Volume 21 / No. 3 / 1988
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Volume 21 No.3 July 1988 TheJournal of Gemmology GEMMOLOGICAL ASSOCIATION OF GREAT BRITAIN OFFICERS AND COUNCIL President: *Sir Frank Claringbull, Ph.D., F.Inst.P, FGS Vice-President: R. K. Mitchell, FGA Chairman: *D. J. Callaghan, FGA Vice-Chairman: *N. W Deeks, FGA Honorary Treasurer: *N. B. Israel, FGA Members elected to Council: *A.J.AUnutt,M.Sc, J. W Harris, B.Sc., *J.B. Nelson, Ph.D., Ph.D.,FGA M.Sc.,Ph.D. FRMS, EInst.P, FGA *E. M. Bruton, FGA J. A. W Hodgkinson, FGA W Nowak, CEng., *C. R. Cavey, FGA D. Inkersole, FGA F.R.Ae.S.,FGA EJ.E.Daly,B.Sc, B. Jackson, FGA M. J. O'Donoghue, FGA *E. A. Jobbins, B.Sc, C.Eng., MA, FGS, FGA *A. E. Farn, FGA FIMM, FGA *P G. Read, C.Eng., A. J. French, FGA *G. H.Jones, B.Sc, Ph.D., MIEE, MIERE, FGA G. Green, FGA FGA *K. Scarratt, FGA *R.R. Harding, B.Sc., D. G. Kent, FGA E. Stern, FGA D. Phil, FGA D. M. Larcher, FGA *C. H. Winter, FGA A. D. Morgan, FIBF, FGA ^Members of the Executive Committee Branch Chairmen: Midlands Branch: J. Leek, FGA North-West Branch: R. Perrett, FGA South Yorkshire & District Branch: G. A. Massie, FGA Examiners: A. J. Allnutt, M.Sc, Ph.D., FGA D. G. Kent, FGA E. M. Bruton, FGA P Sadler, B.Sc, FGS, FGA A. E. Farn, FGA K. Scarratt, FGA R. R. Harding, B.Sc, D.Phil., FGA M. Virkkunen, M.Phil., FGA E. A. Jobbins, B.Sc, C.Eng., FIMM, FGA C. Woodward, B.Sc, FGA G. H. Jones, B.Sc, Ph.D., FGA Editor: E. A. Jobbins, B.Sc, C.Eng., FIMM, FGA Editorial Assistant: Mary A. Burland Curator: C. R. Cavey, FGA Secretary: Jonathan P. Brown, FGA, Barrister Saint Dunstan's House, Carey Lane, London EC2V 8AB (By Goldsmith's Hall) Telephone: 01-726 4374 The Journal of Gemmology VOLUME 21 NUMBER THREE JULY 1988 Cover Picture Boat-shaped etch figures on a first order prism face of a green beryl crystal from the Soviet Union. The c-axis runs in the long direction. Nomarski Differential Interference Contrast. 80x. (See 'Etch figures on beryl', p. 142) Photograph by John I. Koivula. ISSN: 0022-1252 130 J. Gemm., 1988, 21, 3 Douglas Wheeler It is with deep regret that we report the death on Saturday 7 May 1988 of Douglas Wheeler, former Assistant Secretary of the Gemmological Associa tion of Great Britain and Deputy Secretary of the National Association of Goldsmiths. Douglas was born on 15 May 1922 in East Ham, London, and joined the staff of the G A and NAG in 1936 at the age of 14. He served both associations continuously except for a period of five years in HM Forces. On his 19th birthday he volunteered for the RAF and after flying training in Canada saw active service in Europe. He was commissioned at 21. Douglas returned to civilian life in 1946 and rejoined the Associations, working alongside the late Gordon Andrews and his brother, the late Harry Wheeler, both of whom had also returned from the services. He studied at Chelsea Polytechnic as an evening class student and became an FGA in 1948. He was appointed Assistant Secretary for the G A in 1973 and Deputy Secretary of the NAG in 1976. Douglas retired from business in November 1983. He said at that time that he had greatly enjoyed his years with the two Associations and had been lucky in the people he had met and worked with. He looked forward to a new life of retirement in Norfolk. He leaves his wife, Kathleen, two sons, Michael and Stephen and grandchildren. © Copyright the Gemmological Association ISSN: 0022-1252 J.J. Gemm.,Gemm., \988,21,31988,21,3 131131 NotesNotes fromfrom thethe LaboratoryLaboratory - 1U2 Kenneth Scarratt, FGAFGA TheThe GemGem TestingTesting LaboratoryLaboratory ofof GreatGreat Britain,Britain, 2727 GrevilleGreville Street,Street, London,London, ECINEC1N 8SU8SU TheThe LennixLennix syntheticsynthetic emerald.emerald, 3nan updateupdate determinedetermine thethe SGsSGs ooff thesethese crystalscrystals a liquiliquidd waswas FamFarn firstfirst describeddescribed ththee LenniLennixx syntheticsynthetic emeremer mixedmixed inin whichwhich aann inclusioinclusionn frefreee anandd colourlesscolourless aldald inin 19801980 (Fam,(Farn, 1980)1980) followinfollowingg a giftgift in*197in 19799 ofof a quartzquartz waswas suspendedsuspended atat roomroom temperature.. WhenWhen numbenumberr ofof samplesample crystalscrystals toto ththee Laboratory.Laboratory. LittleLittle thethe LenniLennixx crystalscrystals werewere placeplacedd intointo ththee samesame liquidliquid hashas beebeenn seenseen ofof thithiss syntheticsynthetic inin ththee markemarkett sincesince withwith ththee quartzquartz 'marker''marker' eaceachh behavedbehaved inin thethe samesame Farn'Farn'ss firsfirstt reportreport,, however,however, lastlast yearyear a furtherfurther giftgift ooff wawayy aass thethe quartz,quartz, ie.i.e. atat roomroom temperaturetemperature theythey threethree crystalscrystals waswas madmadee toto thethe LaboratoryLaboratory byby werweree suspendedsuspended iinn ththee samesame position,position, asas ththee tempertemper SzemesSzemes AttHaAttila ofof Enterprise Fran~aiseFrançaise de de Fabrication Fabrication atureature waswas graduallgraduallyy raisedraised thetheyy slowlyslowly sanksank atat thethe D'emeraude de CullureCulture (Figure(Figure 1)1) andand anotheