, Kingston upon Thames, KTC 2EE

ABSTRACT: A new type of transparent slightly yellowish obsidian from northern ChilABSTRACT:e is describe Ad palande ityellos chemicaw mixed-cul compositiot gemstonn is egiven of 14.0. 2 ct has been The obsidian hasidentifie a refractivd aes inde the xrar ofe 1.54 borate0 an,d johachidolit a specific gravite (CaAlBy of 2.36307); and is the first it contains threrecordee typeds geomf distincof this tspecies well-crystallize. Its gemmologicad inclusionl properties - s are described hexagonal very anstrongld arey broadlpleochroiy consistenc columnat witr crystalh the sdat thougha publishet to bde for the original indialite (high-temperaturmineral froe mpolymorp Korea exceph of cordierite)t that the, birefringencelongated striatee of thd e gem (0.007) is rods of sillimanitsmallee and rtin anyd parallelepiped its fluorescenst opropertief probablse ma feldspary differ. . The Raman spectrum of johachidolite is presented. Keywords: Chile, inclusions, indialite, obsidian, sillimanite Keywords: borate, johachidolite, new gem variety, Raman spectrum

Introduction owner. One faceted obsidian is completely Introduction transparent and Figuretwo ar 1:e slightlJohachidolitey milky,, 14.02their ct. Photograph by 324 ransparent natural glasses, with the colour being F.slightl Greenaway.y yellowish . The 321 composition of obsidiann the ,advic are eknow of nC.R . refractivCavey, e thindee x of 1.540 is at the higher limit Tfrom many placeownes throughour of a palet yellothe w cufotr gemstonnatural obsidianse , and the specific gravity world but, unlesOs theycam are to fth attractive GAGTeL in Spring 1998 is 2.36. All three pieces of rough show fine colour and appearanceto have th,e stonare e noidentifiet verdy (Figurdarke layers1). Th,e rarel y curved, indicating fluidal interesting for thresulte gemmologiss from RI tan odr foSGr measurementthe structures an. Theid r surfaces are dull, probably as trade. The new materiafrom spectruml from norther, fluorescencn Chile e a anresuld tfilte of r wind erosion. All stones stay examination were inconclusive and an is a nice exception especially due to its bright during rotation in the polariscope due electron probe microanalysis (EPMA) at the wonderful interior with a variety of to the abundant anisotropic inclusions; Natural History Museum was suggested. inclusions. obsidian itself is isotropic. The chemical The analysis at the Museum indicated the Descriptiopresence of nC a and Al but significantly the total was low, which suggested Figurethe presenc 1: Facetede obsidians, 17 mm and 14 mm long. Photograph by J. Hyrsl Three cut stoneofs abetween elemenn 7.1t 3o anr delement 12.90 cst of low atomic and three roughnumbe piecesr betwee(less ntha 5n an sodium)d 8 g . The most were bought inpromisin Brazil gin lin199e7 anof d enquir1998 y was then respectively by investigatiothe first authon by rX-ra andy diffractiothey n and since reputedly came thifrosm mean the Atacamt scrapina deserg a tminut in e amount of northern Chile (sepowdee Figurer fro 1).m Th the elocalit girdly eis of the stone, probably correctpermissio, becausen similahad rto obsidiabe obtainen d from the comes from a nearbownery regio. Thins inwa Pers udul anyd hagranteds ; an X-ray been called 'macusanitepowder ' diffractioafter the nregiona patterl n was then name (see later).obtaine Veryd littlande thiobsidias proven dwa tso be a clear and found and onlconvinciny a fegw matc pieceh wits h werthe estandar d pattern transparent enougof h thtoe b erar cuet accordinborate gmineral to the , johachidolite (Powder Diffraction File number 29-280).

© Gemmological Associatio© Gemmologican and Gelm Associatio Testing Laboratorn and Geym o Testinf Greagt BritaiLaboratorn y of Great Britain ISSN: 1355-4565 ISSN: 1355—4565 BRITISH MUSEUM (MINF.IRA L DEPT.l

Reg . No .r.q.S'.O., .. J.&.1t JohachidoliteJohachidolite - thethe mineralmineral JohachidoliteJohachidolite waswas firstfirst describeddescribed byby IwaseIwase ..OHilC. H..I.D.Q.L1T.. E:...... andand SaitoSaito (1942)(1942) fromfrom thethe typetype localitylocality inin thethe (:\" o .. c.~.Le ""t p.,.t"d-c.~ pI .... ,,;',:. JohachidoJohachido DistrictDistrict,, KisshuKisshu County,County, KankyoKankyo ,,"","'.,< HoduHodu Prefecture,Prefecture, NorthNorth KoreaKorea (Figure 2)2).. MooreMoore andand ArakiAraki (1972)(1972) solvedsolved thethe structurestructure ofof a crystalcrystal (in(in ththee NationalNational MuseumMuseum ofof .... TQ.b.Q..""'hi ..clQ.~ ...... NaturaNaturall History,History, Washington)Washington) fromfrom thethe samesame localitylocality andand thisthis ledled themthem toto assignassign a formulaformula l<.et1k.y.Qh.o.~.v~~)~ .. Ko..r} ofof CaAlBp7CaAlB307 toto johachidolitejohachidolite,, i.e.i.e. withouwithoutt thethe (Dr. & . Sw,b.e<) componentscomponents H,H, F andand NaNa ofof thethe originaloriginal 11 formulaformula ofof IwaseIwase andand SaitoSaito (1942)(1942) whichwhich MooreMoore anandd ArakiAraki (1972)(1972) attributedattributed toto impurities.impurities. AristarainAristarain andand ErdErd (1977)(1977) reviewedreviewed thethe historhistoryy ofof investigationinvestigation intointo johachidolitejohachidolite,, furtherfurther refinedrefined thethe datadata onon itsits crystallographiccrystallographic propertiepropertiess and,and, withwith thethe approvalapproval ofof thethe IMAIMA CommissionCommission onon NewNew MineralsMinerals andand MineralMineral NamesNames,, confirmedconfirmed itsits composition as CaAlB307. Until now, the composition as CaAlB30 T Until now, the onlyonly reportedreported occurrenceoccurrence ofof johachidolitjohachidolitee isis inin NorthNorth KoreaKorea wherewhere itit isis foundfound inin nephelinenepheline veinsveins cuttingcutting metamorphosedmetamorphosed limestone.limestone. InIn specimenspecimen 105479105479 inin thethe NationalNational MuseumMuseum ofof NaturalNatural HistoryHistory Figure 2: Johachidolite occurs occurs as as tiny tiny grainsgrains inin aa 321: (Washington),(Washington), johachidolitjohachidolitee isis associatedassociated small vein crossing the centre of the specimen J which was presented to the Natural HistoryHistory withwith scapolite,scapolite, diopside,diopside, albitealbite andand phlogopite (in addition to nepheline) as Museum by Dr G. Switzer of the SmithsonianSmithsonian phlogopite (in addition to nepheline) as Institution in 1950. Details of the specimen are equant anhedral grains up to 1 mm across. It equant anhedral grains up to 1 mm across. It on the museum label andand thethe gemgem johachidolitejohachidolite isis isis colourlesscolourless andand transparenttransparent oror whitishwhitish andand shown for comparison. Photograph by semi-transparent;semi-transparent; undeunderr short-waveshort-wave F. Greenaway.Greenaway. ultravioletultraviolet radiatioradiationn itit showsshows pale-bluepale-blue fluorescencefluorescence andand weaweakk phosphorescence.phosphorescence. diameter)diameter) bbyy 14.3614.36 mmmm (short(short diameter)diameter) byby TheThe rockrock specimenspecimen shownshown inin Figure 2 waswas 8.998.99 mmmm (depth),(depth), andand weighingweighing 14.0214.02 ct.ct. ItIt isis presentedpresented toto thethe BritishBritish MuseumMuseum (Natural(Natural palepale yellowyellow withwith nono detectabledetectable pleochroismpleochroism History)History) bbyy DDrr GG.. SwitzerSwitzer ooff ththee SmithsonianSmithsonian andand displaysdisplays strongstrong whitish-bluewhitish-blue Institution,Institution, Washington,Washington, andand isis presumablypresumably fluorescencefluorescence underunder long-wavelong-wave ultraviolet,ultraviolet, comparablecomparable withwith ththee materialmaterial originallyoriginally weakweak blubluee fluorescencefluorescence underunder shortshort wave,wave, examined.examined. RecentRecent electronelectron microprobemicroprobe workwork andand nnoo phosphorescence.phosphorescence. UndeUnderr thethe ChelseaChelsea onon thisthis specimenspecimen hahass confirmedconfirmed thethe presencepresence ColourColour FilterFilter itit appearsappears yellowish-green.yellowish-green. ofof a veinvein ofof smallsmall grainsgrains ofof johachidolitjohachidolitee inin a RefractiveRefractive indexindex readingsreadings takentaken fromfrom thethe matrimatrixx ofof feldspathoid,feldspathoid, plagioclasplagioclasee feldsparfeldspar tabletable facetfacet onon RayneRaynerr DialdeDialdexx andand KrossKruss andand otherother minerals.minerals. refractometersrefractometers givegive thethe followingfollowing results:results: a 1.717,1.717, ~(3 1.7201.720 Y71.724, 1.724 ,giving giving aa birefringence birefringence PropertiesProperties ofof gem-qualitygem-quality ofof 0.007.0.007. SpecificSpecific gravitygravity measurementsmeasurements werewere carriedcarried outout usingusing thethe hydrostatichydrostatic methodmethod inin johachidolitejohachidolite demineralizeddemineralized waterwater andand yieldedyielded a meanmean SGSG TheThe gemgem johachidolitjohachidolitee hashas a modifiedmodified •ooff 3.45.3.45. brilliant-cutbrilliant-cut crowncrown andand a step-cutstep-cut pavilion,pavilion, ExaminationExamination ofof thethe stonestone throughthrough a measurinmeasuringg approximatelyapproximately 15.8315.83 mmmm (long(long hand-heldhand-held spectroscopespectroscope revealedrevealed nono

Johachidolite - - aa new new gem gem Figure 3: (a) One of two curved planes showing dense pattern of tubular cavities, just beneath thethe tabletable facet. (b) Needle inclusion angled into the stone from a pavilion facet, with reflecting crystals or discs along the length (about 2 mm). Photographs by R.R. Harding.Harding.

distinctivedistinctive absorptionabsorption oror fluorescencefluorescence bands;bands; a SomeSome propertiepropertiess ofof johachidolitjohachidolitee reportedreported UV-visibleUV-visible spectrumspectrum ofof thethe johachidolitjohachidolitee fromfrom byby AristarainAristarain andand ErdErd (1977)(1977) areare comparedcompared thethe PyePye UnicamUnicam PU8800PU8800 spectrophotometerspectrophotometer withwith resultsresults obtainedobtained fromfrom thethe gemgem inin Table 1. I. showedshowed completecomplete absorptionabsorption atat wavelengthswavelengths TwoTwo differencesdifferences worthworth notingnoting areare thethe shortershorter thanthan 350350 nm,nm, a shouldershoulder atat 380380 nmnm andand birefringencbirefringencee valuesvalues andand thethe possiblepossible transmissiontransmission withwith nono significantsignificant absorptionabsorption differencesdifferences inin behavioubehaviourr underunder ultravioletultraviolet bandbandss upup toto 750750 nm.nm. radiation.radiation. TheThe measuredmeasured birefringencbirefringencee ofof thethe UnderUnder lOxlOx magnification,magnification, twotwo feathersfeathers areare gemgem johachidolitjohachidolitee isis halfhalf thatthat reportedreported bbyy bothboth 326326 visiblevisible jusjustt underunder thethe tabletable (see(see Figure 3a) andand IwaseIwase andand SaitoSaito (1942)(1942) andand AristarainAristarain andand ErdErd twotwo needlesneedles occuroccur deepdeep inin thethe pavilionpavilion.. UnderUnder (1977).(1977). InIn thethe papepaperr byby AristarainAristarain andand ErdErd thethe higherhigher magnificationsmagnifications ofof a microscope,microscope, (1977)(1977) itit isis notnot clearclear ifif thethe mineralmineral theythey testedtested moremore needlesneedles areare visiblevisible andand somesome areare fluorescedfluoresced underunder long-wavelong-wave ultraviolet;ultraviolet; thethe accompaniedaccompanied byby a tinytiny discdisc oror tabulartabular crystalcrystal gemgem johachidolitjohachidolitee isis stronglystrongly fluorescentfluorescent atat a highhigh angleangle toto thethe needleneedle (Figure 3b).3b). underunder long-wavelong-wave ultraviolet,ultraviolet, showsshows weakweak

1 2 Refractive indices a 1.712 1.717 Refractive indices Cl 1.712 1.717 1.717 1.720 Pf3 1.717 1.720 1.726 1.724 YY 1.726 1.724 BirefringencBirefringencee 0.010.0144 0.000.0077 OptiOpticc sigsignn positivpositivee positivpositivee SpecifiSpecificc gravitygravity 3.33.377 (meas.(meas.)) 3.43.455 3.43.433 (calc.(calc.)) ColouColourr colourlescolourlesss palpalee yelloyelloww FluorescenceFluorescence:: LWULWUVV nonott reportereportedd stronstrong whitish-bluwhitish-bluee SWUSWUVV palpalee blubluee weaweakk blubluee PhosphorescencPhosphorescencee weaweakk nonnonee Table 1.I. Properties ofof johachidolite derived derived from from 1.1. fromfrom AristarainAristarain andand ErdErd (1977)(1977) 1, the mineral fromfrom North North 2.2. thisthis workwork Korea, and and 2, 2,the the gem gem

J. Gemm., 1998, 26, 5, 324-329324-329 v v v 700 12 Johachidolite 600

500

C 400 £>"iii 400H ~ c 300

200

100

0 800 700 600 500 400 300 200 600 500 200 Wavenumber em-I Wavenumber cm-1

Figure 4: Raman spectrum of johachidolite;johllchidolite; tabletable facet facet perpendicular perpendicular to to the the laser laser beam. beam. Sketch Sketch of of stone stone shows three directions of laser beam (LB) used to obtain spectra. The spectra fromfrom allall threethree directions contained the seven peaks arrowed.arrowed. 3273 27 fluorescencefiuor€srence inin SWUVSWUV (in(in agreementagreement withwith thatthat DiscussionDiscussion ofof thethe mineral),mineral), anandd showsshows nnoo phosphores­phosphores­ cencecence - unlikunlikee thethe mineral.mineral. TheThe appearanceappearance ofof a 1414 ctct cutcut gemstonegemstone ofof a speciesspecies onlyonly knownknown inin naturenature asas colourlesscolourless RamanRaman spectraspectra werweree obtaineobtainedd usingusing a transparentransparentt grainsgrains lessless thanthan I1 nunmm acrossacross waswas a RenishawRenishaw micro-Ramanmicro-Raman 10001000 systemsystem considerableconsiderable surprise,surprise, andand inunediatelyimmediately ledled toto coupledcoupled toto aann AArr ioionn laselaserr (514(514 nm)nm) anandd a questionquestionss aboutabout itsits origin;origin; inin particularparticular initiallyinitially petrologicapetrologicall microscopemicroscope.. TheThe systemsystem waswas asas toto whetherwhether itit waswas naturalnatural oror synthetic.synthetic. operatedoperated inin confocalconfocal modemode withwith ththee laserlaser TheThe stonestone wawass boughtbought inin MyanmarMyanmar asas a beabeamm focusefocusedd aboutabout 50!lm50 ^im belobeloww ththee surfacesurface naturanaturall gemgem butbut ththee speciesspecies isis soso rarerare thathatt thethe ofof thethe stonestone andand operatedoperated atat fulfulll powerpower possibilitpossibilityy thatthat itit hadhad beenbeen introducedintroduced intointo (20 rnW). Scanning times of 60 seconds were (20 mW). Scanning times of 60 seconds were thethe gemgem tradetrade afterafter havinghaving beenbeen growngrown inin a used for each of three spectra obtained from used for each of three spectra obtained from laboratorlaboratoryy hadhad toto bebe investigated.investigated. NaturalNatural differendifferentt orientationsorientations ofof thethe crystal.crystal. andand syntheticsynthetic substancessubstances containingcontaining boronboron Characteristic Raman shifts in wavenumbers Characteristic Raman shifts in wavenumbers werweree recentlyrecently describeddescribed inin anan encyclopaedicencyclopaedic -11 (cm ) are shown in Figure 4. (cm- are shown in volumvolumee editededited byby GrewGrew andand AnovitzAnovitz andand ThThee spectrumspectrum withwith thethe mostmost peakspeaks waswas publishepublishedd byby ththee MineralogicaMineralogicall SocietySociety ofof obtainedobtained withwith thethe laselaserr beabeamm perpendicularperpendicular AmericAmericaa (1996).(1996). InIn thisthis volume,volume, WerdinWerdingg andand toto thethe tabletable facet.facet. SpectraSpectra obtainedobtained fromfrom SchreyerSchreyer (1996)(1996) setset outout toto presenpresentt existingexisting pavilionpavilion facetsfacets neanearr ththee girdlegirdle atat eacheach endend ooff datadata onon experimentalexperimental studiesstudies ofof borosilicatesborosilicates thethe stonestone containedcontained fewerfewer peaks,peaks, bubutt allall andand selectedselected borateboratess andand mademade nono referencereference spectraspectra containecontainedd thethe sevenseven peakspeaks arrowedarrowed toto johachidolitejohachidolite,, presumablypresumably reflectingreflecting thethe inin Figure 4, i.e.i.e. atat 831,831, 664,664, 586,586, 476,476, 373,373, 345345 absenceabsence ofof anyany significantsignificant work.work. AnovitzAnovitz andand andand 283283 cm-l,cm"1, allall ± 2 em-I.cm"1. HemingwayHemingway (]996)(1996) alsoalso presentedpresented a

Jolwchi4oIiteJohachidolite -- aa nm' new gem gem IfIf thethe stonestone isis ofof naturanaturall originorigin andand possiblepossible sourcesourcess areare beingbeing considered,considered, itit mighmightt bebe usefuusefull toto comparecompare itit withwith otherother boratesborates.. Gem-qualityGem-quality examplesexamples ofof naturalnatural boratesborates includeinclude hambergitehambergite [BeZ<0H,[Be2(OH, F)B03]L, rhodiziterhodizite [(K,[(K, Cs)AICs)Al4BeBe/B,4(B, Be\P2s1Be)12028] andand jeremejevite [AI B 0 (OH, F)3 but the best jeremejevite [Al66Bs50151s(OH, F)3L], but the best knownknown isis sinhalitesinhalite [MgAlB041[MgAlBOJ (see(see Figure 5).5). SinhaliteSinhalite ofof gemgem qualityquality comescomes largelylargely iiff notnot exclusivelyexclusively fromfrom SriSri Lanka,Lanka, bubutt oneone crystalcrystal (rough)(rough) waswas foundfound inin BurmaBurma andand broughtbrought toto LondonLondon bbyy A.C.D.A.C.D. PaiPainn (Payne,(Payne, 1958).1958). Non-gem-qualitNon-gem-qualityy sinhalitesinhalite hashas beenbeen foundfound inin botbothh WarrenWarren County,County, NeNeww YorkYork (Schaller(Schaller andand Hildebrand,Hildebrand, 1955),1955), andand HandeniHandeni District,District, TanzaniaTanzania (Bowden(Bowden et a!.,ah, 1969);1969); botbothh occurrencesoccurrences areare inin metamorphosedmetamorphosed limestones,limestones, geologicalgeological contextscontexts veryvery similarsimilar toto thatthat describeddescribed forfor johachidolitejohachidolite.. TheThe occurrenceoccurrence ofof thethe borosilicateborosilicatess tourmaline,tourmaline, kornerupinekornerupine andand danburitedanburite inin oror nearnear ththee MogokMogok gegemm gravelsgravels (Figure 5) togethertogether withwith thethe admittedlyadmittedly rarerare t^^gua Figure 5: Johachidolite (centre right, 14.02 ct) occurrenceoccurrence ofof sinhalitesinhalite suggestssuggests thatthat otherother ff£$M€f with two sinhalites (centre left, brown, 9.84 ct; borateboratess maymay alsoalso bebe presenpresentt atat Mogok.Mogok. InIn thisthis |! and toptop right,right, yellow, 6.25 ct)ct) and twotwo danburitesdanburites 328 context,context, painite,painite, thethe mostmost famousfamous rarerare (bottom right, table cut, 18.85 ct; and top left,left, mineral of all from Burma, has a small round, 13.10 ct). The danburites are fromfrom Mogok,Mogok, mineral of all from Burma, has a small Myanmar, and the sinhalites are probably from contentcontent ofof boronboron inin anan essentiallyessentially aluminatealuminate Sri Lanka. Photograph by F. Greenaway.Greenaway. structure.structure. ThisThis areaarea thereforetherefore couldcould bbee a possiblepossible sourcesource ofof naturalnatural gemgem johachidolite.johachidolite. summarysummary (in(in theirtheir TableTable 6)6) listinglisting referencesreferences InIn a historicalhistorical context,context, thethe presentpresent toto knownknown experimentalexperimental datadata foforr mineralsminerals investigationinvestigation intointo johachidolitjohachidolitee hashas manymany containingcontaining boronboron,, andand althoughalthough johachidolitejohachidolite similaritiessimilarities withwith thethe discoverdiscoveryy ofof a borate,borate, isis inin thethe listlist,, thethe adjacentadjacent columncolumn forfor alreadyalready cutcut asas a gem,gem, somesome fiftyfifty yearsyears agoago referencesreferences toto anyany experimentalexperimental worworkk onon whewhenn collaborationcollaboration betweenbetween AndersonAnderson andand johachidolitjohachidolitee isis blank.blank. PaynePayne ofof thethe GemGem TestingTesting LaboratoryLaboratory andand CrystalCrystal growinggrowing activitiesactivities areare extensiveextensive ClaringbullClaringbull andand HeyHey ofof thethe NaturalNatural HistoryHistory andand variedvaried inin ththee formerformer USSR,USSR, Thailand,Thailand, thethe MuseumMuseum ledled toto thethe recognitionrecognition andand P.R.P.R. ofof ChinaChina andand otherother countries.countries. SoSo searchessearches descriptiondescription ofof thethe neneww mineraminerall sinhalitesinhalite werweree mademade forfor referencesreferences toto johachidolitejohachidolite (Claringbull(Claringbull andand Hey,Hey, 1952).1952). andand toto CaAICaAl boratesborates inin ththee indexesindexes ofof thethe Journal of Crystal Growth and of Chemical Journal of Crystal Growth and of Chemical Conclusion Abstracts fromfrom 1990-97.1990-97. TheseThese alsoalso provedproved fruitless,fruitless, andand provisionallyprovisionally oneone mustmust ThisThis isis thethe firstfirst reportedreported occurrenceoccurrence ooff concludeconclude thatthat CaAICaAl borateborate isis eithereither ofof littlelittle gem-qualitygem-quality johachidolitejohachidolite.. NoNo evidenceevidence ooff interestinterest ttoo ththee materialsmaterials researchersresearchers or,or, ifif itit isis anyany sourcessources ofof syntheticsynthetic CaAICaAl boratesborates couldcould ofof interest,interest, thethe resultresultss areare nonott beingbeing bebe founfoundd inin currentcurrent literatureliterature andand thethe stonestone isis publishedpublished.. Anyway,Anyway, nono sourcesource forfor syntheticsynthetic probablprobablyy natural,natural, withwith a possiblepossible sourcesource inin johachidolitjohachidolitee waswas indicated.indicated. thethe MogokMogok areaarea ofof Myanmar.Myanmar.

J./. Gemm., 1998, 26, 5, 324--329324-329 AcknowledgementsAcknowledgements Aristarain,Aristarain, L.F,L.F., andand Erd,Erd, R.C,R.C., 1977.1977. JohachidoliteJohachidolite redefined:redefined: a calciumcalcium aluntiniumaluminium borate.borate. Amer. Min., 62,62,327- 327-99 WeWe wouldwould likelike toto thankthank F.F. GreenawayGreenaway forfor Bowden,Bowden, P.,P., VonVon Knorring,Knorring, 0.,O., andand Bartholomew,Bartholomew, R.W.,R.W., photographsphotographs ofof thethe gemsgems andand MuseumMuseum 1969.1969. SinhaliteSinhalite andand serendibiteserendibite fromfrom Tanzania.Tanzania. specimen,specimen, andand J.J. SprattSpratt forfor thethe electronelectron MineralMineral. Mag., 37(285),37(285), 145--{j145-6 microprobemicroprobe analyses.analyses. A.I.A.I. Castro,Castro, Claringbull,Claringbull, G.F,G.F., andand Hey,Hey, M.H.,M.H., 1952.1952. SinhaliteSinhalite (MgAIBO.),(MgAlB04), a newnew mineral.mineral. Mineral. Mag., 29(217),29(217), S.J.S.J. KennedyKennedy andand T.T. LodgeLodge atat thethe GAGTGAGTLL 841-9841-9 GemGem TestingTesting LaboratoryLaboratory areare thankedthanked forfor theirtheir Grew,Grew, E.s.,E.S., andand Anovitz,Anovitz, L.M.,L.M., 1996.1996. Boron:Boron: mineralogy,mineralogy, workwork onon thethe gem,gem, andand M.J.M.J. O'DonoghueO'Donoghue andand petrologypetrology andand geochemistry.geochemistry. Mineral. Soc. Am: Reviews DrDr ChenChen ChangkangChangkang (Clarendon(Clarendon Laboratory,Laboratory, in Mineralogy. 33.33. WashingtonWashington Iwase,Iwase, E.,E., andand Saito,Saito, N.N.,, 1942.1942. JohachidoliteJohachidolite - a newnew Oxford)Oxford) providedprovided usefuluseful adviceadvice inin searchingsearching mineralmineral ofof hydroushydrous fluoboratefluoborate ofof sodium,sodium, calciumcalcium andand thethe literature.literature. FinallyFinally wewe wouldwould likelike toto thankthank aluminium.aluminium. ScientificScientific PapersPapers Ins.Ins. Physical Chemical thethe ownerowner ofof thethe stonestone forfor permissionpermission toto Research, Tokyo, 39,39,300- 300-44 examineexamine itit inin detail.detail. Moore,Moore, P.B.,P.B., andand Araki,Araki, T.,T., 1972.1972. Johachidolite,Johachidolite, CaAICaAl ), (B33007), a borateborate withwith a ververyy densedense atomicatomic struchlre.structure. Nature Phys. Sci.,Sci, 240,240, 63-563-5 ReferencesReferences Payne,Payne, CJ.,C.J., 1958.1958. A crystalcrystal ofof sinhalitesinhalite fromfrom Mogok,Mogok, Burma.Burma. Mineral. Mag., 3131 (242),(242), 978-9978-9 Anovitz,Anovitz, L.M.,L.M., andand Hemingway,Hemingway, B.S.B.s.,, 1996.1996. Schaller,Schaller, W.T.,W.T., andand Hildebrand,Hildebrand, FA.,F.A., 1955.1955. A secondsecond occur­occur­ ThermodynamicsThermodynamics ofof boroboronn minerals:minerals: summarysummary ooff rencerence ofof thethe mineralmineral sinhalite.sinhalite. Amer. Mineral.,Mineral, 40,40,453- 453-77 struchlral,structural, volumetricvolumetric andand thermochemicalthermochemical data.data. In: Werding,Wending, G.,G., andand Schreyer,Schreyer, W.,W, 1996.1996. ExperimentalExperimental shldiesstudies Grew,Grew, E.S.,E.S., andand Anovitz,Anovitz, L.M.L.M. (eds),(eds), Boron:Boron: onon borosilicatesborosilicates andand selectedselected boratesborates.. In:In: Grew,Grew, E.s.,E.S., andand mineralogy,mineralogy, petrologypetrology andand geochemistry.geochemistry. Mineral. Soc. Anovitz,Anovitz, L.M.L.M. (eds).(eds). Boron:Boron: mineralogy,mineralogy, petrologpetrologyy andand Am., Washington.Washington. 181-261181-261 geochemistry.geochemistry. Mineral. Soc. Am.,Am., Washington,Washington, 117--{j3117-63

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Diamonds Synthetics and Simulants

Recovery and refining of precious metals. Beautifully produced and illustrated guide to the [Third editionGem] s and Minerals 'new' [i.e., relocated] Deutsche Edelsteinmuseum at Idar- Oberstein. Much of the text and illustrative matter is close C. W. AMMEN, 1997. Chapman and Hall, New York, pp xi, to that used for a description of the museum published in 441, softcover. £37.00. ISBN 0 412 72060 4. Der Aufschluss fairly recently and an advertisement for the The first edition has become known as the 'Precious publisherjewellery smanufacturers of Aufschlus; 7s0 appearper censt boyn weighthe bact andk 3cover5 per. metal bible7 and anyone connected with the manufacture, Diamonds Howevercent (wholesale, an inser) valut givee osf adiamond plan of sth ien nethwe worlbuildind arge ancudt testing or evaluation of jewellery should read this text arrangementhere. From tth oef latitse exhibit sixtiess thane dmarke this its hadates expanded 1996. d by 82 whicGemh approximatenews. s to a metal testing manual with copious fold by polished weight and 249 fold by polished (whole- After a history of the museum and of the gemstone explanations of how the testing results are obtained. The sale) value. This expansion has been due to the exploitation M.L. JOHNSON AND J.I. KOIVULA. Gems & Gemology, 34(1), industry in the Idar-Oberstein area, the book goes on to book opens with a very useful section on general chemistry of the large diamond deposits in Russia, Botswana and 1998,50-62,23 coloured illus. describe the nature and testing of gem specimens before before proceeding to the chemistry of the precious (and Australia, especially the Argyle mine in Western Australia, covering the major species in chemical order, the otherDiamon) metalsd. Recovercrystalsy i nan varioud refinins shapeg methods frosm ar eRussi describea andd which produces large quantities of small low quality customary arrangement for a cabinet of minerals. Both aChint considerabla were oen lengthdispla, yan adt ththee 199whol8 eTucso text ni sTrad presentee Faird. material. In the future India will have difficulties main- major and uncommon species are introduced and a great lucidly in such a way that the reader can assimilate a gooJJd. taining its position as the largest supplier of polished stones many are illustrated by top class colour photographs. deal of serious metallurgy and at the same time find out in the world due to the diminishing availability of small Organic and man-made materials are reviewed before how to regard the precious metals that may turn up needing stones. There are no new major mines in an advanced stage Zur Vulkanologie von diamantführenden accounts of gemstone fashioning, naming and use. There to be tested. Appendices give a list of the naturally-occurring of development that could produce the volume of gem Kimberlit- und Lamproit-Diatremen. is a very short bibliography, a table of synthetic materials chemical elements with their atomic weights and numbers, rough needed to replace the Argyle mine when it becomes and growers with the date of their first appearance and a aV .lis t LORENZof some. of Gemmologiethe metallic salt(Zeitschrifts and thei r contentder sDeutschen and one exhausted within the next six years. The implications for table of recently discovered gem species and varieties. An of thGemmologischene best glossaries I Gesellschaft),have seen fo r 47(1)some, time1998. , 5-30, 11 India are of unemployment but this might be alleviated by photographs, 2 diagrams, bibl. index concludes the book. M.O'D. While intended for a wide readership, students the cutting and polishing of synthetic diamonds. J J. beginninThe gvulcanolog a course yin ometallurgf diamondiferouy in particulas kimberlitr wilel finandd lamproite diatremes and dykes is considered in the light Gem minerals of Victoria. 330334 many uses for the book and the price is very reasonable Diamond prospecting in Finland - a review. foofr sao detailecomprehensivd modeel ao coveragf phreatomagmatie of the fieldc .formatio M.O'Dn o.f W. D. BIRCH AND D. A. HENRY, 1997. (Mineralogical Society M. TYNI. In Mineral Deposits, ed. H. Papunen (Balkema, maar-diatreme volcanoes. Maars and the underlying of Victoria: Special Publication No. 4), Melbourne, diatremes form when magma rises in dykes and contacts Rotterdam), 1997, 789-91. Handbook of mineralogy. Vol III: halides, pp 121. A$29.95 (plus A$14.00 economy air post). groundwater resulting in thermohydraulic explosions. To date, 24 kimberlites and related deposits have been hydroxides, oxides. ISBN 0 959 4573 3 X. The magma with the surrounding country rocks is discovered in Finland, of which 16 are diamondiferous. Although the State of Victoria is not the richest in J.Wfragmented. ANTHONY, th, eR.A groundwate. BIDEAUX, rK.W vaporize. BLADdH ANandD thenM.C., R.A.H. Australia for gemstones, nevertheless it contains a becausNICHOLSe of th, e1997 expansio. Mineran olf Datthe asteam Publishing, the fragmente, Tucsond, considerable range of collectable gems. The aim of this materialpp ixs, are62 ejecte8 Hardcoverd at the surfac. Price ane d causon e applicationthe collapse. well-illustrate[Examinatiodn booon kcolourin is not tgo obef diamonda locality sguideboo by k of thISBe surroundinN 0 962209g7 2rocks 4. ; at the earth's surface it forms a (thougprotonh beaeachm o firradiation. the more importan] t localities for each collapse crater, a maar. The article explains the Three down and two to go! I refer of course to the species is listed and discussed), but rather to provide hydrogeological conditions necessary for the formation of (Japanese with English abstract.) progress of this magnificent series which gives single assistance with the identification of the gem minerals. pagkimberlite coverage ande lamproitto each e validatediatremesd . mineral species anE.Sd. I. UMEDA AND K. IIDA. Journal of the Gemmological Society of which has been exceptionally well-received by the AfteJapanr, a21n ,introductor 1996, 15-19y. chapter outlining the discovery of gem deposits, those such as diamonds, sapphires, mineralogical community. The first volume covered A 2.378 ct colourless diamond was first irradiated by The rise to prominence of the modern diamond zircons and olivine which are typically associated with elements, sulphides, sulphosalts and some less important high energy electron beam using a linear accelerator, which cutting industry in India. basic volcanic rocks are described. Small diamonds have classes and the second, in two volumes gave (at last!) an produced homogeneous green colour, and subsequently been found in alluvial deposits, most being discovered by up-to-dateM. SEVDERMISH surve, A.Ry o. fMICIA the Ksilicates AND A.A. Th. LEVINSONe remainin. Gemsg tw o& annealed. The stone became homogeneously yellow, which accident during treatment of wash dirt for gold and tin volumeGemologys are , schedule34(1), 1998d t,o 4-23cove, r1 5arsenates illus. in, colouphosphatesr and 2, was then irradiated by 18MeV proton beam using a recovery; no commercial deposits have been found and uranatetabless .an d vanadates (one volume) and borates, cyclotron to the culet through a tj> 3 mm metallic collimeter. the primary source of the diamonds remains unknown. carbonatesOver th, esulphate last thirtsy an tod fort smaly yearl groups Indis awhic has hbecom havee noonte The stone became bi-colour; surrounding the culet is green, Sapphires are of widespread occurrence as waterworn beeof thn edeal majot witr centreh alreadys for .th e cutting of diamonds, and is the the table and the girdle are yellow. The stone exhibits an crystals in present-day streams and older gravels; blue is sixth most important diamond market in the world. India umbrella mark around the culet, whereas green diamonds Gemmologists will find the present volume the dominant ^olour, but purple, yellow and brown specializes in cutting low quality small diamonds often less produced by irradiation by high energy electron beam do interesting for the information given on oxides alone. A varieties are found. Pale rubies also occur but are rarer than 7 points and these are mostly exported to foreign not show such a mark. I.S. complete set of the Handbook should last a long time even and smaller than sapphires. Rounded grains of reddish though new species are arriving at the rate of around one brown to near colourless zicon are also found in stream a week. M.O'D. gravels at numerous localities. The primary sources of the Abstractorsapphires s and zircons are thought to be basalts and Führer durch das Deutsche Edelsteinmuseum. volcani-sedimentary rocks. Olivines and anorthoclase R.A. Howie R.A.H. M. O'Donoghue M.O'D. I. Sunagawa I.S. H. BANK, 1996. The Museum, Idar-Oberstein, Germany, occur in xenoliths and megacrysts in lava flows of the J. Johnson J.J. E. Stern E.S. pp 128, illustrated in colour, softcover. Price on Newer Volcanics in the W of the state; scoria cones have application. For further information on many of the topics yieldereferredd olivin to, consule fashionet Mineralogicald to give peridoAbstractst < 8 mm in size.

© Gemmological Association and Gem Testing Laboratory of Great Britain J. Gemm., 1998ISSN, 26,: 5,1355-456334-3395 Gems and Minerals FeueropalFeueropal vonvon OpalOpal Butte,Butte, Oregon,Oregon, USA.USA. G.G. HOLZHEY. Gemmologie (Z(Zeitschrifteitschrift der DeutDeutschenschen Gemmologischen GGesellschaft),esel/schaft), 46,, 19919977,, 161-8,, 1010 IridescentIridescent andraditeandradite garnetgarnet fromfrom thethe SierraSierra photographs, 3 tabltableses,, 1 graph, bib!.bibl. MadreMadre Mountains,Mountains, Sonora,Sonora, Mexico.Mexico. ThisThis occurrenceoccurrence hashas beebeenn knownknown asas Peter'sPeter's ButteButte inin M.A.M.A. BADARBADAR ANDAND M.M. AKIZUKI.AKIZUKI. Neues Jahrbuch fiir Neues Jahrbuch fiir thethe BlueBlue MountainsMountains northnorth easteast ofof OregonOregon sincesince 1889,, butbut Mineralogie Monatschefte, 12,1998,529-39.12,1998, 529-39. hashas onlyonly beenbeen workedworked intenintensivelsivelyy sincesince 1986.1986. TheThe Iridescence inin andraditeandradite fromfrom thethe SierraSierra MadreMadre specimensspecimens occuroccur withinwithin concrconcretion-liketion-likee sphericalspherical masses,masses, Mountains,Mountains, Sonora,Sonora, Mexico,Mexico, waswas examinedexamined byby opopticatical whichwhich carrycarry fillingsfillings ofof firefire andand otherother opals.opals. TheThe firefire opalopal isis microscopy, eelectrolectronn microprobemicroprobe analysis,analysis, back-scatteredback-scattered anan arrangementarrangement ofof silicasilica sphesphereress ofof differentdifferent diameterdiameter upup electronelectron imagimagee andand single-crystalsingle-crystal X-rayX-ray diffraction.diffraction. The toto 250250 nmnm withwith a highhigh cacalciulciumm content.content. RIRI 1.431,1.431, SGSG 2.05.2.05. iridescenceiridescence isis causedcaused bbyy cyclicallycyclically stratifiedstratified growthgrowth lamellaelamellae SomeSome inclusionsinclusions seemseem ttoo bbee ofof oorganirganicc (vegetable?)(vegetable?) matter.matter. inin the {211}{211} andand {110}{110} sectorssectors withwith chemicalchemical contentcontent EE.S.S.. And79-And94.• A marked contrast between adjacent lamellae And,.;-And94 A marked contrast between adjacent lamellae arisesarises fromfrom differingdiffering refractiverefractive indicesindices andand givesgives a sourcesource ofof [Study on the mechanism of formation of 'circle iridescence.. TheThe garnetgarnet waswas founfoundd ttoo containcontain isotropicisotropic andand [Study on the mechanism of formation of 'circle aniSOtropicanisotropic (triclinic)(triclinic) zones.zones. M.O'D.M.O'D. pearlspearls'' -- anan approachapproach fromfrom thethe nacreous.nacreous, structure.)structure.] (Japanese(Japanese witwithh EnglisEnglishh abstract.abstract.)) A corundum-quartzcorundum-quartz assemblageassemblage inin alteredaltered EE.. ITOITO.. Journal of the GGemmologicalemmological Society of Japan, 21,21,1996 1996,, volcanivolcanicc rocksrocks,, BonBondd RangeRange,, TasmaniaTasmania.. 33-44.33^4. R.S.R.S. BOTTRILLBOTIRILL.. Mineralogical Magazine, 62(3),199862(3), 1998,325-32., 325-32. PearlPearlss showinshowingg circumferentiacircumferentiall ditcheditchess oror depressionsdepressions ThisThis unusuaunusuall assemblagassemblagee occursoccurs inin a hydrothermhydrothermallallyy araree calledcalled circlecircle pearlspearls,, anandd araree ofteoftenn encountereencounteredd amongamong alteredaltered CambrianCambrian quartzquartz porphyryporphyry;; ththee quartquartzz andand cultureculturedd blacblackk pearlspearls.. OpticaOpticall anandd SEMSEM observationobservationss werewere corunducorundumm areare iinn mutuamutuall contactcontact,, iinn associationassociation withwith madmadee oonn ththee internainternall structuresstructures ooff ththee nacreounacreouss layerlayer ooff andalusiteandalusite,, pyrophyllitepyrophyllite,, diaspore,diaspore, etc.etc. ThiThiss metastablemetastable circlcirclee pearlpearlss ofof variouvariouss types, asas welwelll asas flaflatt pearlpearlss formedformed assemblagassemblagee apparentlapparentlyy resulteresultedd frofromm advancedadvanced argillicargillic oonn flaflatt shapshapee nucleusnucleus,, twitwinn pearlpearlss formeformedd onon twtwoo nuclei.nuclei. alteratioalterationn aatt moderatmoderatee T anandd P,P, followefollowedd by rapidrapid SectionalSectional coloucolourr distributiondistribution,, stagstagee ooff initiatioinitiationn ooff circles,circles, depressurizatiodepressurizationn accompaaccompanyinnyingg boilinboilingg ofof hydrhydrothermaothermal deviatiodeviationn ooff circlecircless frofromm symmetrysymmetry,, ththee degreedegree ooff granite-derivegranite-derivedd fluidsfluids.. ThiThiss corunducorundumm appearappearss ttoo bebe continuatiocontinuationn ooff aragonitearagonite layerslayers,, thicknesthicknesss anandd numbenumberr ooff unrelateunrelatedd to ththee sapphiresapphiress founfoundd iinn placeplacerr depositdepositss inin aragonitaragonitee layerlayerss aatt depressedepressedd anandd elevateelevatedd portionportionss,, 331 TasmaniaTasmania.. R.A.H.R.A.H. comparisocomparisonn ooff nacreounacreouss structurestructuress betweebetweenn twitwinn anandd flatflat pearlspearls,, anandd circlcirclee twitwinn anandd flaflatt pearlpearlss werweree investigatedinvestigated.. TwTwoo possiblpossiblee mechanismss araree proposeproposedd foforr ththee origioriginn ooff A re-examinatiore-examinationn ofof ththee turquoisturquoisee groupgroup:: thethe circlcirclee pearlspearls;; ononee assumeassumess wrinklewrinkless formeformedd oonn pearpearll sacsac mineraminerall aheyliteaheylite,, phaneritphaneritee (redefined),(redefined), duduee ttoo illnesillnesss ooff mothemotherr pearlpearlss or externaexternall stressstress,, anandd thethe turquoisturquoisee anandd coeruleolactite.coeruleolactite. otheotherr assumeassumess rotatiorotationn ooff ththee nucleunucleuss iinn ththee pearpearll sacsac.. I.S1.5.. E.EE.E.. FOORFOORDD ANANDD J.EJ.E.. TAGGARTTAGGART,, JRJR.. MineralogicalMineralogical MagazineMagazine,, 62(1),,1998,91 1998, 91-111-111.. GeGemm news.news. ThThee turquoisturqUOisee grougroupp hahass ththee generagenerall formulaformula M.LM.L.. JOHNSON ANANDD J.IJ.I.. KOIVULAKOMJLA.. GemsGems & Gemology, 34(1), AAD-I0_1 B.(PO,)4-,(P0B6(PO4)4_;c(PO3OH)30H)/OH).o4HP,;c(OH)8»4H2O, wherwheree x = 0-2,, andand hahass sisixx membersmembers:: planeriteplanerite,, turquoiseturquoise,, faustitefaustite,, ahaheyliteeylite,, 1998, , 50—6250-62,23, 23 illusillus.. iinn colour.. chalcosideritchalcosideritee and aann unnameunnamedd FeFe'+-Fe'+2+-Fe3+ analogue.. The ChiastolitChiastolitee spherespheress frofromm ChinChinaa werweree oonn offeofferr aatt ththee existencexistence ooff 'coeruleolactite'coeruleolactite'' iiss doubtful;; planeritplaneritee iiss 19919988 TucsoTucsonn Trade FairFair.. CoraCorall witwithh a blubluee sheesheenn anandd horhornn revalidaterevalidatedd aass a speciespeciess characterizecharacterizedd bbyy a dominantdominant liklikee appearancappearancee hahass beebeenn founfoundd iinn ththee oceaoceann ooff AlaskAlaskaa aatt A-sitA-sitee vacancyvacancy;; aheylitaheylitee iiss establisheestablishedd aass a neneww membememberr ooff depthdepthss ooff 303000 m oorr moremore.. A facetefacetedd corundumcorundum,, reportedlyreportedly ththee grougroupp characterizecharacterizedd bbyy havinhavingg FeFe'2+ dominandominantt iinn ththee frofromm Vietnam,, gavgavee risrise tto a nomenclaturnomenclaturee probleproblemm aass iitt A-siteA-site.. ChemicaChemicall analyseanalysess ooff 1155 purpuree samplesampless ooff wawass rubrubyy ononee enendd anandd blubluee sapphirsapphiree aat'thet "the otheotherr endend.. microcrystallinmicrocrystallinee planeriteplanerite,, turquoisturquoisee anandd aheylitaheylitee showshow SampleSampless ooff emeralemeraldd frofromm a neneww deposidepositt iinn TocantinTocantinss StateState,, thathatt ^.;; twtwoo ooff ththee (P0(PO,)4) groupgroupss araree protonateprotonatedd (P0(POPH)3OH) iinn BrazilBrazil,, werweree darkedarkerr thathann mosmostt ColombiaColombiann emeraldemeraldss andand planerite;; completcompletee solisolidd solutiosolutionn existexistss betweebetweenn planeritplaneritee showeshowedd evidencevidencee ooff claritclarityy enhancementenhancement.. YellowisYellowishh ttoo anandd turquoiseturquoise.. MosMostt samplesampless ooff 'turquoise'turquoise'' araree cationcation­- reddish-orangreddish-orangee spessartinspessartinee garnetgarnetss frofromm northernnorthern deficiendeficientt oorr araree planeriteplanerite.. TherTheree araree foufourr moleculemoleculess ooff MadagascaMadagascarr araree ooff a larglargee sizsizee anandd unusuaunusuall cuts.. A newnew waterwater.. PlaneritePlanerite,, ideallideallyy DAl.(P6(P0O,),(P0,0H)4)2(P03OH)2,(OH).(OH)8o4HP«4H20,, deposidepositt frofromm NortherNorthernn MadagascaMadagascarr iiss producingproducing iiss white,, palpalee blubluee oorr palpalee green,, anandd occuroccurss aass mamillarmamillaryy yellowish-browyellowish-brownn sphenessphenes,, witwithh somsomee crystalcrystalss uupp ttoo 2299 ctct,, botryoidabotryoidall crustcrustss aass mucmuchh aass severaseverall mmmm thickthick;; iitt mamayy alsalsoo mucmuchh ooff ththee materiamateriall possiblpossiblyy containcontainss chromiuchromiumm anandd is occuoccurr massivemassive,, microcrystallinemicrocrystalline,, typicalltypicallyy witwithh crystalscrystals reredd whewhenn vieweviewedd througthroughh a ChelseChelseaa filterfilter.. SpineSpinell frofromm ththee 3 2-A2-4 \im,11m, lustrlustree chalkchalkyy ttoo earthyearthy,, H 55,, D 2.62.688 g/cmg/ cm3,, meameann LuLucc YeYenn areareaa iinn VietnaVietnamm iiss nonoww availablavailablee anandd iiss mineminedd aass 2+ RI ~ 1.60. Aheylite, ideally Fe Al6(P04)4(OH)8«4H0 20, is a bi-product of ruby mining. Parti-coloured faceted RI - 1.60. Aheylite, ideally Fe'+AI6(PO,l.(OH)s 4HP, is a bi-product of ruby mining. Parti-coloured faceted palpalee blubluee oorr greengreen,, anandd occuroccurss aass isolateisolatedd crystalcrystalss anandd liddicoatitliddicoatitee tourmalintourmalinee frofromm MadagascaMadagascarr hahass limitelimitedd ususee hemisphericahemisphericall aggregataggregatee ooff crystalcrystalss thathatt averagaveragee 33 [i!-lInm iinn iinn jewellerjewelleryy aass thetheyy tentendd ttoo havee aa muddmuddyy appearancappearancee iinn maximumaximumm dimensiondimension;; porcellanous-subvitreouporcellanous-subvitreouss lustrelustre,, ththee finishefinishedd stonestone.. TransparenTransparentt anandd uniforuniformm colourecolouredd 3 3 meameann RRI-1.63,I ~ 1.63, biaxiabiaxiall (+)(+),, D 2.82.844 g/cmg/cm. • R.A.HR.A.H.. greegreenn tourmalinetourmaliness frofromm NamibiNamibiaa werweree oonn showshow.. J.JJ.J..

AbstractsAbstracts DiopsideDiopside inclusionsinclusions inin ArizonaArizona pyropepyrope identi­identi­ classifiedclassified intointo anisotropicanisotropic columnarcolumnar andand isotropicisotropic fiedfied byby RamanRaman analysis.analysis. massivemassive (opal-CTM)M ) types;types; bothboth texturestextures consistconsist ofof thinthin andand platyplaty crystalscrystals showingshowing twotwo widewide {I01}{101} facesfaces ofof lowlow J.I.J.I. KOIVULA.KOIVULA. Gemmologie IZeitschrift(Zeitschrift der DeutschenDeutschen cristobalite.cristobalite. ImagesImages fromfrom HRTEMHRTEM showshow thatthat ththee Gemmologischen Gesel/schaft),Gesellschaft), 47(1),47(1), 1998,1998, 39-44,39-44, 4 cristobalitecristobalite structurestructure isis thethe fundamentalfundamental componentcomponent ooff photographsphotographs,, 2 graphs,graphs, bib!.bibl. volcanic-typevolcanic-type opal-CT,opal-CT, andand thatthat manymany stackingstacking faultsfaults TheThe authorauthor describesdescribes ththee identificationidentification ofof brightbright greengreen occuroccur atat randomrandom inin thethe structure.structure. ColumnsColumns areare producedproduced diopsidediopside inclusionsinclusions inin pyropepyrope garnetsgarnets fromfrom ArizonaArizona bbyy byby paralleparallell growthgrowth ofof platyplaty crystals;crystals; opal-CTM anandd meansmeans ofof RamanRaman laserlaser microspectrometry.microspectrometry. TheThe RamanRaman lepispherelepispheress consistconsist ofof criss-crossingcriss-crossing aggregatesaggregates ofof blades;blades; spectrum of a completely enclosed inclusion was spectrum of a completely enclosed inclusion was eacheach bladeblade consistsconsists ofof -~ paralleparallell aggregatesaggregates ofof platyplaty comparedcompared toto somesome obtainedobtained fromfrom surface-exposedsurface-exposed crystals.crystals. TheThe variationvariation ofof d101m valuesvalues withwith texturaltextural anandd inclusionsinclusions inin botbothh pyropepyrope andand diamonds;diamonds; thethe latterlatter werewere structuralstructural changeschanges ofof thethe opal-CTopal-CT waswas measuredmeasured byby anan previouslypreviously identifiedidentified bbyy X-rayX-ray powderpowder diffractiondiffraction anandd XRDXRD powdepowderr method;method; withwith decreasingdecreasing dlOl'dm, highlyhighly servedserved asas a chromechrome diopsidediopside standard.standard. E.SE.5.. orderedordered cristobalitecristobalite domainsdomains developdevelop surroundingsurrounding ththee domainsdomains ofof disordereddisordered cristobalite.cristobalite. ThisThis considerableconsiderable DieDie dickendicken BrunnerBrunner ausaus StSt Egidien.Egidien. differencedifference inin degreedegree ofof orderorder ofof stackingstacking betweebetweenn thethe twotwo W.W. LEONHARDT.LEONHARDT. Mineralien Welt, 8(5),8(5), 1997,28-31,21997, 28-31, 2 maps.maps. typetypess ofof domaindomain impliesimplies changeschanges inin thethe growthgrowth processprocess ooff thethe crysta!.crystal. R.A.H.R.A.H. FineFine ornamentalornamental agatesagates areare describeddescribed fromfrom StSt Egidien,Egidien, Saxony,Saxony, Germany.Germany. DetailsDetails ofof thethe occurrenceoccurrence areare given.given. M.O'D.M.O'D. GemGem TradeTrade LabLab notesnotes..

T.T. MOSES,MOSES, I.I. REINITREINITZZ ANDAND S.F.S.F. MCCLURE.MCCLURE. Gems & Gemology, Dendritenachat:Dendritenachat: 'kristalline'kristalline Pflanzenwelt'.Pflanzenwelt'. 34(1),1998,44-9,1234(1), 1998, 44-9,12 illus.illus. inin colour.colour. W.W. LERGIER.LERGIER. Lapis, 22(11),22(11), 1997,1997,25-8 25-8,, illus.illus. inin colour.colour. ColombianColombian emeraldsemeralds withwith three-phasethree-phase inclusionsinclusions IllustrationsIllustrations andand discussiondiscussion ofof notablenotable examples,examples, werewere foundfound withwith a solidsolid inclusioninclusion ofof triangulartriangular shapeshape andand mostlymostly fromfrom MinaMinass Gerais,Gerais, BrazilBrazil,, ofof dendriticdendritic agate.agate. notnot cubic;cubic; thisthis isis possiblpossiblyy duedue ttoo spacespace restrictionsrestrictions duringduring M.O'D.M.O'D. formationformation.. TheThe triangulartriangular platinuplatinumm inclusionsinclusions seenseen iinn syntheticsynthetic emeraldsemeralds shouldshould notnot bbee confusedconfused withwith naturalnatural TeachingTeaching gemologygemology atat thethe undergraduateundergraduate inclusions.inclusions. A largelarge greenish-bluegreenish-blue fibrousfibrous roughrough andand a universityuniversity level.level. cabochoncabochon ofof thethe samesame colourcolour werewere foundfound toto bbee hemimorphite,hemimorphite, ththee firstfirst timetime thisthis materialmaterial hadhad beebeenn seenseen atat 332 A.A.A.A. LEVINSON.LEVINSON. Mineralogical Association of Canada thethe GIAGIA LabLab sincesince 1971.1971. A RamanRaman ImagingImaging MicroscopeMicroscope Newsletter, 57, 4-12, 1998. Newsletter, 57, 4-12,1998. SystemSystem waswas usedused toto identifyidentify somesome smallsmall crystalcrystal inclusions,inclusions, UniversityUniversity coursescourses inin gemmologygemmology heldheld atat ththee whichwhich reachedreached ththee surfacesurface ofof a greengreen cabochoncabochon jadeitejadeite,, aass undergraduateundergraduate levellevel areare thoughtthought toto benefibenefitt bothboth zircon.zircon. A cabochon-cutcabochon-cut yelloyelloww cat's-eyecat's-eye waswas founfoundd toto bebe gemmologygemmology studentsstudents andand geology/mineralogygeology/mineralogy studentsstudents opalopal withwith thethe chatoyancychatoyancy causedcaused bbyy finefine anandd coarsecoarse whowho areare ableable toto shareshare thethe classes.classes. CanadianCanadian experienceexperience iinn needles,needles, possiblypossibly pseudomorphouspseudomorphous afterafter goethite.goethite. TwTwoo moremore thanthan oneone institutioninstitution isis outlined.outlined. M.O'D.M.O'D. reddish-brownreddish-brown scapolitesscapolites fromfrom TanzaniaTanzania botbothh exhibitedexhibited chatoyancychatoyancy andand oneone alsoalso hadhad sixsix additionaladditional weakerweaker rays.rays. VergleichendeVergleichende UntersuchungenUntersuchungen anan RhodolithenRhodolithen A rarerare bluish-greenbluish-green ovaloval brilliant-cutbrilliant-cut topaztopaz waswas foundfound ttoo verschiedenerverschiedener Provenienz.Provenienz. bebe natural,natural, thethe stonestone hadhad markedmarked colourcolour zoningzoning anandd displayeddisplayed nono radioactivity.radioactivity. SphericalSpherical blubluee cloudsclouds TH.TH. LIND,LIND, U.U. HENNHENN ANDAND C.C. MILISENDA.MILISENDA. Gemmologie c.c. surroundingsurrounding darkdark blueblue crystalcrystal inclusionsinclusions werewere seenseen iinn (ZeitschriftIZeitschrift der Deutschen Gemmologischen Gesellschaft), sapphiressapphires thatthat havehave beebeenn heat-treatedheat-treated toto a temperaturetemperature 47(1),47(1), 1998,1998, 53-9,53-9, 4 photographsphotographs,, 2 graphs,graphs, 2 tables,tables, approachingapproaching thethe meltingmelting pointpoint ofof sapphires.sapphires. J.JJ.J.. biblbib!.. TheThe examinedexamined rhodolitesrhodolites camecame fromfrom Tanzania,Tanzania, OrissaOrissa (India),(India), SriSri Lanka,Lanka, Malawi,Malawi, BrazilBrazil andand MadagascarMadagascar anandd TheThe colorcolor ofof mineralsminerals.. couldcould bebe subdividedsubdivided intointo threethree typestypes onon thethe basisbasis ooff theirthen- N.V.N.V. I'uTIVTSEVAPUTIVTSEVA ANDAND E.V.E.V. PRYAKHINA.PRYAKHINA. World of Stones, 12,12, visiblevisible absorptionabsorption spectra.spectra. TypeType 1 waswas foundfound onlyonly seldom,seldom, 1997,1997,34-7 34-7,, illus.illus. inin colour.colour. withwith thethe exceptionexception ofof thethe finfindd inin SialiSiali inin Orissa;Orissa; mostmost rhodo­rhodo­ DrawingDrawing fromfrom exhibitsexhibits formingforming parpartt ofof anan exhibitionexhibition litelite belongedbelonged toto typetype 2 (landaban);(landaban); typtypee 3 camecame mainlymainly fromfrom heldheld atat thethe MineralogicalMineralogical MuseumMuseum ofof thethe MoscowMoscow StateState Tanzania.Tanzania. AllAll typestypes havehave typicaltypical mineralmineral inclusionsinclusions suchsuch asas GeologicalGeological ProspectingProspecting Academy,Academy, notesnotes onon mineralmineral zircon,zircon, apatiteapatite andand rutile.rutile. TheThe originorigin ofof thethe stonesstones couldcould notnot coloratiocolorationn areare summarizedsummarized withwith a numbernumber ofof examples,examples, bbee determineddetermined byby microscopicmicroscopic examination.examination. E.SE.5.. somesome ofof ornamentalornamental species.species. M.O'D.M.O'D.

TextureTexture andand structurestructure ofof opal-CTopal-CT andand opal-Copal-C iinn GrosserGrosser RauchquarzfundRauchquarzfund amam PizPiz Giuf,Giuf, BiindnerBiindner volcanicvolcanic rocks.rocks. Oberland.Oberland. T.T. MAGASEMAGASE ANDAND M.M. AKIZUKI.AKIZUKI. Canadian Mineralogist, 35(4),35(4), 1997,947-58.1997, 947-58. VV.. SIALM-BosSARD.SIALM-BOSSARD. Lapis, 23(1),23(1), 1998,1998,42-5 42-5,, illus.illus. inin colour.colour. ForFor opalopal inin volcanicvolcanic rocksrocks fromfrom thethe HosakaHosaka andand AkaseAkase ExceptionalExceptional crystalscrystals ofof smokysmoky quartzquartz havehave beenbeen opalopal minesmines inin Japan,Japan, texturestextures ofof opal-CTopal-CT areare opticallyoptically recoveredrecovered inin a cavitycavity atat aboutabout 28002800 m onon PizPiz GiufGiuf inin thethe

J./. Gemm., 1998, 26, 5, 330-333330-333 BiindnerBiindner OberlandOberland ofof easterneastern Switzerland.Switzerland. SpecimensSpecimens uupp toto 1.21.2 m havhavee beebeenn foundfound asas crystalcrystal groupsgroups andand somesome ooff HET KASTEEL thethe finesfinestt examplesexamples areare displayeddisplayed atat thethe MuseumMuseum 'L'Laa Truaisch',Truaisch', CH-7188CH-7188 Sedrun.Sedrun. M.O'D.M.O'D. RussianRussian syntheticsynthetic pinkpink quartz.quartz. V.S.V.S. BALITSKY,BALITSKY, LB.LB. MAKHINA,MAKHINA, v.1.V.I. I'RYGOV,PRYGOV, A.A.A.A. MAR'IN,MAR'IN, LaLa geologiegeologie desdes gisementsgisements dede saphirssaphirs.. A.G.A.G. EMEL'CHENKO,EMEL'CHENKO, E.E. FRITSCH,FRITSCH, S.F.S.F. MCCLURE,MCCLURE, LuLu TAIlING,TAIJING, D.D. DEGHIONNO,DEGHIONNO, J.1.J.I. KOIVULAKOIVULA ANANDD e.C. SIMONET.SIMONET. Revue de gemmologie, 132, 19971997,, 21-321-3.. J.E.J.E. SHIGLEY.SHIGLEY. Gems & Gemology, 34(1),34(1), 1998,1998, 34-43,34-43, A shortshort studystudy ofof sapphiresapphire occurrenceoccurrence submittedsubmitted foforr 1616 illus.illus. inin colour.colour. thethe DiplomaDiploma ofof thethe UniversitUniversitee dede Gemmologie,Gemmologie, Nantes,Nantes, TheThe firstfirst reportedreported productionproduction ofof transparenttransparent syntheticsynthetic France.France. Sedimentary,Sedimentary, volcanicvolcanic andand metamorphicmetamorphic typestypes ooff pinkpink quartzquartz waswas inin 19921992 manufacturedmanufactured byb yRussian Russia n depositdeposit areare considered.considered. M.O'D.M.O'D. laboratories,laboratories, andand thethe firstfirst materialmaterial waswas commerciallycommercially availableavailable iinn 1994.1994. ItIt isis currentlycurrently produceproducedd nearnear MoscowMoscow underunder ththee namename ofof 'Flaming'Flamingoo quartz'.quartz'. TheThe syntheticsynthetic ImperfectionsImperfections andand inhomogeneitiesinhomogeneities inin singlesingle materialmaterial isis growngrown inin a solutionsolution containingcontaining ammoniumammonium fluoride (NH F) and silica at temperatures between 220°C crystalcrystalss asas a basisbasis toto distinguishdistinguish naturalnatural fromfrom fluoride (NH4 F) and silica at temperatures between 220°C syntheticsynthetic gemstones.gemstones. andand 350°e.350°C. TheThe pinkpink colourcolour isis produceproducedd bbyy subsequentsubsequent irradiationirradiation andand heatingheating togethertogether withwith a concentrationconcentration ooff I.I. SUNAGAWA.SUNAGAWA. Gemmologie (Zeitschrift der DeutschenDeutschen phosporusphosporus inin thethe fluoridefluoride solution.solution. AlthoughAlthough naturalnatural Gemmologischen Gesellschaft!,Gesellschaft), 47(1),47(1), 1998,1998, 45-52,45-52, 3 massivemassive roserose quartzquartz isis relativelyrelatively common,common, naturalnatural trans­trans­ diagrams,diagrams, bibl.bibl. parentparent singlesingle crystalcrystal pinkpink quartzquartz isis veryvery uncommonuncommon andand onlyonly foundfound inin MadagascarMadagascar andand Brazil.Brazil. TheThe authors,authors, bothboth TheThe authorauthor discussesdiscusses physicalphysical imperfectionsimperfections anandd fromfrom RussiaRussia andand thethe GIA,GIA, examinedexamined syntheticsynthetic materialmaterial chemical inhomogeneities in single crystal gemstones. chemical inhomogeneities in single crystal gemstones. andand naturalnatural quartzquartz fromfrom Brazil.Brazil. AlthoughAlthough theythey foundfound TheyThey areare a recordrecord ofof growthgrowth andand post-growthpost-growth historyhistory ooff manymany similaritiessimilarities betweebetweenn thethe stones,stones, advancedadvanced testingtesting thethe stonestone andand showshow thethe differencesdifferences betweenbetween naturalnatural andand techniquestechniques helpedhelped toto distinguishdistinguish thethe naturalnatural quartzquartz fromfrom syntheticsynthetic stonesstones asas wellwell asas differencesdifferences inin origin.origin. ThusThus theythey thethe synthetic.synthetic. IInn syntheticsynthetic materialmaterial thethe colourcolour bandingbanding serveserve asas diagnosticdiagnostic features.features. MethodsMethods ofof applicationapplication ooff waswas foundfound toto bebe alwaysalways parallelparallel toto thethe basalbasal facesfaces anandd thesethese featuresfeatures areare brieflybriefly explained.explained. E.SE.S.. oftenoften uneven,uneven, whilewhile inin thethe naturalnatural stonesstones thethe bandingbanding waswas obliqueoblique toto thethe axisaxis withwith featheryfeathery edges,edges, whichwhich waswas nonott seenseen inin thethe syntheticsynthetic stones.stones. AllAll syntheticsynthetic materialmaterial lackedlacked 333 TessinerTessiner Rauchquarze:Rauchquarze: diedie grosstengrossten KristalleKristalle twinning.twinning. TheThe infraredinfrared absorptionabsorption spectrumspectrum ofof ththee -1 yomvom Cavagnoli-Gletscher.Cavagnoli-Gletscher. syntheticsynthetic quartzquartz containedcontained a diagnosticdiagnostic bandband atat 34203420 cm-'cm and weak bands at 3500 and 3650 cm-1. J.J. S.S. WEISS.WEISS. Lapis, 23(2),23(2), 1998,1998, 36-7,36-7, illus.illus. inin colour.colour. and weak bands at 3500 and 3650 cm-'. J.J.

VeryVery finefine largelarge crystalscrystals ofof smokysmoky quartzquartz areare reportedreported GeGemm news.news. fromfrom thethe CavagnoliCavagnoli glacier,glacier, Ticino,Ticino, Switzerland.Switzerland. ThThee largestlargest crystalcrystal foundfound measuresmeasures 6060 x 7575 cmcm inin thicknessthickness andand M.L.M.L. JOHNSONJOHNSON ANDAND J.1.J.I. KOIVULA.KOIVULA. Gems & Gemology, 34(1)34(1),, 1998,1998, 50-{)2,50-62, 2233 illus.illus. inin colour.colour. length,length, weighingweighing 114114 kg.kg. M.O'D.M.O'D. A newnew syntheticsynthetic amethystamethyst fromfrom ChinaChina hashas beenbeen growngrown onon dome-shapeddome-shaped seedseed crystals.crystals. TheyThey werewere allall deepdeep purplepurple CulturedCultured pearlspearls fromfrom Indonesia.Indonesia. andand showeshowedd naturalnatural quartzquartz faces,faces, butbut FTIRFTIR spectroscopyspectroscopy -1 P.e.P.C. ZWAAN.ZWAAN. Gemmologie (Zeitschri(Zeitschriftft der DeutschenDeutschen showedshowed a peapeakk atat 35435455 cm-'cm inin thethe infraredinfrared spectrum,spectrum, Gemmologischen Gesellschafl),Gesellschaft), 47(1),47(1), 1998,1998 , 31-8,31-8 , whicwhichh confirmedconfirmed thetheyy werewere synthetic.synthetic. GlassGlass cabochonscabochons andand beadsbeads toto imitateimitate agateagate areare nownow beingbeing made.made. A brownbrown 8photographs,8photographs, 2 maps,maps, 2 tablestables,, bibl.bibl. andand nearlynearly opaqueopaque facetedfaceted syntheticsynthetic moissanitemoissanite CulturedCultured pearlspearls fromfrom differentdifferent localitieslocalities inin Indonesia,Indonesia, originatedoriginated fromfrom a newnew sourcesource inin Russia,Russia, whichwhich iiss producedproduced byby Pinctada maxima, werewere examined.examined. DoboDobo producinproducingg materialmaterial usingusing a vapourvapour depositiondeposition technique.technique. pearlspearls comecome fromfrom thethe AruAru Islands;Islands; therethere is,is, however,however, nownow SyntheticSynthetic bi-colouredbi-coloured amethystamethyst andand citrine,citrine, whichwhich a pearlingpearling projectproject byby anan AustralianAustralian companycompany nearnear KupangKupang resemblesresembles ametrineametrine fromfrom BoliviaBolivia isis nownow beingbeing inin WesWestt Timor;Timor; thisthis isis supposedsupposed toto reachreach a maximummaximum manufacturedmanufactured inin Russia.Russia. J.JJ.J.. capacitycapacity byby ththee yearyear 20002000 ofof 200-400200^400 thousandthousand pearls.pearls. DoboDobo pearlspearls areare silverysilvery whitewhite andand havehave a nacrenacre thicknessthickness GemGem TradeTrade LabLab notesnotes.. ofof 1.01.0 toto 2.02.0 mm,mm, theythey areare rarelyrarely round,round, oftenoften egg-egg- oror pear­pear- T.T. MOSES,MOSES, I.I. REINITZREINITZ ANDAND S.F.S.F. MCCLURE.MCCLURE. Gems & Gemology, shaped.shaped. LambokLambok MabeMabe pearlspearls havehave a hemi-sphericalhemi-spherical 34(1),1998,44-9,1234(1), 1998,44-9,12 illus.illus. inin colour.colour. nucleus consisting of artificial resin; the nacre has a nucleus consisting of artificial resin; the nacre has a RepolishedRepolished heat-treatedheat-treated rubiesrubies havehave beebeenn seenseen thickness of 0.4-1.1 mm. Kuta pearls are blister pearls thickness of 0.4-1.1 mm. Kuta pearls are blister pearls recentlyrecently withwith surfacesurface pitpitss thatthat havehave beenbeen partiallypartially withwith a nucleusnucleus ofof artificialartificial resinresin plusplus a pluplugg ofof anan echinoid;echinoid; repolishedrepolished andand showedshowed semi-circularsemi-circular grooves.grooves. WhenWhen theythey areare round,round, button-shapedbutton-shaped andand resembleresemble imitationimitation viewedviewed underunder magnificationmagnification anan orangey-pinkorangey-pink cabochoncabochon pearlpearlss becausbecausee ofof theirtheir sheensheen.. ItIt isis notnot knownknown wherewhere thesethese waswas foundfound toto bebe anan assemblageassemblage ofof a plasticplastic toptop andand aann areare grown.grown. E.SE.s.. aragonitearagonite basebase.. J.JJ.J..

Abstracts BOOK REVIEWS

Recovery and refining of precious metals. Beautifully produced and illustrated guide to the [Third edition] 'new' [i.e., relocated] Deutsche Edelsteinmuseum at Idar- Oberstein. Much of the text and illustrative matter is close C. W. AMMEN, 1997. Chapman and Hall, New York, pp xi, to that used for a description of the museum published in 441, softcover. £37.00. ISBN 0 412 72060 4. Der Aufschluss fairly recently and an advertisement for the The first edition has become known as the 'Precious publishers of Aufschluss appears on the back cover. metal bible7 and anyone connected with the manufacture, However, an insert gives a plan of the new building and testing or evaluation of jewellery should read this text arrangement of its exhibits and this is dated 1996. which approximates to a metal testing manual with copious explanations of how the testing results are obtained. The After a history of the museum and of the gemstone book opens with a very useful section on general chemistry industry in the Idar-Oberstein area, the book goes on to before proceeding to the chemistry of the precious (and describe the nature and testing of gem specimens before other) metals. Recovery and refining methods are described covering the major species in chemical order, the at considerable length, and the whole text is presented customary arrangement for a cabinet of minerals. Both lucidly in such a way that the reader can assimilate a good major and uncommon species are introduced and a great deal of serious metallurgy and at the same time find out many are illustrated by top class colour photographs. how to regard the precious metals that may turn up needing Organic and man-made materials are reviewed before to be tested. Appendices give a list of the naturally-occurring accounts of gemstone fashioning, naming and use. There chemical elements with their atomic weights and numbers, is a very short bibliography, a table of synthetic materials a list of some of the metallic salts and their contents and one and growers with the date of their first appearance and a of the best glossaries I have seen for some time. table of recently discovered gem species and varieties. An index concludes the book. M.O'D. While intended for a wide readership, students beginning a course in metallurgy in particular will find 334 many uses for the book and the price is very reasonable Gem minerals of Victoria. for so comprehensive a coverage of the field. M.O'D. W. D. BIRCH AND D. A. HENRY, 1997. (Mineralogical Society of Victoria: Special Publication No. 4), Melbourne, Handbook of mineralogy. Vol III: halides, pp 121. A$29.95 (plus A$14.00 economy air post). hydroxides, oxides. ISBN 0 959 4573 3 X. Although the State of Victoria is not the richest in J.W. ANTHONY, R.A. BIDEAUX, K.W. BLADH AND M.C. NICHOLS, 1997. Mineral Data Publishing, Tucson, Australia for gemstones, nevertheless it contains a considerable range of collectable gems. The aim of this pp ix, 628 Hardcover. Price on application. well-illustrated book is not to be a locality guidebook ISBN 0 9622097 2 4. (though each of the more important localities for each Three down and two to go! I refer of course to the species is listed and discussed), but rather to provide progress of this magnificent series which gives single assistance with the identification of the gem minerals. page coverage to each validated mineral species and which has been exceptionally well-received by the After an introductory chapter outlining the discovery mineralogical community. The first volume covered of gem deposits, those such as diamonds, sapphires, elements, sulphides, sulphosalts and some less important zircons and olivine which are typically associated with classes and the second, in two volumes gave (at last!) an basic volcanic rocks are described. Small diamonds have up-to-date survey of the silicates. The remaining two been found in alluvial deposits, most being discovered by volumes are scheduled to cover arsenates, phosphates, accident during treatment of wash dirt for gold and tin uranates and vanadates (one volume) and borates, recovery; no commercial deposits have been found and carbonates, sulphates and small groups which have not the primary source of the diamonds remains unknown. been dealt with already. Sapphires are of widespread occurrence as waterworn crystals in present-day streams and older gravels; blue is Gemmologists will find the present volume the dominant ^olour, but purple, yellow and brown interesting for the information given on oxides alone. A varieties are found. Pale rubies also occur but are rarer complete set of the Handbook should last a long time even and smaller than sapphires. Rounded grains of reddish though new species are arriving at the rate of around one brown to near colourless zicon are also found in stream a week. M.O'D. gravels at numerous localities. The primary sources of the sapphires and zircons are thought to be basalts and Führer durch das Deutsche Edelsteinmuseum. volcani-sedimentary rocks. Olivines and anorthoclase H. BANK, 1996. The Museum, Idar-Oberstein, Germany, occur in xenoliths and megacrysts in lava flows of the pp 128, illustrated in colour, softcover. Price on Newer Volcanics in the W of the state; scoria cones have application. yielded olivine fashioned to give peridot < 8 mm in size.

J. Gemm., 1998, 26, 5,334-339 IInn ththee areaareass ooff granitigraniticc rockrockss anandd pegmatitespegmatites,, tourmalintourmalinee AA translatiotranslationn ooff StenenStenen somsom flyterflyter ochoch brinner,brinner, firsfirstt iiss commocommonn bubutt mainlmainlyy aass schorlschorl;; elbaitelbaitee iiss extremelextremelyy rarerare.. publishepublishedd iinn 19919955 bbyy NorstedNorstedss ForlaForlagg StockholmStockholm,, ththee boobookk TopaTopazz hahass beebeenn founfoundd inin situsitu iinn granitegranitess aatt onlonlyy aa fefeww iiss pleasinglpleasinglyy produceproducedd anandd iiss intendeintendedd aass aann uncomplicateuncomplicatedd localitieslocalities,, bubutt waterworwaterwornn colourlescolourlesss ttoo blubluee fragmentfragmentss araree guidguidee ttoo amberamber,, ititss compositioncomposition,, modmodee ooff occurenceoccurence,, lorloree widespreawidespreadd iinn alluviaalluviall depositsdeposits.. IInn VictoriaVictoria,, ththee garnegarnett anandd ususee witwithh particulaparticularr emphasiemphasiss oonn materiamateriall frofromm ththee speciespeciess almandinealmandine,, spessartinespessartine,, pyropepyrope,, grossulagrossularr anandd BaltiBalticc areaarea.. PhotographPhotographss iinn coloucolourr araree founfoundd iinn almosalmostt evereveryy andraditandraditee havhavee beebeenn foundfound,, mainlmainlyy iinn streastreamm gravelsgravels,, bubutt openinopeningg anandd mapmapss araree provideprovidedd foforr majomajorr amber-producinamber-producingg fefeww havhavee beebeenn larglargee oorr transparentransparentt enougenoughh ttoo facetfacet.. QuartQuartzz areasareas:: ththee mapmapss areare,, howeverhowever,, insufficientlinsufficientlyy detailedetailedd foforr iiss ththee mosmostt commocommonn gegemm mineralmineral,, witwithh ththee varietievarietiess rocrockk seriouseriouss useuse.. AA 35-ite35-itemm bibliographbibliographyy leadleadss ththee readereaderr ttoo crystalcrystal,, amethystamethyst,, smoksmokyy quartquartzz anandd citrincitrinee alalll recordedrecorded;; furthefurtherr sourcesourcess ooff informationinformation:: II wawass surprisesurprisedd bbyy ththee agateagate,, chalcedonychalcedony,, jaspejasperr anandd commocommonn opaopall alsalsoo occuroccur.. omissioomissionn ooff FraqueFraquett (1987(1987)) anandd bbyy ththee inclusioinclusionn ooff ththee poopoorr ThThee boobookk iiss extremelextremelyy welwelll illustratedillustrated,, botbothh bbyy boobookk bbyy HungeHungerr (1977(1977)) ttoo whicwhichh aann incorrecincorrectt publicatiopublicationn numerounumerouss sketcsketchh mapmapss showinshowingg mosmostt ooff ththee localitielocalitiess datdatee iiss ascribedascribed.. AAss aa stimulustimuluss ttoo readerreaderss witwithh aann interesinterestt iinn mentionementionedd iinn ththee textextt anandd bbyy aann abundancabundancee ooff excellenexcellentt amberamber,, witwithh googoodd illustrationillustrationss anandd aatt aa reasonablreasonablee pricpricee ththee coloucolourr photographphotographss ooff rougroughh anandd facetefacetedd stonestoness foforr eaceachh ooff boobookk iiss wortworthh buyingbuying.. M.O'DM.O'D.. ththee principaprincipall localitieslocalities.. IItt endendss witwithh aa lislistt ooff somsomee 181800 referencesreferences,, aa localitielocalitiess indeindexx anandd aa glossaryglossary,, togethetogetherr witwithh GemstoneGemstoness ooff BrazilBrazil:: geologgeologyy anandd occurrencesoccurrences.. tabulatetabulatedd mineraminerall datdataa foforr VictoriaVictoriann occurrencesoccurrences,, anandd P.J.P.J.Y.V DELANEYDELANEY,, 19961996.. RevistRevistaa EscolEscolaa ddee MinasMinas,, OurOuroo PretoPreto.. clearlclearlyy fulfilfulfilss ththee author'author'ss intentionintentionss ooff providinprovidingg aa boobookk ttoo pppp 125125,, illustrateillustratedd iinn colourcolour,, softcoversoftcover.. US$5.00US$5.00.. assisassistt witwithh ththee identificatioidentificationn ooff manmanyy ooff ththee gegemm mineralmineralss ISBISBNN 8855 8611861122 0022 XX.. througthroughh ththee ususee ooff coloucolourr photographsphotographs.. R.A.HR.A.H.. ThThee apparentlapparentlyy impossiblimpossiblee doedoess happehappenn sometimessometimes!! A geologicageologicall survesurveyy ooff ththee majomajorr gem-fieldgem-fieldss ooff BrazilBrazil,, witwithh GemmGemmee dedell VicentinoVicentino.. notenotess foforr thosthosee wishinwishingg ttoo visivisitt somsomee ooff ththee locationslocations,, aann MM.. BOSCARDIBOSCARDINN ANANDD OO.. VV.. TESCARITESCARI,, 19961996.. MontecchiMontecchioo excellenexcellentt bibliographybibliography,, mapmapss ooff ththee depositdepositss anandd alalll aatt aa MaggioreMaggiore,, VicenzaVicenza,, ItalItalyy (Muse(Museoo CivicCivicoo 'G'G.. Zannato')Zannato').. ververyy modesmodestt priceprice.. ThiThiss iiss ononee ooff ththee mosmostt usefuusefull bookbookss II pppp 114114.. havhavee seeseenn foforr aa lonlongg timtimee anandd iitt iiss particularlparticularlyy welcomwelcomee DescriptionDescriptionss (ofte(oftenn \ accompanieaccompaniedd bbyy coloucolourr foforr ititss geologicageologicall basisbasis.. photographsphotographs)) araree givegivenn ooff gegemm materialmaterialss whicwhichh occuoccurr iinn ThThee textextt openopenss witwithh aa shorshortt historyhistory,, followefollowedd bbyy aa ththee VicenzVicenzaa areareaa ooff N NEE ItalyItaly.. ThesThesee rangrangee frofromm alabastealabasterr ttoo descriptiondescription,, ooff ththee diamondiamondd depositdepositss ooff BrazilBrazil.. EleveElevenn amberamber,, aragonite/calcitearagonite/calcite,, berylberyl,, brucitebrucite,, celestinecelestine,, feldfeld­­ majomajorr depositdepositss araree showshownn oonn aa sketch-masketch-mapp anandd alalll araree sparsspars,, garnetgarnet,, hematitehematite,, ilmeniteilmenite,, obsidianobsidian,, rhodochrositerhodochrosite,, describeddescribed.. ShorShortt notenotess oonn modemodess ooff occurrencoccurrencee araree givengiven:: 335 rhodoniterhodonite,, serpentineserpentine,, silicsilicaa mineralmineralss (agate(agate,, amethystamethyst,, thesthesee includincludee presently-helpresently-heldd theorietheoriess oonn hohoww ththee depositdepositss carneliancarnelian,, chalcedonychalcedony,, jasperjasper,, quartzquartz,, rosrosee quartzquartz)) anandd formedformed.. NoteNotess oonn present-dapresent-dayy statustatuss anandd workingworkingss araree zeolitezeolitess (analcite(analcite,, mordenitmordenitee anandd natrolite)natrolite).. JohannsenitJohannsenitee provideprovidedd wherwheree appropriateappropriate.. ThThee beryberyll mineralmineralss araree occuroccurss witwithh rhodonitrhodonitee aatt MtMtee CivillinaCivillina,, anandd hahass beebeenn treatetreatedd iinn ththee samsamee wayway,, witwithh notenotess oonn earlearlyy discoveriediscoveriess fashionefashionedd intintoo cabochonscabochons.. OlivinOlivinee (peridot(peridot)) iiss welwelll anandd oonn ththee currently-workecurrently-workedd depositdepositss aatt CarnaibCarnaibaa anandd representerepresentedd iinn ththee areareaa arounaroundd SalcedSalcedoo anandd cucutt stonestoness ooff SocotSocotoo (Bahia)(Bahia),, ItabirItabiraa anandd CapoeiranCapoeiranaa (Mina(Minass Gerais)Gerais),, 0.36-3.60.36-3.688 cctt araree reportedreported.. XonotlitXonotlitee iiss founfoundd aatt ththee contaccontactt SantSantaa TerezinhTerezinhaa ddee GoiasGoias,, PirenopoliPiren6poliss anandd PorangatPorangatuu betweebetweenn aa monzonitmonzonitee anandd dolomitidolomiticc limestonlimestonee neanearr (Goias)(Goiiis),, TauaTaua,, (Ceara)(Ceara).. AquamarinAquamarinee depositdepositss araree describedescribedd MolinMolinii ddii LaghLaghii anandd yieldyieldss translucentranslucentt cucutt stonestoness undeunderr southeastersoutheasternn pegmatitpegmatitee provincprovincee anandd northeasternortheasternn (includin(includingg aa 12.112.199 cctt ovaovall showinshowingg ththee characteristicharacteristicc pegmatitpegmatitee provincprovincee anandd thertheree araree briebrieff notenotess oonn otheotherr pinkispinkishh whitwhitee appearancappearancee ooff thithiss mineral)mineral).. GemmGemmyy BraziliaBraziliann beryberyll depositsdeposits.. ChrysoberylChrysoberyl,, topaztopaz,, tourmalinetourmaline,, goldegoldenn browbrownn zirconzirconss occuoccurr iinn streastreamm gravelgravelss anandd havhavee opaopall anandd quartquartzz araree dealdealtt witwithh iinn similasimilarr fashiofashionn whilwhilee yieldeyieldedd cucutt stonestoness uupp ttoo 4.14.111 ctct.. R.A.HR.A.H.. brazilianitebrazilianite,, amazoniteamazonite,, andalusiteandalusite,, kunzitkunzitee anandd garnegarnett araree describedescribedd iinn aa sectiosectionn oonn otheotherr gemstonesgemstones.. CalcitCalcit:: dadass ffonnenreichste ormenreichste MineraMinerall dederr ErdeErde.. BriefeBrieferr detaildetailss oonn otheotherr speciespeciess araree givegivenn iinn ththee firsfirstt ooff 19981998.. ChristiaChristiann WeisWeisee VerlagVerlag,, MunchenMiinchen.. pppp 9696,, illustrateillustratedd threthreee appendicesappendices:: speciespeciess namename,, locatiolocationn anandd statstatee araree ththee iinn colourcolour,, softcoversoftcover.. ISBISBNN 33 921659216566 4444 33.. onlonlyy factsfacts providedprovided:: rubrubyy anandd sapphirsapphiree cacann bbee founfoundd iinn thithiss WitWithh ththee greatesgreatestt numbenumberr ooff recorderecordedd formsforms,, calcitcalcitee iiss listlist,, togethetogetherr wiwihh peridotperidot,, greegreenn spodumenespodumene,, spinelspinel,, zircozirconn aa worthworthyy subjecsubjectt foforr ththee lateslatestt numbenumberr ooff ththee beautifully­beautifully- anandd othersothers.. ThThee seconsecondd appendiappendixx givegivess suggestionsuggestionss oonn hohoww produceproducedd anandd informativinformativee extraLapisextraLapis seriesseries.. WhilWhilee ttoo organizorganizee fielfieldd triptripss ttoo BraziliaBraziliann gegemm depositdepositss anandd ththee 1010-- gemmologistgemmologistss wilwilll particularlparticularlyy welcomwelcomee ththee expositioexpositionn ooff pagpagee bibliographbibliographyy followfollowss aa glossarglossaryy iinn ththee thirthirdd appendixap'pendix.. ththee ususee ooff calcitcalcitee iinn obtaininobtainingg interferencinterferencee figurefiguress anandd ooff ThThee boobookk iiss lucidllucidlyy writtewrittenn anandd aa pleasurpleasuree ttoo readread.. II ititss varievariedd fluorescenfluorescentt effectseffects,, mineralogistmineralogistss anandd collectorcollectorss shoulshouldd welcomwelcomee similasimilarr treatmentreatmentt foforr otheotherr majomajorr wilwilll finfindd equaequall pleasurpleasuree iinn ththee detaildetailss ooff classiclassicc gem-producingem-producingg countriescountries.. M.O'DM.O'D.. occurrencesoccurrences.. M.O'DM.O'D.. FrankliFranklinn anandd SterlinSterlingg HillHill,, NeNeww JerseyJersey:: ththee ThThee AmbeAmberr bookbook.. world'world'ss mosmostt magnificenmagnificentt mineraminerall depositsdeposits.. AA.. DAHLSTRODAHLSTROMM ANANDD L.L . BROST,BROST , 1996.1996 . GeoscienceGeoscience Press,Press , P.JP.J.. DUNNDUNN,, 19951995.. Franklin-OgdensburFranklin-Ogdensburgg MineralogicaMineralogicall TucsoTucsonn AZAZ.. pppp 134134,, illustrateillustratedd iinn colourcolour,, hardcoverhardcover.. SocietySociety,, FrankliFranklinn NJNJ.. pppp 978978,, illustrateillustratedd iinn US$27.00US$27.00.. ISBISBNN 00 945009450055 2233 77.. black-and-whiteblack-and-white,, papepaperr covercover.. £150.00£150.00..

BookBook Reviews SinceSince ththee areaarea ofof FranklinFranklin,, NeNeww Jersey,Jersey, hashas attractedattracted soso ooff ifif nonott alalll ooff thethe otherother theoriestheories oonn ththee basibasicc formatioformationn ooff manmanyy mineralmineral collectorcollectorss whwhoo alsoalso havehave aann interesinterestt iinn gemgem opaopall mustmust taktakee placplacee becausbecausee ofof experimentexperimentss carriecarriedd outout speciesspecies,, thisthis highlhighlyy individuaindividuall presentatiopresentationn deservesdeserves asas bbyy a manman frofromm LightningLightning RidgeRidge,, NeNeww SoutSouthh WalesWales,, whowho muchmuch publicitpublicityy outsideoutside thethe UniteUnitedd StatesStates aass iitt cancan get.get. hahass succeededsucceeded iinn growinggrowing opalopalss from'from 'opa opall dirtdirt'' iinn a liquidliquid FirsFirstt ofof allall,, thethe absencabsencee ooff anyany coloucolourr iiss nonott a disadvantagedisadvantage inin glasglasss jarjarss inin aann incrediblincrediblyy shorshortt timetime ((aa fewfew daysdays ttoo sixsix sincesince thethe black-and-whitblack-and-whitee reproductionsreproductions araree ooff excellentexcellent monthsmonths,, followedfollowed bbyy ththee secretsecret electrolyteelectrolyte beinbeingg siphonedsiphoned qualitqualityy (and(and iinn anyany casecase ththee costcost ooff colourcolour useusedd onon soso largelarge ofofff throughthrough a smalsmalll holholee inin thethe container'container'ss covercover,, allowingallowing a scalescale wouldwould havehave beenbeen prohibitive).prohibitive). Secondly;Secondly, openingopening aiairr contactcontact ttoo drdryy ththee stone).stone). TheseThese opalopalss araree saidsaid toto bebe ththee firstfirst sectiosectionn ttoo finfindd a bibliographbibliographyy headingheading ththee texttext indistinguishablindistinguishablee bbyy sightsight frofromm naturanaturall opalopal,, bubutt havhavee notnot wouldwould perhapperhapss surprissurprisee andand disconcertdisconcert somesome readers:readers: yeyett beebeenn scientificallyscientifically analysed;analysed; a lolott ofof worworkk hahass beenbeen I feltfelt thatthat thisthis waswas thethe placeplace toto putput itit andand sincesince itit coverscovers donedone,, bubutt ththee experimenteexperimenterr quitquitee reasonablreasonablyy wantwantss toto 6633 pagepagess (approximately(approximately 30030000 entriesentries)) ththee scalescale ofof thethe publispublishh ththee resultresultss himself.himself. WeWe araree thuthuss lefleftt witwithh variousvarious wholwholee undertakinundertakingg isis apparentapparent atat once.once. statements,statements, bubutt a lolott ofof thethe author'author'ss worworkk remindremindss ononee ooff a current British advertising campaign on the lines of'... I ThiThiss areaarea doedoess meritmerit a surveysurvey ooff thisthis sizsizee andand quality:quality: a current British advertising campaign on the lines of ' ... I don't know the answer but I know a man who does'. mininminingg operationoperationss carriecarriedd ououtt bbyy ththee NeNeww JerseJerseyy ZincZinc don't know the answer but I know a man who does'. Nevertheless, the evidence of fossil pseudomorphs leads CompanyCompany andand manmanyy otherother bodiebodiess areare fullfullyy describeddescribed andand Nevertheless, the evidence of fossil pseudomorphs leads one to the conclusion that opalization does not a mostmost usefuluseful chronologychronology cancan bebe foundfound atat thethe endend ofof thethe one to the conclusion that opalization does not neccessarily require a geological time-scale in which to firstfirst partpart.. CollectorsCollectors anandd manmanyy gemmologistgemmologistss wilwilll knowknow neccessarily require a geological time-scale in which to operate. thathatt thethe areareaa hahass produceproducedd somethingsomething likelike 1010 peperr centcent ooff operate. alalll validatevalidatedd mineraminerall speciespeciess andand thatthat 6699 ofof themthem werewere firstfirst PuttingPutting asideaside thesthesee reservations,reservations, thithiss boobookk doesdoes describedescribedd frofromm thisthis localitlocalityy (this(this isis a record)record).. SomethingSomething succeedsucceed iinn givingivingg anan overaloveralll accountaccount ofof ththee occurrencoccurrencee ooff liklikee 1010 peperr centcent ofof ththee speciesspecies araree foundfound nowherenowhere else.else. opals,opals, nonott onlyonly iinn AustraliaAustralia,, thethe UniteUnitedd StatesStates anandd Mexico,Mexico, WhileWhile somsomee specimensspecimens cacann bbee fashionefashionedd iinn ononee wawayy oror bubutt alsalsoo iinn BritisBritishh Columbia,Columbia, Honduras,Honduras, Austria,Austria, thethe anotheranother,, bbyy farfar ththee mosmostt presentablpresentablee oneoness fluorescfluorescee anandd itit CzecCzechh RepublicRepublic,, SlovakiaSlovakia anandd HungaryHungary.. ThThee descriptionsdescriptions iiss thithiss propertpropertyy whicwhichh placeplacess FrankliFranklinn ververyy highhigh oonn ththee listlist ofof opaopall depositdepositss inin OpaOpall ButteButte,, OregonOregon,, andand ththee VirginVirgin ofof sitesitess frofromm whichwhich ornamentaornamentall mineralmineralss cancan bbee recovered.recovered. ValleValleyy areaarea ooff HumboldHumboldtt CountyCounty,, NevadaNevada,, areare describeddescribed EverythingEverything isis herehere anandd ththee wholewhole workwork iiss a modelmodel inin detail,detail, andand inin thethe sectiosectionn onon noteworthnoteworthyy opalopalss detailsdetails whicwhichh I hophopee willwill bbee followefollowedd bbyy othersothers:: thisthis author'sauthor's areare givegivenn ofof ththee RoeblinRoeblingg opalopal (2560(2560 ctct)) anandd ththee BonanzaBonanza dedicationdedication isis universalluniversallyy knowknownn anandd admiredadmired andand wewe opalopal (2(255 585866 ctct)) bothboth fromfrom VirginVirgin Valley.Valley. OpalOpal beinbeingg whatwhat musmustt hopehope forfor echoeechoess frofromm otheotherr writerwriterss aboutabout otherother itit isis,, manmanyy ofof ththee black-and-whiteblack-and-white photographphotographss iinn thethe texttext 336 majomajorr sitessites,, includingincluding somesome gemstone-producinggemstone-producing ones.ones. areare uninspiringuninspiring,, bubutt 2222 colourcolour plateplatess demonstratdemonstratee thethe M.O'D.M.O'D. amazinamazingg variabilityvariability inin plaplayy ofof colourcolour toto bbee seeseenn inin opalsopals eveevenn fromfrom ththee samesame minemine.. A boobookk thathatt managesmanages toto bbee bothboth provokingprovoking anandd informativeinformative,, whilewhile wwee awaitawait ththee promisedpromised ThThee worldworld ooff opalsopals.. definitivdefinitivee worworkk onon thethe geologygeology anandd chemistrchemistryy ofof opaopall byby A.A. W.W. ECKERTECKERT,, 1997.1997. JohJohnn WileyWiley & Sons,Sons, Inc.,Inc., NeNeww YorkYork andand ththee 'man'man whwhoo does'.does'. R.A.H.R.A.H. Chichester.Chichester, pppp xivxiv,, 448448.. £60.00£60.00.. ISBISBNN 0 4711339471 133973.7 3. ThiThiss isis thethe firstfirst comprehensivcomprehensivee boobookk oonn opalsopals foforr overover Jean-PierrJean-Pierree BertranBertrandd dede LorLornn (1799-1878)(1799-1878),, thirtthirtyy yearyearss anandd claimsclaims ttoo givgivee a completecomplete guidguidee ttoo thethe prospecteur-mineralogistprospecteur-mineralogistee vellave,vellave, etet sonson oeuvreoeuvre sciencescience anandd historhistoryy ooff thithiss gegemm materialmaterial.. AfteAfterr a definitiondefinition gemmologiquegemmologique.. ooff exactlexactlyy whawhatt constituteconstitutess anan opal,opal, thethe authorauthor provideprovidess a neneww looklook aatt opaopall formation,formation, anandd thisthis isis followedfollowed byby F.F. HH.. FORESTIERFORESTIER,, 1995.1995. CahiersCahiers dduu Haute-Loire.Haute-Loire. pppp6 666 chapterchapterss describindescribingg opalizeopalizedd fossilfossilss andand pseudomorphs,pseudomorphs, illustrateillustratedd iinn black-and-whiteblack-and-white,, softcoversoftcover.. FF80.00FF80.00.. ththee mythologmythologyy ofof opalsopals (th(thee 'ba'badd luckluck'' populapopularr imageimage Jean-PierreJean-Pierre BertranBertrandd ddee LorLomn (1799-1878(1799-1878)) waswas beinbeingg blameblamedd onon ththee oneone ooff SirSir WalterWalter Scott'sScott's Waverly occupiedoccupied withwith geologicageologicall anandd mineralogicamineralogicall studiestudiess forfor Novels 'Anne of Geierstein'),Geierstein'), famousfamous anandd otherwiseotherwise mostmost ooff hihiss lifelife,, asas a chilchildd obtaininobtainingg specimensspecimens ooff noteworthynoteworthy opalsopals,, typestypes ooff opals,opals, thethe World'World'ss majormajor opalopal sapphiresapphiress anandd zirconszircons occurringoccurring iinn ththee vicinitvicinityy ooff Espaly,Espaly, occurrences,occurrences, andand a glossarglossaryy ofof opal-relateopal-relatedd terms;terms; thertheree isis thethe towtownn ofof hihiss birthbirth.. ThisThis smalsmalll boobookk shedssheds lightlight onon thethe alsoalso aann extensivextensivee bibliographbibliographyy andand aann index.index. activitiesactivities ofof a pioneepioneerr FrenchFrench mineralogistmineralogist witwithh anan interestinterest TheThe chapterchapter onon ththee modemode ooff formatioformationn ofof opalsopals isis inin ornamentaornamentall minerals.minerals. ByBy 18401840 BertranBertrandd ddee LorLomn (the(the basebasedd largellargelyy oonn thethe thesisthesis thatthat mostmost ooff whawhatt hashas beenbeen seconsecondd elementelement ooff ththee surnamsurnamee arrivingarriving throughthrough taughttaught abouaboutt opalopalss hahass beebeenn basebasedd oonn theorietheoriess nownow marriagemarriage)) waswas contributingcontributing ttoo mineralogicalmineralogical reports,reports, provenproven,, inin parpartt aatt leastleast,, ttoo bbee incorrectincorrect.. ThThee author'author'ss stylestyle includinincludingg itemitemss oonn garnetsgarnets andand corundumcorundum fromfrom isis distinctlydistinctly idiosyncraticidiosyncratic,, andand iitt isis difficuldifficultt ttoo unraveunravell thethe Haute-LoirHaute-Loiree andand oonn bothboth jadjadee minerals.minerals. ThThee areareaa ooff ususee ooff suchsuch termtermss aass atomatom migratiomigrationn [metasomatism?][metasomatism?] andand Riou-PezouillouRiou-Pezouillou,, iinn Haute-Loire,Haute-Loire, wawass extensivelyextensively thethe definitiondefinition ofof aann electrolyteelectrolyte aass ''aa liquiliquidd carryincarryingg a describeddescribed,, witwithh ititss gemgem mineralsminerals,, inin a papepaperr publishepublishedd inin chemicachemicall thathatt generatesgenerates anan electricalelectrical pathwapathwayy throughthrough 1844,1844, subsequensubsequentt yearyearss uupp ttoo 18781878 producinproducingg moremore studiesstudies anything'anything'.. TheThe worworkk ofof SandersSanders andand DarragDarraghh inin 19651965 ofof thithiss anandd otheotherr areasareas.. TheThe boobookk isis a veryvery usinusingg electronelectron microscopmicroscopyy ttoo demonstratedemonstrate thatthat preciousprecious well-constructedwell-constructed studystudy ooff thethe wayway iinn whichwhich differentdifferent opaopall consistsconsists ofof alignealignedd lepisphereslepispheres andand voidvoidss givinggiving riserise handshands contributedcontributed ttoo FrencFrenchh determinativdeterminativee generagenerall andand ttoo a three-dimensionathree-dimensionall diffractiodiffractionn gratinggrating isis gemmologicagemmologicall mineralogymineralogy througthroughh mosmostt ooff thethe lastlast acknowledgedacknowledged,, bubutt wwee areare toltoldd thatthat ththee refutatiorefutationn ooff partpart centurycentury:: thertheree areare manymany usefuluseful footnotesfootnotes andand referencesreferences

/J.. Gemm., 1998, 26, 5, 334-339334-339 whilewhile allall BertrandBertrand dede Lom'sLom's paperspapers areare fullyfully abstracted.abstracted. arrangementarrangement ofof physicalphysical andand opticaloptical propertpropertyy datadata iiss alsoalso ThereThere areare alsoalso notesnotes onon thethe dispositiondisposition ofof hishis propertyproperty explained,explained , followedfollowed bbyy notenotess onon phasphasee relationshipsrelationships andand afterafter hishis death.death. M.O'D.M.O'D. occurrences.occurrences. FinallyFinally thethe structurestructure usedused forfor localitylocality citationcitation isis explained:explained: thethe exclamationexclamation markmark (!)(!) isis usedused ttoo indicateindicate Dana'sDana's newnew mineralogy:mineralogy: thethe systemsystem ofof mineralogymineralogy specimensspecimens ofof exceptionalexceptional museummuseum qualityquality - thithiss remindsreminds ofof J.D.J.D. DanaDana anandd E.S.E.S. Dana.Dana. [8th[8th edition,edition, entirelyentirely meme ofof thethe nineteentnineteenthh andand earlyearly twentieth-centurtwentieth-centuryy BritishBritish countycounty floras,floras, whenwhen thethe samesame symbolsymbol indicatedindicated thathatt thethe rewrittenrewritten andand greatlygreatly enlarged]enlarged] authorauthor hadhad foundfound ththee specimenspecimen described!described! R.V. GAINES,GAINES, H.H. C.C. W.W. SKINNER,SKINNER, E.E. E.E. FOORDFOORD,, B.B. MASONMASON ANDAND HavingHaving reareadd thethe prefatoryprefatory mattematterr ththee readereaderr isis alreadyalready A.A. ROSENZWEIG,ROSENZWEIG, 1997.1997. JohnJohn WileyWiley & SonsSons Inc.,Inc., expectingexpecting a highlyhighly compressedcompressed texttext andand thithiss isis whatwhat isis NewNew York.York, ppxlvpp xlv,, 1819,1819, hardcover.hardcover. £191.00.£191.00. presented.presented. I foundfound it,it, togethetogetherr witwithh anan excellently-chosenexcellently-chosen ISBNISBN 0 4711931047119310 O.0. typefacetypeface andand good-qualitygood-quality [acid-free][acid-free] paperpaper,, particularlyparticularly ForFor mineralogistsmineralogists thisthis hashas toto bebe thethe mostmost importantimportant pleasingpleasing toto read.read. I notenotedd oneone oror twotwo smallsmall misprintmisprintss andand newnew publicationpublication ofof thethe lastlast fewfew years.years. EvenEven a continuationcontinuation nono doubtdoubt therethere areare othersothers butbut severalseveral samplessamples chosenchosen toto ofof DanaDana 7th7th editionedition [D7][D7] hadhad rapidlyrapidly beenbeen lostlost toto sightsight andand identifyidentify smallsmall errorserrors werweree amazinglyamazingly freefree fromfrom themthem thethe lastlast completecomplete editionedition ofof thethe System waswas publishepublishedd latelate (there(there seemsseems ttoo bebe slightslight confusionconfusion betweebetweenn occurrenceoccurrence ooff inin thethe lastlast century.century. ForFor thosethose newnew ttoo taxonomictaxonomic ththee YogoYogo andand MissouriMissouri RiverRiver sapphiresapphire depositsdeposits - thithiss isis mineralogy,mineralogy, thethe System, firstfirst privatelyprivately publishedpublished inin 1837,1837, perhapperhapss unduunduee compressioncompression ofof ththee text)text) - bubutt thethe boobookk isis waswas ththee firstfirst large-scallarge-scalee attemptattempt inin EnglisEnglishh toto classifyclassify intendedintended onlyonly ttoo leadlead ttoo mormoree detaileddetailed descriptionsdescriptions mineralmineral speciesspecies usinusingg datadata provideprovidedd fromfrom earlierearlier workersworkers elsewhereelsewhere andand smallsmall omissionsomissions andand errorserrors areare tootoo triviatriviall toto andand leavingleaving behindbehind medicalmedical andand magicalmagical propertiesproperties asas a mentionmention.. SpeciesSpecies describeddescribed uupp toto ththee endend ofof 19951995 areare basibasiss forfor systematization.systematization. TheThe secondsecond editionedition followefollowedd inin includedincluded - atat thethe timetime ththee reviewreview waswas writtewrittenn thertheree werewere 18441844 andand thethe thirdthird inin 1850.1850. Today'sToday's readerreader ofof thesethese (very(very approximatelyapproximately 3,7003,700 validatevalidatedd species.species. rare)rare) earlyearly editionseditions (and(and gemmologygemmology students)students) woulwouldd findfind ThisThis isis a magnificenmagnificentt effort:effort: ththee pricpricee isis highhigh bubutt itit isis thethe BerzelianBerzelian (chemical)(chemical) notationnotation usedused harhardd toto understandunderstand worthworth everyevery centcent ofof it.it. M.O'D.M.O'D. andand today'stoday's formulaeformulae areare muchmuch simplersimpler inin thisthis respectrespect asas strangestrange symbolssymbols havehave beebeenn banished!banished! FollowingFollowing ththee sixthsixth editionedition seriousserious attemptsattempts werewere GeologicalGeological SurveySurvey andand MinesMines BureauBureau ooff beingbeing madmadee toto establishestablish a seventhseventh asas farfar backback asas 19151915 butbut SriSri LankaLanka.. nono volumevolume appearedappeared untiuntill 19441944 whenwhen ththee firstfirst volumvolumee waswas Colombo,Colombo, 19971997 publishedpublished.. A secondsecond volumevolume andand a thirdthird (on(on silicasilica alone)alone) TheThe sevenseven sheetssheets underunder reviewreview areare8101113141 810 111314 166 andand followedfollowed bubutt bbyy thenthen itit waswas 19601960 andand thethe numbernumber ofof newnew 337 1717 andand whilewhile 16,16, coveringcovering thethe Colombo-RatnapuraColombo-Ratnapura area,area, species, established by many new laboratory techniques species, established by many new laboratory techniques willwill bebe ofof thethe highesthighest interest,interest, gemstonesgemstones featurefeature onon somesome was outstripping the production capacity of editors and was outstripping the production capacity of editors and ofof thethe otherother sheets.sheets. EachEach sheetsheet carriescarries identicalidentical notesnotes onon publishers. publishers. thethe geologygeology ofof SriSri LankaLanka asas a wholewhole andand thenthen givesgives a ThusThus ththee conceptconcept ofof a single-volumesingle-volume eightheighth edition,edition, usefuluseful summarysummary ofof thethe locallocal conditionsconditions andand thethe economiceconomic thisthis timetime withwith fivfivee co-authorsco-authors wawass a boldbold oneone butbut itit hashas mineralsminerals found.found. SheetSheet 8 (Anuradhapura-Polonnaruwa)(Anuradhapura-Polonnaruwa) succeededsucceeded brilliantly:brilliantly: eveneven thoughthough manmanyy crystalcrystal includesincludes majormajor apatiteapatite deposits:deposits: sheetsheet 1010 coverscovers thethe coastalcoastal drawings,drawings, referencesreferences andand localitylocality informationinformation havehave notnot regionregion ofof BattuluBattulu Oya-Kurunegala:Oya-Kurunegala: sheetsheet 1111 foundfound a placplacee thisthis time,time, suchsuch datadata cancan easilyeasily bbee obtainedobtained (Dambulla-Pallegama)(Dambulla-Pallegama) includesincludes thethe majormajor ElaheraElahera gemgem fromfrom journaljournalss andand thusthus viviaa thethe Internet.Internet. TheThe authorsauthors teltelll usus field:field: sheetsheet 1313 coverscovers Kochchikade-Attanagalla:Kochchikade-Attanagalla: sheetsheet 1414 thatthat eveneven duringduring thethe yearsyears ofof compilationcompilation ththee numbenumberr ooff (Kandy-Hanguranketa)(Kandy-Hanguranketa) includesincludes gemgem depositsdeposits hostinghosting speciesspecies ttoo bebe coveredcovered nearlnearlyy doubled.doubled. spinel,spinel, sapphirinesapphirine andand ornamentalornamental feldsparfeldspar mineralsminerals PrefatoryPrefatory materialmaterial isis shortshort thougthoughh therethere isis a usefuluseful amongamong others:others: sheetsheet 1717 (Nuwara(Nuwara Eliya-Haputale)Eliya-Haputale) alsoalso indexindex ofof thethe symbolssymbols usedused forfor thethe maimainn bibliographicbibliographic includesincludes majormajor gemgem depositsdeposits (Ratnapura,(Ratnapura, PelmadullaPelmadulla andand sources.sources. TheThe maimainn textextt isis arrangedarranged inin chemicalchemical orderorder (and(and BalangodaBalangoda inin particular)particular).. ItIt isis veryvery rarerare forfor mapmapss ttoo bebe includeincludess a numbenumberr ofof anthropogenicanthropogenic andand syntheticsynthetic availableavailable fromfrom gem-producinggem-producing countriescountries andand minerals).minerals). A hierarchicalhierarchical numberingnumbering systemsystem (updating(updating thesethese beautifully-producedbeautifully-produced examplesexamples areare greatlygreatly thatthat usedused inin thethe incompletincompletee seventhseventh edition)edition) isis usefuluseful andand welcomed.welcomed. M.o'D.M.O'D. thethe profusprofusee andand complexcomplex silicatsilicatee speciesspecies areare herheree classifiedclassified accordingaccording ttoo a structural-chemicalstructural-chemical systemsystem developeddeveloped byby Dana'sDana's mineralsminerals andand howhow toto studystudy themthem (after(after twtwoo ofof ththee co-authors.co-authors. Name,Name, chemicalchemical formula,formula, isostruc­isostruc- EdwardEdward SalisburySalisbury Dana).Dana). [Fourth[Fourth edition]edition] turaturall substitutions,substitutions, vacancievacanciess oror voidsvoids inin structures,structures, namename derivations,derivations, groups,groups, dimorphsdimorphs andand polymorphs,polymorphs, c.C. S.S. HURLBUTHURLBUT ANDAND W.W. E.E. SHARPSHARP JR,JR , 1998.1998. JohnJohn WileyWiley & synonyms,synonyms, varietievarietiess andand polytypepolytypes s areare allall indicated.indicated. TheThe Sons,Sons, Inc.,Inc., NeNeww York.York, pppp v,v, 328,328, illustratedillustrated inin colour,colour, notationotationn usedused toto describedescribe crystalscrystals isis explainedexplained andand softcover.softcover. £32.50.£32.50. ISBNISBN 0 471471 156779.15677 9. referrereferredd toto thethe authoritiesauthorities fromfrom whichwhich itit wawass derived:derived: a TheThe bibliographibibliographicc historyhistory ofof thisthis smallsmall simplesimple manualmanual usefuusefull sectionsection onon crystallographiccrystallographic principlesprinciples [adopted[adopted isis almostalmost asas interestinginteresting asas itsits contents!contents! TheThe firstfirst editionedition fromfrom thithiss work]work] explainsexplains ththee useuse ofof systems,systems, classes,classes, MillerMiller waswas publishedpublished nearlynearly 100100 yearsyears agoago andand thethe editionedition indicesindices andand zonezone symbols,symbols, formsforms andand spacespace groups,groups, choicechoice precedingpreceding thethe currentcurrent oneone isis aboutabout 5050 yearsyears old.old. ItIt isis ofof settingssettings [i.e.[i.e. assignmentassignment ofof uniunitt cellcell edgesedges toto thethe axeaxess a,a, pleasingpleasing toto seesee anan oldold friendfriend receivedreceived withwith whawhatt isis bandb and cLc], twinningtwinning andand epitaxy.epitaxy. ThThee choicechoice andand admittedlyadmittedly thethe samesame generalgeneral form.form. TheThe boobookk isis directeddirected

Book Reviews mainlymainly atat thethe amateuramateur andand thethe collectorcollector butbut therethere isis coveragecoverage ofof colourcolour sciencescience withwith manymany featuresfeatures ofof intereinteresstt enoughenough solidsolid materialmaterial forfor thethe gemmologistgemmologist whowho willwill bebe toto thethe gemmologist.gemmologist. SuchSuch readersreaders willwill atat onceonce turnturn toto thethe ableable toto viewview somesome areasareas ofof thethe subjectsubject inin a differentdifferent light.light. editor'seditor's ownown chapterchapter (there(there areare three)three) dealingdealing withwith thethe SomeSome ofof thethe oldold sections,sections, includingincluding thethe useuse ofof thethe fifteenfifteen caucausesess ofof colour:colour: thethe texttext isis understandablyunderstandably basedbased blowpipeblowpipe (not(not SOso easyeasy asas itit sounds!)sounds!) havehave beenbeen retainedretained onon thethe editoreditor''s monographmonograph The Physics and chemichemistrystry ofof butbut moremore up-to-dateup-to-date techniquestechniques ofof mineralmineral testingtesting areare herehere colour (Wiley,(Wiley, 1983).1983). InIn casecase thisthis bookbook isis nownow hardhard toto too,too, togethertogether withwith a newnew chapterchapter onon mineralmineral genesis.genesis. obtain,obtain, readersreaders willwill findfind thethe presentpresent oneone worthworth obtainingobtaining AboutAbout 150150 ofof thethe majormajor speciesspecies areare describeddescribed andand therethere isis forfor thisthis chaptchapteer alone,alone, sincesince thethe colourcolour ofof gemgem materialsmaterials isis a pleasantpleasant centralcentral colourcolour section.section. M.O'D.M.O'D. discusseddiscussed thertheree alongalong withwith a goodgood dealdeal ofof backgroundbackground informationinformation onon colourcolour causes.causes. CulturedCultured Pearls:Pearls: thethe firstfirst hundredhundred years.years. ThisThis coveragecoverage apart,apart, thethe editoreditor hashas alsoalso contributedcontributed chapterschapters onon fundamentalfundamentalss ofof colourcolour science:science: onon a double­double- A.A. MOLLER,MULLER, 1997.1997. GolayGolay BuchelBuchel Group.Group, pppp 142,142, illustratedillustrated blindblind testestt forfor biologicalbiological andand therapeutitherapeuticc effectss ofof colourcolour iinn colour,colour, hardcover.hardcover. US$6O.00.US$60.00. ISBNISBN 4 99006249900624 1 8.8. andand onon colourcolour preservationpreservation,, thithiss sectionsection beinbeingg ofof sspeciapeciall ThisThis welwelll presentedpresented andand richlyrichly illustrateillustratedd bookbook startsstarts interesinterestt ttoo thethe curatorcurator andand archivist.archivist. OtherOther chapterschapters ofof thethe withwith a briebrieff descriptiondescription ofof pearlpearlss inin historyhistory thenthen continuescontinues bookbook dealdeal withwith colourcolour visionvision andand measurement,, colourcolour inin iinn somesome depthdepth onon ththee storystory ofof the culturedcultured pearlpearl,, hohoww itit anthropologyanthropology andand folklore,folklore, iinn plants, animalsanimals andand man,man, camcamee aboutabout anandd whwhoo wawass instrumentainstrumentall iinn itsits developmentdevelopment withwith thethe therapeutitherapeuticc effectseffects ofof lighlightt andand witwithh colourcolour overover ththee paspastt ononee hundrehundredd yearsyears.. TheThe lattelatterr parpartt ooff thethe imaginimagingg andand photography.photography. boobookk describedescribess today'today'ss cultureculturedd ppearlsearls.. ThougThoughh a substantiasubstantiall bookbook,, nono sectionsection ooff iitt cacann hophopee toto ItIt isis notnot a definitivedefinitive workwork anandd the gemmologistgemmologist couldcould serveserve aass anan exhaustivexhaustivee treatmentreatmentt ooff ititss subjectsubject.. FoForr thisthis wiswishh foforr mucmuchh mormoree detaildetail,, bubutt thathatt cancan bbee foundfound reasonreason thethe possiblpossiblee readershireadershipp musmustt havehave beebeenn hardhard toto elsewhereelsewhere.. ThThee authoauthorr himselhimselff statestatess inin ththee foreworforewordd thatthat defindefinee andand inin sucsuchh a casecase ththee publishepublisherr musmustt ensurensuree thethe hhee hahass targetetargetedd a widewide audience andand trietriedd ttoo fillfill a specificspecific mostmost authoritativeauthoritative standardstandardss frofromm contributors.contributors. ThisThis hashas gapgap inin ththee literatureliterature oonn cultureculturedd pearlspearls.. HHee writeswrites certainlycertainly beebeen achievedachieved inin thosethose chapterchapterss onon whicwhichh thisthis factuallyfactually,, bubutt hihiss lovelove ooff ththee subjecsubjectt is ververyy obviousobvious,, andand reviewereviewerr hahass somsomee knowledgknowledgee anandd a readingreading ofof the ththee resulresultt isis aann interestininterestingg andand pleasinpleasingg boobookk whicwhichh wouldwould remainderemainderr ooff thethe textextt suggestsuggestss thathatt a uniformluniformlyy highhigh bbee a goodgood additionaddition ttoo anyany collection.. M.C-PM.e-p.. standardstandard prevailsprevails.. ThThee ratheratherr smalsmalll numbenumberr ofof colourcolour illustrations,, placeplacedd togethetogetherr aatt ththee bacbackk this time, CrystallizationCrystallization.. [Third[Third editionedition)] achieveachievess a faifairr standardstandard bubutt witwithh somesome loss ofof definitiodefinitionn iinn 338 ththee NassaNassauu pictures,, iinn mmyy copcopyy aatt leastleast.. This i s a veryvery JJ.. WW.. MULLINMULLIN,, 1997.1997. ButterwortButterworthh Heinemann,, Oxford.Oxford. smalsmalll mattematterr whewhenn sesett againsagainstt ththee excellencexcellence anandd intintereserestt SoftcoverSoftcover.. £35.00.. ISBISBNN 0 75075066 37537599 55.. ooff ththee textextt anandd ththee carefucarefull citationscitations.. M.O'DM.O'D.. ThThee softcovesoftcoverr issuissuee ooff ththe thirthirdd editioeditionn ooff MullinMullin appearappearss jusjustt aatt a timtimee whewhenn manmanyy ooff ththee standardstandard A Fossicker'Fossicker'ss guidguidee ttoo gemstonegemstoness iinn AustraliaAustralia.. crystallizatiocrystallizationn anandd crystacrystall growtgrowthh texttextss araree abouaboutt duduee forfor NN.. PERRYY ANANDD RR.. PERRYPERRY,, 19971997.. ReeReedd BooksBooks,, KewKew,, Victoria.Victoria. updateupdate.. WhilWhilee ththee emphasiemphasiss hahass alwayalwayss beebeenn onon pppp viiiviii,, 160160,, illustrateillustratedd iinn colourcolour,, softcoversoftcover.. £16.50£16.50.. industriaindustriall crystallizationcrystallization,, thertheree iiss mucmuchh foforr thethe ISBISBNN 0 73073011 000000 88.. mineralogismineralogistt anandd ththee gemmologisgemmologistt ttoo worworkk upouponn anandd thethe earlieearlierr chapterchapterss givgivee a valuablee introductiointroductionn ttoo thethe UpdateUpdatedd editioeditionn ooff a boobookk firsfirstt publishepublishedd iinn 19819822 crystallincrystallinee statestate,, vieweviewedd frofromm a positiopositionn whicwhichh mamayy bbee undeunderr ththee titltitlee A prospector'sprospectvr's guide toto gemstones,gemstones, thithiss guideguide unfamiliaunfamiliarr ttoo eartearthh science-basescience-basedd sstudentstudents.. intendeintendedd foforr ththee amateuamateurr gegemm collectocollectorr iinn AustraliaAustralia describedescribess ththee basibasicc techniquetechniquess ooff fossickinfossickingg [min[minee dumpdump IItt woulwouldd bbee harhardd ttoo over-praisover-praisee ththee luciditlucidityy ooff mucmuchh ooff searching]searching),, ththee evaluatioevaluationn ooff anandd collectincollectingg possibilitiepossibilitiess ooff ththee materialmaterial.. ThThee sectiosectionn oonn solutionss anandd meltmeltss wilwilll helphelp alluvial 1 deposits ,, gemstongemstonee recognitiorecognitionn iinn ththee fieldfield,, detailsdetails ththee readereaderr ttoo understanunderstandd somethinsomethingg ooff ththee processeprocessess ooff AustraliaAustraliann gegemm materialmaterialss anandd aann all-stateall-statess summarsummaryy ooff whicwhichh taktakee placplacee oonn a largelargerr scalscalee iinn ththee EartEarthh anandd ththee gemstongemstonee locationslocations.. ThesThesee introductorintroductoryy sectionsectionss precedprecedee a samsamee cacann bbee saisaidd foforr ththee expositioexpositionn ooff phasphasee equilibria,equilibria, detailedetailedd state-by-statstate-by-statee survesurveyy ooff ththee majomajorr gegemm depositsdeposits:: nucleationucleationn anandd crystacrystall growthgrowth.. TherTheree iiss a 32-page32-page thertheree iiss a glossarglossaryy anandd a shorshortt lislistt ooff referencesreferences.. ThThee boobookk bibliographbibliographyy witwithh ththee emphasiemphasiss oonn industrialindustrial iiss clearlclearlyy writtewrittenn anandd welwelll illustrateillustratedd witwithh bothboth crystallizatiocrystallizationn anandd whilwhilee mucmuchh ooff ththee treatmentreatmentt ooff thethe black-and-whitblack-and-whitee anandd colourecolouredd photographsphotographs:: legalegall notenotess subjecsubjectt iiss inevitablinevitablyy mathematicamathematicall ththee generagenerall levelevell iiss suchsuch araree givegivenn anandd sketcsketchh mapmapss araree plentifuplentifull anandd certainlycertainly thathatt ththee carefucarefull readereaderr witwithh aann interesinterestt iinn gegemm crystalcrystal needed.. AlAlll AustraliaAustraliann gegemm hunterhunterss wilwilll welcomwelcomee thithiss growtgrowlllh wilwilll finfindd ththee boobookk welwelll wortworthh buyingbuying.. M.O'DM.O'D.. accurataccuratee anandd handhandyy guideguide.. M.O'DM.O' D..

ColoColorr foforr sciencescience,, arartt anandd technologytechnology.. ThThee NationaNationall GeGemm CollectionCollection,, SmithsonianSmithsonian KK.. NASSAU,, 19981998.. ElsevierElsevier,, Amsterdam, . pppp xviixvii,, 494911 InstitutionInstitution.. IllustrateIllustratedd iinn colourcolour,, hardcoverhardcover.. US$132.00US$132.00.. JJ.. E.. POSTPOST,, 19971997.. SmithsoniaSmithsoniann InstitutioInstitutionn iinn associatioassociationn ISBISBNN 00 444444 8984898466 88.. witwithh HarrHarryy NN.. AdamsAdams,, IncInc,, NeNeww York,, WashingtoWashingtonn MakinMakingg ththee poinpointt thathatt thertheree iiss stilstilll mucmuchh mormoree ttoo bbee DCDC.. pppp 144144,, landscaplandscapee formatformat,, hardcovehardcoverr (softcov(softcoveerr learnlearntt abouaboutt colourcolour,, ititss productionproduction,, usesuses,, measurementmeasurement available)available),, illustrateillustratedd iinn colourcolour.. £29.00£29.00.. anandd perceptionperception,, ththee authorauthorss combincombinee ttoo producproducee a broabroadd ISBISBNN 00 81081099 36936900 99..

/J.. Gemm., 1998, 26,26, 5,5, 334-339334-339 AfteAfterr a shorshortt introductiointroductionn iinn whicwhichh ththee naturnaturee ooff qualityquality.. OtherwisOtherwisee ththee textextt iiss similasimilarr iinn arrangemenarrangementt ttoo gemstonegemstoness anandd mineralsminerals,, fashioningfashioning,, coloucolourr anandd ththee paspastt editioneditionss anandd ssoo iiss ththee geniageniall anandd sometimessometimes historhistoryy ooff ththee collectiocollectionn araree introducedintroduced,, ththee bookbook combativcombativee stylestyle.. M.O'D.. introduceintroducess historicahistoricall jewelsjewels;; nonott onlonlyy ththee HopHopee diamonddiamond bubutt alsalsoo ththee NapoleoNapoleonn diamondiamondd necklacenecklace,, thethe AntikeAntikerr SchmucSchmuckk vovomm KlassizismuKlassizismuss bibiss zurzur Marie-AntionettMarie-Antionettee earringearringss anandd ththee SpanisSpanishh InquisitioInquisitionn ModerneModerne.. necklacenecklace,, witwithh ththee PortugesPortugesee DiamonDiamondd anandd ththee HookerHooker emeralemeraldd (75.4(75.477 cctt anandd sesett togethetogetherr witwithh diamonds).diamonds). EE.. STRACKSTRACK,, 19981998.. Riihle-DiebeneRiihle-Diebenerr VerlagVerlag,, StuttgartStuttgart., pppp 112112,, illustrated in colour, softcover. DM42.89 including DiamondDiamond,, corunducorundumm anandd beryberyll havhavee ththee nexnextt chapterchapter illustrated in colour, softcover. DM42.89 including ttoo themselvesthemselves,, ththee followinfollowingg sectiosectionn dealindealingg witwithh quartz,quartz, postagpostagee anandd packagingpackaging.. ISSISSNN 0175-565-X0175-565-X.. topaztopaz,, garnetgarnet,, tourmalinetourmaline,, peridotperidot,, zirconzircon,, spinel,spinel, ThThee 111188 colourecolouredd photographphotographss ooff jewellerjewelleryy veryvery chrysoberylchrysoberyl,, spodumenspodumenee anandd tanzanitetanzanite.. PhenomenalPhenomenal pleasinglpleasinglyy illustratillustratee a shorshortt survesurveyy ooff EuropeaEuropeann jewellerjewelleryy gemstonegemstoness (sta(starr stonestoness anandd cat's-eyescat's-eyes)) havhavee theitheirr ownown frofromm 17817899 ttoo ArArtt DecDecoo anandd modermodernn styles.. A googoodd deadeall ooff chapter:: ththee ornamentaornamentall speciespeciess jadejade,, lapilapiss lazuli,lazuli, gemmologicagemmologicall informatioinformationn appearappearss withiwithinn a textextt devoteddevoted turquoisturquoisee anandd malachitmalachitee araree treatetreatedd individually.. iinn ththee maimainn ttoo jewellerjewelleryy foforr GermaGennann speakersspeakers.. IncidentallyIncidentally AppendiceAppendicess covecoverr rarraree anandd unusuaunusuall gemstones,gemstones, ththee boobookk hahass nnoo ISBISBNN numbenumberr aass iitt iiss nonott availableavailable birthstonesbirthstones,, a glossarglossaryy ooff fashioninfashioningg termsterms,, hardnesshardness througthroughh bookshopsbookshops;; iitt cacann bbee obtaineobtainedd onloniyy frofromm thethe valuevaluess foforr ththee mormoree importanimportantt speciesspecies,, diamondiamondd gradinggrading publishepublisherr whwhoo hahass beebeenn allocateallocatedd aann ISSISSNN number.number. anandd a lislistt ooff somsomee ooff ththee mormoree importanimportantt specimenspecimenss iinn thethe M.O'DM.O'D.. collectioncollection.. ThiThiss lislistt appearappearss iinn previoupreviouss guideguidess bubutt iitt hashas ooff courscoursee beebeenn updatedupdated.. EntriesEntries,, alphabeticallalphabeticallyy arranged,arranged, ThThee TheodorTheodoree HorovitHorovitzz LibraryLibrary.. givgivee weightweight,, sourcesource,, donodonorr (wher(wheree importantimportant)) andand museumuseumm accessioaccessionn number.number. [Catalogu[Cataloguee ooff a salsalee helheldd aatt Christie'Christie'ss GenevaGenevall997.] 1997. pppp 4646,, illustrateillustratedd iinn colourcolour,, softcover.softcover. QualitQualityy ooff ththee photographphotographss iiss all-importanall-importantt iinn thisthis kinkindd ooff boobookk anandd foforr ththee ververyy reasonablreasonablee pricpricee ththee qualityquality TheodorTheodoree HorovitzHorovitz,, borbornn iinn RomaniaRomania,, eventuallyeventually iiss goodgood,, thougthoughh variable, ParticularlParticularlyy attractivattractivee araree thethe becambecamee ononee ooff Geneva'Geneva'ss besbestt knowknownn jewellersjewellers.. DurinDuringg hishis picturepicturess ooff kunzitkunzitee (in(in whicwhichh pleochroipleochroicc colourcolourss areare liflifee hhee collectecollectedd a numbenumberr ooff finfinee anandd rarraree bookbookss onon shown),shown), peridotperidot,, topaztopaz,, variously-colourevariously-mlouredd sapphiressapphires andand jewellerjewelleryy andand gemstonesgemstones summarizedsummarized iinn ththee cataloguecatalogue ththee reredd phosphorescencphosphorescencee ofof ththee HopHopee diamond.. TheThe descriptionsdescriptions andand supportesupportedd witwithh severalseveral excellentexcellent collectioncollection isis well-servedwell-served bbyy thithiss excellentexcellent guide.guide. MM.O'D.O'D.. illustrationsillustrations.. M.O'D.M.O'D. 339 A fieldfield guideguide ttoo rocksrocks andand minerals.minerals. [5th[5th edition]edition] Jadeite.Jadeite. 339 F.F. H.H. POUPOUGHGH,, 1996.1996. HoughtonHoughton MifflinMifflin Company,, Boston.Boston. LEELEE YINGYING Ho,HO, 1996.1996. AsiapacAsiapac,, Singapore.Singapore, pppp 126,126, illustratedillustrated ppppxv xv,, 396,396, illustratedillustrated inin colour,colour, softcover.softcover. £10.99.£10.99. inin colour,colour, softcover.softcover. £17.95£17.95.. ISBNISBN 981981 3023029879 87 O.0. ISBNISBN 0 395395 7277772777 4.4. ShortShort butbut beautifullybeautifully illustrateillustratedd surveysurvey ofof jadeitjadeitee andand AccordingAccording toto ththee prefacepreface thisthis excellentexcellent guideguide wawass firstfirst jadeitjadeitee jewellerjewelleryy firstfirst publishepublishedd inin 1991,1991, thethe ChineseChinese texttext publishedpublished 4646 yearsyears agoago butbut whilewhile itit hashas alwaysalways beebeenn oneone nownow translatedtranslated andand accompaniedaccompanied byby illustrationsillustrations takentaken ofof ththee bestbest fieldfield guidesguides andand longlong familiarfamiliar toto allall seriousserious largelylargely fromfrom Sotheby'sSotheby's jadeitjadeitee sales.sales. NoteNotess onon buyingbuying collectors,collectors, thisthis editionedition isis worthworth particulaparticularr mentionmention onon jadeitejadeite,, onon it'sit's simulantssimulants andand treatmentstreatments areare particularlyparticularly accountaccount ofof thethe freshfresh colourcolour photographsphotographs suppliedsupplied byby usefuluseful butbut otherother sections,sections, dealingdealing withwith jadeitjadeitee carvingcarving andand JeffreyJeffrey Scovil. TheyThey areare groupedgrouped togethertogether inin a singlesingle stylesstyles ofof ornamentornament areare alsoalso valuable.valuable. I cancan stronglystrongly sectionsection atat thethe centrecentre ofof thethe bookbook andand areare ofof veryvery highhigh recommendrecommend thisthis bookbook toto allall classesclasses ofof reader.reader. M.O'D.M.O'D.

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Book ReviewsReviews Proceedings of the Gemmological Association and Gem Testing Laboratory of Great Britain and Notices

NEWS OF FELLOWS OBITUARY We are very pleased to report that our Alan Bridgewood (D.1988), Bramhope, Leeds, President Professor R.A. Howie, has recently been West Yorkshire, died suddenly on 10 May 1998. awarded the Distinguished Public Service Award for 1999 by the Mineralogical Society of America. 1999 CALENDAR This is one of their three highest awards, and is for Professor Howie's services to mineralogy - The brooch illustrated for January and particularly his enormous contribution to February in the GAGTL 1999 calendar (see below Mineralogical Abstracts. left) was by David Thomas and not Stephen Webster. We apologize for the error and any Michael O'Donoghue gave a paper on Synthetic embarrassment caused. gemstones at the end of the twentieth century to the Gemmological Association of Hong Kong on 340 21 September 1998 and the same paper to the MEMBERS' MEETINGS Shanghai Gem and Jade Association on London 30 September. On 9 October 1998 at the Gem Tutorial Centre, 27 Greville Street, London EC1N 8TN, Kreg Skully 1960s brooch with gem garnets by David Thomas. from Virginia Beach, USA, gave a talk on Photograph by Bob Maurer, FGA DGA, London. Contemporary Gem Art in America. Kreg creates crafted carvings of stone enclosing gold-bezelled opal freeforms, and he spoke about his own work and that of other contemporary gem artists in North America. On 1 November at the Barbican Centre, London EC2, the GAGTL Conference was held on the theme Gems in Jewellery. This was followed on Monday 2 November by visits to the Victoria and Albert and the Natural History Museums, South Kensington. A full report of the Conference was published in the December issue of Gem and Jewellery News. On 4 November at Imperial College, South Kensington, Dr Kurt Nassau gave a lecture entitled F.F.H. Moissanf Polytypes and Synthetic moissanite. Samples of the new diamond simulant were available for examination.

Midlands Branch On 30 October 1998 at the Earth Sciences Building, University of Birmingham, Edgbaston, Clive Burch gave an illustrated talk on The amazing

© Gemmological Association and Gem Testing Laboratory of Great Britain ISSN: 1355-4565 GIFTGIFTSS T TOO TH THEE ASSOCIATIO ASSOCIATIONN ThThee Associatio Associationn is is mos mostt gratefu gratefull t oto th thee followin followingg fo forr thei theirr gift giftss fo forr researcresearchh an andd teachin teachingg purposes purposes:: RicharRichardd Burto Burtonn fo rfor a nan apatit apatitee (aqu (aquaa blue blue)) fro fromm Mogok Mogok,, Myanmar Myanmar.. DanieDaniell Dower Dower,, London London,, fo forr a asmok smokyy quart quartzz an andd 3 232 piece piecess o fof amber amber.. LuellLuellaa Dykhuis Dykhuis,, Tucson Tucson,, Arizona Arizona,, USA USA,, fo forr a avariou variouss ge gemm material materialss includin includingg quartz quartz,, calcite calcite,, peridoperidott an andd bone bone.. ArthuArthurr Fiewelling Flewelling,, Arthu Arthurr Ontario Ontario,, Canada Canada,, fo forr a acollectio collectionn o fof quart quartzz crystal crystalss frofromm HerkimerHerkimer,, Newew York York. . JohJohnn R .R. Fiihrbach Fuhrbach,, Amarillo Amarillo,, Texas Texas,, U.S.A. U.s.A.,, fo forr a aspecime specimenn o fof smithsonite smith onite,, a asuper superbb Herkime Herkimerr quartquartzz crysta crystall wit withh interestin interestingg inclusions inclusion,, a ahalit halitee fro fromm a alittle-know little-knownn sourc sourcee i nin Mexic Mexicoo an andd a a topa topazz frofromm th thee ne neww min minee in in Colorado Colorado.. ElizabetElizabethh Gage Gage,, London London,, fo forr 5 050 specimen specimenss includin includingg tanzanite tanzanite,, quartz quartz,, firfiree opalopal,, tourmalintourmalinee anandd glassglass.. SonjSonjaa Glaser Glaser,, Galle Galle,, Sr Srii Lanka Lanka,, fo forr 1 515 cu cutt specimen specimenss includin includingg aquamarine aquamarine,, natura naturall an andd synthetisyntheticc spinelspines lans andd hessonit hessonitee garnets garnets.. MarciMarciaa Lanyon Lanyon,, London London,, fo forr a aCD-write CD-writerr fo forr th thee ne neww CD-RO CD-ROMM archivin archivingg an andd productio productionn system system.. JeaJeann Smit Smithh (th (thee lat latee Rober Robertt Webster' Web ters's daughter) daughter),, WesWestt WimbledonWimbledon, , LondonLondon,, foforr Gemme Gemme (in(in Italian Italian)) b yby Rober Robertt Webster Webster.. YasukazYasukazuu Suwa Suwa, Tokyo, Tokyo,, Japan Japan,, fo forr Gemstones Gemstolles quality alldand va valuelue volumes volume s1 1and an d2, 2 with, wit hEnglish Englis h translationstranslations.. PauPaull Thurlby Thurlby,, Birmingha Birminghamm Institut Institutee o fof Ar Artt an andd Design Design,, fo forr a alarg largee collectio collectionn o off coloure colouredd glass glass.. WilmWilmaa va vann de derr Giessen Giessen,, Voorburg Voorburg, Th, Thee Netherlands etherlands,, fo forr a aGilso Gilsonn mosai mosaicc opa opall triplet triplet.. PierrPierree Vuillet Vuillet,, Villard Villardss d'Heria d'Heria,, France France,, fo forr nin ninee specimen specimenss o fof emeral emeraldd replacin replacingg fossi fossill snails snails. . 341 RoberRobertt Wood Wood,, Stamford Stamford,, Lincolnshire Lincolnshir,e, fo forr a aquantit quantityy o fof minera minerall specimens specimens,, a a selectio selectionn o off roug roughh berylsberyl, s,an andd cu cutt stone stoness includin includingg garnet gamet,, ruby ruby,, sapphire sapphire,, syntheti syntheticc spine spinell an andd fir firee opal opal.. YumYumii Yoshitake Yoshitake,, London London,, fo forr a arepor reportt o non Japanes Japanesee culture cu lturded pear pearll wit withh sample sampless o off oyste oy terr shel shelll anandd cultureculturedd pearl pearlss o fof variou variouss qualities qualities.. andand informativeinformative worldworld ofof gemstonegemstone inclusionsinclusions.. The Th e ScottisScottishh Branc Branchh accenaccentt was was o onn geologica geologicall signaturesignaturess o off inclusion inclusionss OOnn 1122 OctobeOctoberr 19919988 aatt ththee BritisBritishh GeologicaGeologicall anandd ththee datdataa availablavailablee indicatinindicatingg formatioformationn anandd SurveySurvey,, MurchisoMurchisonn HouseHouse,, WesWestt MainMainss RoadRoad,, provenancprovenancee o off th thee ge gemm inclusion inclusionss observed observed. . EdinburghEdinburgh,, DaviDavidd LancasteLancasterr gavgavee aa taltalkk entitleentitledd OOnn 2 277 Novembe Novemberr a att th thee Eart Earthh Science Sciencess Buildin Buildingg PointersPointers for valuation.valuation. AlaAlann JobbinJobbinss gavgavee aa taltalkk oonn hihiss GemmologicalGemmological OOnn 1111 NovembeNovemberr aatt ththee BritisBritishh GeologicaGeologicall journeysjourneys inin Brazil,Brazil, coveringcovering thethe pegmatitepegmatite gemsgems ofof SurveSurveyy DDrr KurKurtt NassaNassauu gavgavee aa taltalkk entitleentitledd MinaMinass Gerai Geraiss an andd th thee opal opalss an andd diamond diamondss o off Piaui Piau!.. Gemstones:Gemstones: sciencescience,, synthesis, synthesis, beauty, beauty, deception. deception. OOnn 5 5 Decembe Decemberr th thee 46t 46thh AnnuaAnnuall Dinne Dinnerr wa wass heldheld.. PRESENTATIOPRESENTATIONN O OFF AWARD AWARDSS NortNorthh Wes Westt Branc Branchh ThThee Presentatio Presentationn o off Award Awardss gaine gainedd i nin th thee 199 19988 examinationexaminationss was was hel heldd a att Goldsmiths Goldsmiths'' Hall Hall,, Foste Fosterr OOnn 2 211 Octobe Octoberr 199 19988 a att Churc Churchh House House,, Hanove Hanoverr LaneLane,, Londo Londonn EC2 EC2,, o onn Monda Mondayy 2 2 November November.. Th Thee StreetStreet,, LiverpooLiverpooll 11,, MartiMartinn ConnarConnardd gavgavee aa PresidentPresident,, ProfessoProfessorr R.AR.A.. HowieHowie,, presidepresidedd anandd presentatiopresentationn entitle entitledd Silversmith Silversmith ofof Williamsburg Williamsburg 1780 1780.. welcome welcomedd thosthosee presentpresent.. HHee announceannouncedd thathatt inin OOnn 1 188 Novembe Novemberr a att Churc Churchh Hous Housee th thee Branc Branchh JanuarJanuaryy anandd JunJunee 19919988 aa totatotall ooff 979722 studentstudentss AGAGMM wawass helheldd aatt whicwhichh IrenIrenee KnightKnight,, DeannDeannaa entereenteredd ththee PreliminaryPreliminary,, DiplomDiplomaa anandd GeGemm BradBradyy anandd DDrr JohJohnn FrankFrankss werweree re-electere-electedd DiamonDiamondd ExaminationsExaminations. .A A totatotall ooff 141499 studentstudentss ChairmanChairman,, Secretar Secretaryy an andd Treasure Treasurerr respectively respectively.. passepassedd th thee Diplom Diplomaa examinatio examinationn an andd the theyy cam camee

ProceedingsProceedings and and Notices Notices fromfrom 1818 countries.countries. 106106 studentsstudents passedpassed thethe GemGem DiamondDiamond examinationexamination andand therethere werewere successfulsuccessful candidatescandidates thisthis yearyear fromfrom ninenine countries.countries. 'Here"Here tonight:tonight/ continuedcontinued ProfessorProfessor Howie,Howie, 'we'we havehave successfulsuccessful candidatescandidates fromfrom thethe u.K.U.K. andand EuropeEurope asas wellwell asas thosethose fromfrom Canada,Canada, Japan,Japan, NewNew Zealand,Zealand, SriSri LankaLanka andand thethe U.s.A:U.S.A/ ProfessorProfessor HowieHowie recalledrecalled thatthat atat previousprevious PresentationPresentation ceremoniesceremonies hehe hadhad talkedtalked aboutabout hardnesshardness andand itsits importanceimportance toto mineralogistsmineralogists andand gemmologists.gemmologists. 'Tonight',Tonight7, hehe said,said, 'IT wantwant ttoo spendspend a fewfew momentsmoments talkingtalking aboutabout carborundum.carborundum. HavingHaving beenbeen broughbroughtt upup onon a farm,farm, I becamebecame acquaintedacquainted withwith allall mannermanner ofof devicesdevices useusedd forfor sharpeningsharpening scythescythe bladesblades,, andand thethe bladesblades oror "knives""knives" ofof mowingmowing machinemachiness andand harvestingharvesting machines.machines. SuchSuch sharpeningsharpening stones,stones, oror whetstones,whetstones, rangedranged fromfrom sandstonesandstone toto fine-grainedfine-grained metamorphicmetamorphic rockrockss oror hornstones,hornstones, butbut thesethese werewere mostlymostly supplantedsupplanted byby bondebondedd carborundum.carborundum. CarborunduCarborundumm wawass firstfirst manufacturedmanufactured inin 18931893 andand waswas soso namednamed becausebecause itit waswas originallyoriginally believedbelieved toto bebe a compoundcompound ofof carboncarbon andand aluminium.aluminium. ItIt isis Diploma Trade Prize winner Tina Notaro fromfrom commonlycommonly bluisbluishh greygrey whenwhen bondedbonded,, butbut Madison, U.S.A., receiving her prize. materialmaterial produceproducedd asas slagslag fromfrom electricelectric furnacesfurnaces hahass brighbrightt blueblue toto greenishgreenish colourscolours witwithh a veryvery curators,curators, theythey willwill telltell youyou thatthat oneone ofof thethe mostmost highighh lustre.lustre. IndeedIndeed ifif oneone talkstalks toto museummuseum 342 frequentfrequent "unknowns""unknowns" broughtbrought inin bbyy ththee generalgeneral $42 publicpublic forfor identificationidentification isis coarse-grainedcoarse-grained Tully Medal and Anderson Bank Prize winner Laurent lustrouslustrous carborundum.carborundum. Kellerson from London, receiving his awards from 'It'It waswas foundfound laterlater thatthat carborundumcarborundum waswas inin Robin Buchanan-Dunlop.Buchanan-Dunlop. factfact a compoundcompound ofof carboncarbon andand silicon,silicon, SiC,SiC, andand asas suchsuch materialmaterial hadhad beenbeen describeddescribed inin 19041904 frofromm thethe CanyonCanyon DiabloDiablo meteoritemeteorite inin Arizona,Arizona, thethe mineralmineral SiCSiC waswas namednamed moissanitemoissanite afterafter thethe FrenchmanFrenchman whowho firstfirst describeddescribed it.it. ItIt is,is, however,however, extremelyextremely rarerare,, andand isis notnot representedrepresented inin mostmost museummuseum collectionscollections.. IndeedIndeed iinn thethe decadedecade aroundaround 1960,1960, manymany scientificscientific paperspapers werewere produceproducedd arguingarguing thatthat thethe identificationidentification ofof thethe occasionaloccasional grainsgrains maymay havehave beenbeen correctcorrect butbut thatthat inin factfact theythey representedrepresented contaminationcontamination fromfrom grindinggrinding materialsmaterials useusedd toto prepareprepare thethe thinthin sectionssections forfor microscopicmicroscopic examination.examination. TheThe 19971997 editionedition ofof Dana's NewNew Mineralogy, thethe mineralogist'smineralogist's biblebible,, forfor exampleexample observesobserves thatthat moissanitmoissanitee waswas "originally"originally describeddescribed fromfrom thethe CanyonCanyon DiabloDiablo meteoritemeteorite,, bubutt isis probablyprobably a contaminant".contaminant". However,However, moissanitemoissanite isis nownow acceptedaccepted asas a veryvery rarerare naturalnatural mineralmineral speciesspecies foundfound inin somesome meteoritesmeteorites andand inin kimberliteskimberlites andand asas eveneven asas inclusionsinclusions inin diamonds.diamonds. ButBut itit isis stillstill extremelyextremely rare,rare, occurringoccurring inin amountsamounts ofof aroundaround 0.0010.001 perper centcent inin rocksrocks thatthat areare themselvesthemselves rare.rare. 'With'With thethe brilliantbrilliant lustrelustre andand brightbright colourscolours shownshown bbyy carborundum,carborundum, I mustmust confessconfess thatthat forfor somesome yearsyears I havehave beenbeen expectingexpecting a newnew syntheticsynthetic

J./. Gemm., 1998,1998,26, 26, 5, 340-347340-347 gegemm ttoo bbee produceproducedd frofromm siliconsilicon carbidecarbide -- however,however, I waswas thinkinthinkingg iinn termsterms ofof aann attractive,attractive, lustrouslustrous,, greenish-bluegreenish-blue oorr blueblue stonestone ttoo simulatesimulate somesome ofof ththee corunducorundumm familyfamily ooff gemsgems.. ButBut thisthis neneww materiamateriall currentlycurrently callecalledd syntheticsynthetic moissanitemoissanite iiss virtuallyvirtually colourlesscolourless anandd water-clearwater-clear,, withwith hardneshardnesss 9;1,9% anandd highhigh dispersion.dispersion. ItsIts manufacturersmanufacturers (C3(C3 Inc.)Inc.) claimclaim thathatt iitt iiss nonott meantmeant toto simulatesimulate diamond,diamond, bubutt merelymerely toto offeroffer a reasonablyreasonably cheapcheap stonestone forfor incorporatioincorporationn intointo jewellerjewelleryy atat aann attractiveattractive priceprice.. WWee shallshall see.see. CertainlyCertainly ththee "synthetic""synthetic" parpartt ooff ththee namename mustmust nevernever bbee droppeddropped bubutt mustmust bbee usedused foforr eacheach andand evereveryy mentiomentionn ofof thithiss materialmaterial.. HoweverHowever,, ththee gemgem tradetrade hashas gotgot useusedd toto thethe tertermm CZCZ asas a shorthandshorthand namename foforr cubicubicc zirconizirconiaa (t(too distinguishdistinguish thisthis materialmaterial frofromm naturalnatural zirconia,zirconia, baddeleyitebaddeleyite,, whichwhich isis monoclinic)monoclinic).. SoSo whwhyy notnot callcall thithiss materiamateriall simplysimply SiCSiC - oror eveneven CC33 asas opposeopposedd ttoo CZ.CZ. I wilwilll leaveleave youyou toto thinthinkk oonn thesethese things!things! 'You'You mamayy nonott havehave yeyett seenseen thithiss newestnewest "fashionable""fashionable" stonestone butbut,, aass trainedtrained gemmologists,gemmologists, youyou shouldshould findfind thathatt youryour trainintrainingg iinn observationobservation witwithh a lenslens anandd iinn thethe measuremenmeasurementt ooff specificspecific Preliminary Trade Prize winner Linda Rythen from gravitgravityy leavesleaves youyou amplamplyy equippeequippedd ttoo dealdeal withwith it;it; Stockholm, Sweden, receiving her award. itit isis doublydoubly refractivrefractivee anandd floatsfloats iinn methylenemethylene iodidiodidee (as(as I stillstill calcalll it;it; perhapperhapss diodomethanediodomethane oror emissioemISSIOnn - I aamm afraiafraidd youyou araree goinggoing ttoo bebe jusjustt CHCHzI2I2 ttoo you)you).. YourYour trainintrainingg iinn fundamentalsfundamentals z disappointeddisappointed!! InsteaInsteadd I wantwant ttoo taltalkk brieflybriefly aboutabout 343 wilwilll standstand youyou inin goodgood steadstead anandd hopefullhopefullyy willwill ththee historhistoryy andand romancromancee ofof precioupreciouss stones.stones. PartPart ooff providprovidee youyou witwithh ththee meansmeans toto dealdeal witwithh whateverwhatever ththee fascinationfascination ooff precioupreciouss stonesstones isis notnot jusjustt thatthat thethe tradtradee comescomes uupp withwith iinn ththee futurefuture - anandd eveevenn toto thetheyy areare beautifulbeautiful,, rarraree andand expensiveexpensive,, bubutt behindbehind makemake newnew discoveries:discoveries/ themthem lieliess anan age-oldage-old historyhistory ofof myth,myth, love,love, hatehate ProfessoProfessorr HowiHowiee thethenn introducedintroduced RobinRobin andand intrigue.intrigue. IfIf yoyouu areare explorinexploringg thethe historhistoryy ooff Buchanan-Dunlop,Buchanan-Dunlop, ClerkClerk ooff thethe WorshipfulWorshipful precioupreciouss stonesstones aass jewelsjewels,, thethenn iitt isis possiblpossiblee withwith a CompanyCompany ooff Goldsmiths,Goldsmiths, whwhoo presentedpresented thethe littlelittle imaginatioimaginationn ttoo reachreach outout andand touchtouch thatthat awardsawards.. M Mrr Buchanan-DunloBuchanan-Dunlopp deliveredeliveredd hishis history.history. addresaddresss (se(seee belowbelow)) anandd a votevote ooff thanksthanks waswas givengiven 'Le'Lett uuss startstart withwith mmyy grandfathegrandfatherr (well(well,, ononee hashas bbyy ViviaViviann Watson.Watson. toto startstart somewhere).somewhere). HHee foughfoughtt inin thethe BoeBoerr WarWar ProfessoProfessorr HowieHowie concludeconcludedd ththee proceedingsproceedings andand FirsFirstt WorlWorldd WarWar,, whicwhichh iiss ooff littlelittle consequence.consequence. bbyy thankingthanking ththee Goldsmiths'Goldsmiths' CompanCompanyy forfor ButBut hhee waswas borbornn iinn 1876.1876. YoYouu mamayy finfindd nothingnothing kindlykindly permittinpermittingg thethe GAGTLGAGTL ttoo holholdd thethe remarkableremarkable aboutabout thatthat datedate.. BuButt iiff I werweree ttoo teltelll youyou ceremonyceremony atat ththee Hall.Hall. thatthat thatthat waswas thethe yearyear iinn whichwhich AlexanderAlexander BellBell submittesubmittedd a patenpatentt forfor a telephonetelephone;; thathatt itit wawass thethe yeayearr inin whicwhichh ththee OttoOtto engine,engine, ththee firstfirst practicalpractical RobiRobinn Buchanan-Dunlop'sBuchanan-Dunlop's addressaddress internalinternal combustioncombustion enginenginee inin generagenerall useuse,, waswas ''II aamm delightedelightedd ttoo bbee herehere tonighttonight ttoo presentpresent introduced;introduced; thathatt itit wawass ththee yeayearr iinn whicwhichh electricelectric thesethese awards,awards, bubutt I ddoo soso witwithh a littllittlee trepidation,trepidation, lightlight startestartedd ttoo bbee useusedd aass a publipublicc utilityutility;; thethenn youyou becausbecausee althoughalthough I aamm luckluckyy enoughenough toto workwork mightmight changechange youryour mind.mind. TheThe motomotorr cacarr anandd thethe surroundedsurrounded bbyy golgoldd andand silversilver anandd jewelsjewels,, I knowknow airplaneairplane hadhad stilstilll ttoo bbee invented,invented, notnot toto mentionmention veryvery littlelittle aboutabout gemmologygemmology.. A littlelittle knowledgeknowledge isis thethe siliconsilicon chipchip,, bubutt arguablyarguably iitt wawass ththee dawndawn ooff a dangerousdangerous thing,thing, andand I learntlearnt sometimesometime agoago thatthat modernmodern civilizatiocivilizationn asas wwee araree accustomedaccustomed toto itit today. iitt iiss eveevenn mormoree dangerousdangerous toto displadisplayy one'sone's today. ignorancignorancee iinn ththee compancompanyy ofof expertsexperts.. SoSo iiff youyou areare 'Forty-on'Forty-onee yearyearss beforbeforee hehe waswas borbornn yoyouu couldcould expectingexpecting a learnedlearned dissertationdissertation onon heatheat treatmenttreatment havhavee beebeenn sittingsitting herehere foforr thethe grandgrand dinnerdinner toto oorr radiatioradiationn oorr analysisanalysis bbyy proton-induceproton-inducedd X-rayX-ray celebratecelebrate ththee openinopeningg ooff Goldsmiths'Goldsmiths' HalHalll inin 18351835..

Proceedings and and Notices Notices youyou maymay bebe wonderingwondering wherwheree I amam takingtaking you.you. HaveHave patience!patience! WeWe areare nownow atat thethe limitlimit ofof so-calledso-called modemmodern history,history, soso letlet usus leapleap backback 15001500 yearsyears toto thethe SinaiSinai DesertDesert wherewhere thethe childrenchildren ooff IsraelIsrael havinghaving escapedescaped fromfrom EgyptEgypt areare journeyinjourneyingg toto thethe PromisePromisedd Land.Land. AndAnd youyou willwill recallrecall thatthat GodGod commandedcommanded MosesMoses toto buildbuild a tabernacle,tabernacle, andand therethere waswas ttoo bebe a HighHigh Priest,Priest, Aaron,Aaron, andand hehe wawass ttoo havehave a breastplatebreastplate ofof beatenbeaten gold,gold, andand setset intointo thatthat breastplatebreastplate inin mountingsmountings ofof goldgold werewere toto bbee fourfour rowsrows ofof precioupreciouss stones:stones: thethe firstfirst row:row: a sardius,sardius, a topaztopaz andand a carbuncle;carbuncle; secondsecond row:row: anan emerald,emerald, a sapphiresapphire andand a diamond;diamond; thirdthird row:row: a ligure,ligure, anan agateagate andand anan amethyst;amethyst; fourthfourth row:row: a berylberyl,, anan onyxonyx andand a jasperjasper.. TheyThey presentpresent anan interestinginteresting mixturemixture onon whatwhat thethe earlyearly recordersrecorders ofof historyhistory regardedregarded asas importanimportantt preciousprecious stones.stones. 'Come"Come forwardforward againagain inin timetime jusjustt overover 15001500 yearsyears andand wewe havehave thethe firstfirst recordrecord ofof thethe Koh-i-NoorKoh-i-Noor Diamond,Diamond, thethe MountainMountain ofof Light,Light, whichwhich waswas acqUiredacquired inin 13041304 byby thethe SultanSultan Ala-ed-din.Ala-ed-din. EventuallEventuallyy itit waswas toto bebe presentedpresented toto QueenQueen VictoriaVictoria andand displayeddisplayed inin thethe GreatGreat ExhibitionExhibition ofof 1851185l.. 'TheThe fascinationfascination ofof preciousprecious stonesstones hashas providedprovided manymany anan authorauthor withwith inspiration.inspiration. ItIt waswas Robin Buchanan-Dunlop speaking at Goldsmiths' Hall believedbelieved atat oneone timetime toto havehave beenbeen thethe eyeeye ofof anan idolidol 344 inin a templetemple inin anan islandisland inin Mysore.Mysore. ThisThis maymay havehave givengiven WilkieWilkie CollinsCollins thethe ideaidea forfor hishis boobookk The The room would have been lit by candlelight, but The room would have been lit by candlelight, but Moonstone, publishedpublished inin 18681868 whichwhich isis widelywidely from the four chandeliers only because the central from the four chandeliers only because the central regardedregarded asas ththee firstfirst detectivedetective story.story. IfIf youyou areare a fanfan chandelier was a later addition, being one of the chandelier was a later addition, being one of the ofof JameJamess BondBond yoyouu willwill rememberremember IanIan Fleming'sFleming's first gas chandeliers in the country. The colour first gas chandeliers in the country. The colour Diamonds are Forever, nownow immortalizedimmortalized bbyy DeDe scheme would have been in the chaste colours of 7 scheme would have been in the chaste colours of Beers'Beers famoufamouss slogan.slogan. whitewhite andand creamcream andand bufbufff pickepickedd outout inin gold.gold. TheThe The romance of the past is still with us today, colourscolours yoyouu seesee todaytoday werewere a latelate VictorianVictorian The romance of the past is still with us today, but so is ignorance, deception and greed. And just concoction.concoction. ThereThere wouldwould havehave beenbeen nono royalroyal but so is ignorance, deception and greed. And just as we here at Goldsmiths' Hall believe that portraits.portraits. QueenQueen VictoriaVictoria hadhad yetyet toto ascendascend thethe as we here at Goldsmiths' Hall believe that hallmarking protects both the consumer and the throne,throne, andand sheshe diddid notnot meetmeet PrincePrince AlbertAlbert forfor thethe hallmarking protects both the consumer and the honest trader, so knowledge and expertise in firstfirst timetime untiluntil thethe followingfollowing yeayearr inin 1836.1836. QueenQueen honest trader, so knowledge and expertise in gemmology has never been more important in our AdelaideAdelaide inin thethe centrecentre waswas certainlycertainly WilliaWilliamm IIV'sV s gemmology has never been more important in our trade. consortconsort atat thethe time,time, butbut sheshe hadhad yetyet toto presenpresentt herher trade. portraiportraitt toto thethe Company.Company. AndAnd upup herehere atat thethe toptop TheThe partpart whicwhichh thethe GemmologicalGemmological AssociationAssociation tabletable givinggiving a speech,speech, insteadinstead ofof me,me, yoyouu wouldwould andand GemGem TestingTesting LaboratoryLaboratory ofof GreatGreat BritainBritain playsplays havehave seenseen thethe DukeDuke ofof Wellington,Wellington, a greatgreat nationalnational inin makingmaking thisthis happenhappen isis significant,significant, notnot onlyonly inin herohero fromfrom thethe BattleBattle ofof WaterlooWaterloo exactlyexactly twentytwenty ourour domesticdomestic tradetrade butbut asas tonight'stonight's awardsawards havehave yearsyears earlier.earlier. demonstrateddemonstrated throughoutthroughout thethe internationalinternational 'ThisThis waswas thethe thirdthird HallHall onon thisthis site.site. WhenWhen thethe avenuesavenues asas well.well. WhenWhen I visitedvisited thethe GemGem TestingTesting firstfirst HallHall whichwhich waswas acquiredacquired shortlyshortly afterafter thethe LaboratoryLaboratory thethe otherother dayday I waswas toldtold thatthat 6060 perper Goldsmiths'Goldsmiths7 CompanyCompany receivereceivedd itsits firstfirst chartercharter inin centcent ofof ththee studentsstudents camecame fromfrom overseas,overseas, andand thatthat 1327,1327, EnglandEngland wawass inin thethe gripgrip ofof thethe 100100 YearsYears WarWar isis a remarkableremarkable figure.figure. withwith France,France, andand thethe BlackBlack DeathDeath hadhad yetyet toto sweepsweep 'Finally,'Finally, I shouldshould likelike toto congratulatecongratulate thethe awayaway a thirdthird ofof thethe population.population. awardsawards winnerswinners onceonce again.again. I hopehope whateverwhatever youyou 'One'One hundredhundred yearsyears earlierearlier inin 1227,1227, thatthat greatgreat dodo nextnext andand whereverwherever itit is,is, yoyouu willwill enjoyenjoy beingbeing anan warlordwarlord GenghisGenghis KhanKhan whowho drovedrove hishis armiesarmies importantimportant partpart ofof thisthis greatgreat jewellerjewelleryy trade.trade. acrossacross AsiaAsia toto thethe gatesgates ofof ViennaVienna died.died. ByBy nownow SomeoneSomeone onceonce saidsaid thatthat therethere areare fourfour essentialessential

/J.. Gemm., 1998,26,5,340-3471998,26, 5, 340-347 FORTHCOMINFORTHCOMINGG EVENTEVENTSS 2929 Januar Januaryy MidlandMidlandss Branch Branch.. Brin Bringg an andd BuBuyy followefollowedd bbyy QuizQuiz.. 2121 Februar Februaryy ScottisScottishh Branch Branch.. Gemston Gemstonee photograph photographyy course course.. ClivClivee BurcBurchh anandd JohJohnn HarriHarriss 2626 Februar Februaryy MidlandMidlandss Branch Branch.. Cameo Cameoss an andd gemstonegemstoness carvings carvings.. DaviDavidd CallaghaCaJJaghann 1111 Marc Marchh LondonLondon.. Som Somee curren currentt problem problemss iinn diamondiamondd researchre earch.. DDrr HH.. JuditJudithh MilledgeMilledge.. 1717 Marc Marchh ScottisScottishh Branch Branch.. Diamond Diamondss fro fromm ththee crus crustt t oto ththee corecore.. DDrr JefJefff HarriHarriss 1717 Marc Marchh NortNorthh Wes Westt Branch Branch.. Exoti Exoticc diamonds diamonds.. Keit Keithh MasoMasonn 2626 Marc Marchh MidlandMidlandss Branch Branch. Jewel. Jewelss i nin th thee hand hand. .Jame Jamess GoslinGoslingg 3030 Apri Aprill MidlandMidlandss Branch Branch.. I D1D challeng challengee an andd AG AGMM 3030 Apri Aprill ScottisScottishh Branch Branch.. Annua Annuall Conferenc Conferencee an andd AGM AGM.. toto 2 2Ma Mayy GuesGuestt speake speakerr D Drr W.W W.W.. HannemaHannemann 1414 Ma Mayy LondonLondon.. Shinin Shiningg example exampless - - ththee teachinteachingg potentiapotentiall ooff aa gemmologist'gemmologist'ss jewejewell box. Cecilia Pople box. Cecilia Pople 19 May North West. Pearls - romance and fact. Rosamond Clayton 19 May North West. Pearls - romance and fact. Rosamond Clayton 23 May Midlands Branch. Gem Club - Jet. Peggy Hayden 23 May Midlands Branch. Gem Club - Jet. Peggy Hayden 26 June Midlands Branch. Summer supper 26 June Midlands Branch. Summer supper 28 June London. Annual General Meeting, Reunion of Members and Bring a.nd Buy 28 June LondonSale . Annual General Meeting, Reunion of Members and Bring and Buy 14 July SalLondon.e Demantoid garnet and other new gems and minerals from amibia. 14 July LondonProfessor. Demantoi Peter R. dSimp garne ont and other new gems and minerals from Namibia. Professor Peter R. Simpson For further information on the above events contact: For further information on the above events contact: London: Mary Burland on 0171 4043334 London: Mary Burland on 0171 404 3334 Midlands Branch: Gwyn Green on 0121 445 5359 345 Midlands Branch: Gwyn Green on 0121 445 5359 345 orth West Branch: Deanna Brady on 0151 6484266 North West Branch: Deanna Brady on 0151 648 4266 Scottish Branch: Catriona McInnes on 01316672199 Scottish Branch: Catriona Mclnnes on 0131 667 2199 GAGTL WEB SITE For up-to-the-minuteGAGT informationL WEB SITE on GAGTL events For up-to-the-minutvisit our web sitee informatio on www.gagt1.ac.uklgagtln on GAGTL event s visit our web site on www.gagtl.ac.uk/gagtl ingredientingredientss ttoo a happhappyy life:life: ttoo worworkk withwith nicnicee FrenchFrench,, Thomas,Thomas, Knaphill,Knaphill, Woking,Woking, Surrey.Surrey. 19919988 peoplepeople,, ttoo eateat withwith nicenice people,people, ttoo drindrinkk witwithh nicnicee GaoGao,, PengPeng,, Guangdong,Guangdong, P.R.P.R. ChinaChina.. 19919988 people,people, anandd ttoo gogo toto bebedd witwithh a clearclear conscience!conscience! I GudmundsonGudmundson,, IngerInger,, Lit,Lit, Sweden.Sweden. 19919988 wishwish youyou everyevery ononee ooff thosethose ingredients:ingredients/ Ikebe,Ikebe, EmiEmi,, LondoLondon.n . 19981998 LamLam LaLaii ChunChun,, Kowloon,Kowloon, HongHong KongKong.. 19919988 LeeLee ChunChun Man,Man, CentralCentral,, HonHongg KongKong.. 19919988 MEETINGMEETINGSS OOFF THETHE COUNCIL COUNCIL OF OF LeeLee YinYin WaWa,, Kowloon,Kowloon, HongHong KongKong.. 19919988 MANAGEMENMANAGEMENTT LiangLiang Weizhang,Weizhang, Guangzhou,Guangzhou, P.RP.R.. ChinaChina.. 19919988 AAtt a meetingmeeting ooff ththee CounciCouncill ooff ManagementManagement LiyingLiying FanFan,, Shanghai,Shanghai, P.RP.R.. ChinaChina.. 19919988 helheldd atat 2277 GrevilleGreville Street,Street, LondonLondon EClNEC1N 8TN8TN onon 2828 MaddisonMaddison,, StevenSteven J.J.,, Benfieet,Benfleet, Essex.Essex. 19919988 OctobeOctoberr 19981998 ththee businesbusinesss transactetransactedd includedincluded thethe Nunn-WeinbergNunn-Weinberg,, Danielle,Danielle, TorontoToronto,, Ont.,Ont., Canada.Canada. electionelection ofof thethe following:following: 19981998 OkamotoOkamoto,, ChizukoChizuko,, Kochi,Kochi, JapanJapan.. 19919988 OnoOno,, Shiho,Shiho, Tama-City,Tama-City, Tokyo,Tokyo, JapanJapan.. 19919988 Fellowship(FGA)Fellowship(FGA) Plitsi,Plitsi, CatherineCatherine,, LarissaLarissa,, GreeceGreece.. 19919988 Amor,Amor, MirandaMiranda E.,E., Taunton,Taunton, Somerset.Somerset. 19919988 Segelken,Segelken, Christine,Christine, NortNorthh Vancouver,Vancouver, BCBC,, ChoCho KaKa WahWah,, NeNeww TerritoriesTerritories,, HongHong KongKong.. 19919988 CanadaCanada.. 19919988

Proceedings andand NoticesNotices GEGEMM TUTORIATUTORIALL CENTRCENTREE 2277 GrevillGrevillee StreetStreet,, LondoLondonn EC1ECINN 8T8TNN

1177 Februar Februaryy RUBRUBYY ANANDD SAPPHIRSAPPHIREE -- THTHEE INSIDINSIDEE STORSTORYY AA dadayy lookinlookingg aatt alalll aspectaspectss ooff rubrubyy anandd sapphiresapphire:: naturalnatural,, treated,treated, synthetisyntheticc an andd imitationimitation.. PricePrice £104 ++ VAT VAT (£122.20) (£122.20) -inc/udes - Includes a sandwich a sandwich lunch lunch

2244 Februar Februaryy EMERALDEMERALDSS TODATODAYY AA dadayy lookinlookingg aatt alalll aspectaspectss ooff emeraldemerald:: naturalnatural,, treatedtreated,, synthetisyntheticc andand imitationimitation. . PricePrice £104 ++ VATVAT (£122.20) (£122.20) - lnc/udes- Includes a sandwich a sandwich lunch lunch

33 Marc Marchh ORGANICORGANICSS -- AMBERAMBER,, IVORYIVORY,, JETJET,, PEARPEARLL ANANDD SHELLSHELL AAnn opportunit opportunityy t oto loo lookk a att thes thesee organi organicc materialsmaterials,, ththee besbestt wawayy ttoo identifyidentify thethemm an andd thei theirr mos mostt commo commonn imitationsimitations.. PricePrice £104 ++ VAT VAT (£122.20) (£122.20) - Incllld - Includeses a sandwich a sandwich lunch lunch

1177 Marc Marchh DIAMONDDIAMONDSS TODATODAYY 3462Afc I AA valuabl valuablee an andd concentratedconcentrated loolookk aatt alalll aspectaspectss ooff diamondsdiamonds:: rougroughh andand ' cucutt stonesstones,, treatetreatedd (lase(laserr drilledrilledd anandd filled)filled),, synthetisyntheticc anandd imitatioimitationn materialsmaterials. . PricePrice £104£104 ++ VATVAT (£122.20) (£12220) - -Includes Includes a sandwicha sandwich lunch lunch

2424 Marc Marchh EVERYDAEVERYDAYY LIFLIFEE - - TREATMENTTREATMENTSS ANANDD SYNTHETICSYNTHETICSS AA loo lookk a att th thee synthetic synthetic,, imitatio imitationn an andd treate trea tedd material materialss encountere encounteredd iinn ththee jewellerjewelleryy tradtradee todaytoday.. ThThee courscoursee willwill concentratconcentratee oonn emeraldemerald,, rubyruby,, sapphirsapphiree an andd diamond diamond,, emphasizin emphasizingg observatio observationn techniquestechniques.. PricePrice £80£80 + VAT (£94.00)(£94.00) - -Includes Includes a sandw a sandwichich lunch lunch

STUDENSTUDENTT WORKSHOPWORKSHOPSS PreliminarPreliminaryy Theor Theoryy Revie Revieww 2266 ApriAprill Three-day Preliminary Workshop 26 to 28 April Three-day Preliminary Workshop 26 to 28 April Diploma Theory Review 17 May Diploma Theory Review 17 May Four-day Diploma Workshop 17 to 20 May Four-day Diploma Workshop 17 to 20 May Weekend Diamond Grading Revision 5 and 6 June Weekend Diamond Grading Revision 5 and 6 June Two-day Diploma Practical Workshop 5 and 6 June Two-day Diploma Practical Workshop 5 and 6 June For further details contact the GAGTL Education Department For further details contact the GAGTL Education Department Tel: +44 (0)171 4043334 Fax: +44 (0)171 4048843 Tel: +44 (0)171 404 3334 Fax: +44 (0)171 404 8843

J. Gemm., 1998, 26, 5, 340-347340-347 Smits,Smits, CynthaCyntha A.N.,A.N., AlphenAlphen aida/d Rijn,Rijn, ThThee FellowshipFellowship (FGA)(FGA) NetherlandsNetherlands.. 19981998 Darcy,Darcy, JohnJohn P,P, Dublin,Dublin, Ireland.Ireland. 19719799 Song,Song, Ruohan,Ruohan, Shanghai,Shanghai, P.RRR. China.China. 19981998 Rowe,Rowe, LeonardLeonard James,James, Croydon,Croydon, Surrey.Surrey. 19719744 Stratton,Stratton, Claire,Claire, London.London. 19981998 vanvan derder Giessen,Giessen, Wilma,Wilma, Voorburg,Voorburg, ThThee WangWang Shu-Ying,Shu-Ying, Taipei,Taipei, Taiwan,Taiwan, RO.R.O. China.China. 19981998 NetherlandsNetherlands.. 19819855 WatsonWatson Mendis,Mendis, AlexandraAlexandra E.,E., Toronto,Toronto, Ontario,Ontario, Canada.Canada. 19981998 Yahampath,Yahampath, Hirosha,Hirosha, Maharagama,Maharagama, SriSri Lanka.Lanka. DiamondDiamond MembershipMembership (DGA)(DGA) 19981998 Smith,Smith, Colin,Colin, Teddington,Teddington, MiddlesexMiddlesex.. 19919988 Yeung,Yeung, Michelle,Michelle, Toronto,Toronto, Ont.,Ont., Canada.Canada. 19981998 YipYip LianaLiana ChingChing Ying,Ying, NortNorthh York,York, Ontario,Ontario, OrdinaryOrdinary MembershipMembership Canada.Canada. 19981998 ZouZou HonHon WahWah Coral,Coral, HongHong Kong.Kong. 19981998 Kilian,Kilian, AngelaAngela MariaMaria c.,C, Leidschendam,Leidschendam, ThThee NetherlandsNetherlands DiamondDiamond MembershipMembership (DGA)(DGA) Sullivan,Sullivan, BrendaBrenda,, LondonLondon ChanChan YukYuk YeeYee May,May, Kowloon,Kowloon, HongHong Kong.Kong. 19981998 Clancy,Clancy, Jo,Jo, London.London. 19919988 TransferTransfer fromfrom FGAFGA ttoo FGAFGA DGADGA DeDe Souza,Souza, SuzanneSuzanne P.,P., Walton-on-Thames,Walton-on-Thames, Deer,Deer, Georgina,Georgina, Salford,Salford, Lancashire.Lancashire. 19919988 Surrey.Surrey. 19981998 Howard,Howard, Christine,Christine, Sevenoaks,Sevenoaks, Kent.Kent. 19981998 TransferTransfer fromfrom OrdinaryOrdinary MembershipMembership Uhlin,Uhlin, ChristopheChristophe R,R., Leytonstone,Leytonstone, London.London. 19981998 YamYam YauYau Shun,Shun, HongHong Kong.Kong. 19981998 toFGAto FGA Kellerson,Kellerson, LaurentLaurent P.,P., London.London. 19981998 OrdinaryOrdinary MembershipMembership fillili347! Audretsch,Audretsch, EvelynEvelyn A.,A., Aberdeen,Aberdeen, ScotlandScotland Burton,Burton, MarkMark G.,G., Guildford,Guildford, SurreySurrey Museums,Museums, Candengue,Candengue, DomingosDomingos M.,M., Streatham,Streatham, LondonLondon EducationalEducational Establishments,Establishments, Choi,Choi, SunSun YoungYoung Chun,Chun, Yangon,Yangon, MyanmarMyanmar CollectorsCollectors & StudentsStudents Delamater,Delamater, Laurel,Laurel, Chesterton,Chesterton, CambridgeCambridge Jonson,Jonson, CatalinaCatalina c.,C, StSt John'sJohn's Wood,Wood, LondonLondon I havehave whatwhat isis probablyprobably thethe largestlargest rangerange Lee,Lee, PohPoh Heong,Heong, StSt John'sJohn's Wood,Wood, LondonLondon ofof genuinelygenuinely rarerare stonesstones inin thethe UK,UK, fromfrom MossutoMossuto Mori,Mori, E.E. Maria,Maria, Yangon,Yangon, MyanmarMyanmar AnalcimeAnalcime ttoo Wulfenite.Wulfenite. AlsoAlso rarerare andand Patel,Patel, VirendraVirendra T.,T., NorburyNorbury,, LondonLondon modemmodern synthetics,synthetics, andand inexpensiveinexpensive Roberts,Roberts, KennethKenneth H.,H., LondonLondon crystalscrystals andand stonesstones forfor students.students. NewNew Shahdadpuri,Shahdadpuri, NeetaNeeta D.,D., StSt John'sJohn's Wood,Wood, LondonLondon computerisedcomputerised listslists availableavailable withwith eveneven Soe,Soe, Myint,Myint, Yangon,Yangon, MyanmarMyanmar moremore detail.detail. PleasePlease sendsend £2£2 inin 11sst t classclass Walters,Walters, Belinda,Belinda, Horsham,Horsham, SussexSussex stampsstamps refundablerefundable onon firstfirst orderorder (overseas(overseas free).free). LaboratoryLaboratory MembershipMembership TwoTwo specialspecial offersoffers forfor students:students: LawrenceLawrence (Hatto(Hattonn Garden)Garden) Ltd.,Ltd., 63-6663-66 HattonHatton NewNew TeachlBuyTeach/Buy serviceservice andand freefree Garden,Garden, LondonLondon EC1NEC1N 8L8LEE stonesstones onon anan order.order. M.G.M.G. Welch,Welch, Taunton,Taunton, Somerset.Somerset. TAlTA1 4AJ4AJ A.J.A.J. French,French, FGAFGA AtAt a meetingmeeting ofof thethe Council ofof ManagementManagement 8282 BrookleyBrookley Road,Road, Brockenhurst,Brockenhurst, helheldd atat 2727 GrevilleGreville Street,Street, LondonLondon EClNEC1N 8TN8TN oonn HantsHants S042S042 7RA7RA 2525 NovembeNovemberr 19981998 thethe businessbusiness transactedtransacted Telephone:Telephone: 0159062321401590 623214 includedincluded thethe electionelection ofof thethe following:following:

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R98 .Hatton HOL Garden,T & London CO Eel. N LT8NXD Tel : 0181-9948341 Telephone 0171 -405 0197/5286 Fax: 0181 -723 4266 98 HattoFaxn Garden 0171-430, Londo 1279n EC1 N 8NX Tel: 0181-994 8341 Telephone 0171 -405 0197/5286 Fax:0181-723 4266 Fax 0171-430 1279 Guide to the preparation of typescripts for publication in The Journal of Gemmology

The Editor is glad to consider original articles Illustrations Either transparencies or shedding new light on subjects of gemmological photographs of good quality can be submitted interest for publication in The Journal. Articles for both coloured and black-and-white are not normally accepted which have already illustrations. It is recommended that authors been published elsewhere in English, and an retain copies of all illustrations because of the article is accepted only on the understanding risk of loss or damage either during the printing that (1) full information as to any previous process or in transit. publication (whether in English or another Diagrams must be of a professional quality language) has been given, (2) it is not under and prepared in dense black ink on a good consideration for publication elsewhere and (3) quality surface. Original illustrations will not be it will not be published elsewhere without the returned unless specifically requested. consent of the Editor. All illustrations (maps, diagrams and lYPescripts Two copies of all papers should be pictures) are numbered consecutively with submitted on A4 paper (or USA equivalent) to Arabic numerals and labelled Figure 1, Figure the Editor. Typescripts should be double spaced 2, etc. All illustrations are referred to as with margins of at least 25 mm. They should be 'Figures'. set out in the manner of recent issues of The Tables Must be typed double spaced, using Journal and in conformity with the information few horizontal rules and no vertical rules. They set out below. Papers may be of any length, but are numbered consecutively with Roman long papers of more than 10 000 words (unless numerals (Table IV; etc.). Titles should be capable of division into parts or of exceptional concise, but as independently informative as importance) are unlikely to be acceptable, possible. The approximate position of the Table whereas a short paper of 400-500 words may in the text should be marked in the margin of the achieve early publication. typescript. The abstract, references, notes, captions and Notes and References Authors may choose tables should be typed double spaced on one of two systems: separate sheets. (1) The Harvard system in which authors' On matters of style and rendering, please names (no initials) and dates (and specific consult The Oxford dictionary for writers. and pages, only in the case of quotations) are given editors'(Oxford University Press, 1981). in the main body of the text, e.g. (Giibelin and Koivula, 1986, 29). References are listed Title page The title should be as brief as is alphabetically at the end of the paper under the consistent with clear indication of the content of heading References. the paper. It should be followed by the names (2) The system in which superscript numbers (with initials) of the authors and by their are inserted in the text (e.g .... to which Giibelin addresses. refers.3) and referred to in numerical order at the Abstract A short abstract of 50-100 words is end of the paper under the heading Notes. required. Informational notes must be restricted to the minimum; usually the material can be Key Words Up to six key words indicating the incorporated in the text. If absolutely necessary subject matter of the article should be supplied. both systems may be used. Headings In all headings only the first letter References in both systems should be set out and proper names are capitalized. as follows, with double spacing for ail lines. A This is a first level heading Papers Hurwit, K., 1991. Gem Trade Lab notes. Gems & Gemology, 27, 2,110-11 First level headings are itt bold and are flush left on a separate line. The first text line Books Hughes, RW., 1990. Corundum. following is flush left. Butterworth-Heinemann, London. p. 162 Abbreviations for titles of periodicals are B This is a second level heading those sanctioned by the World List of scientific Second level headings are in italics and are periodicals 4th edn. The place of publication flush left on a separate line. The first text line should always be given when books are following is flush left. referred to. Volume 26 No. 5 January 1999 Contents

The Journal of Gemmology Element mapping of trapiche rubies 289 K. Schmetzer, Zhang Beili, Gao Yan, H-J. Bernhardt and H.A. Hänni

Identification of B jade by FTIR spectrometer with 302 near-IR fibre-optic probe accessory Gao Yan and Zhang Beili

Natrolite from the Bela ophiolite, Pakistan 308 E. Gnos, K. Mahmood, M. Khan, AS. Khan and T. Armbruster

Heat treatment of milky sapphires from the Mogok 313 stone tract, Myanmar U Hla Kyi, P. Buchholz and D. Wolf

Laser-induced luminescence of emeralds from 316 different sources I. Moroz, G. Panczer and M. Roth

Obsidian from Chile with unusual inclusions 321 /. Hyrsl and V. Zdcek

Johachidolite - a new gem 324 R. R. Harding, J.G. Francis, C./.E. Oldershaw and A.H. Rankin

Abstracts 330

Book Reviews 334

Cover Picture Proceedings of the Gemmological Association and 340 Johachidolite in a rock Gem Testing Laboratory of Great Britain and specimen from the Notices original locality in Korea Copyright © 1999 shown next to a cut stone of 14.02 ct recently The Gemmological Association and acquired in Myanmar Gem Testing Laboratory of Great Britain (see 'Johachidolite - a Registered Office: Palladium House, 1-4 Argyll Street, London W1V 2LD new gem', pp. 324-9)

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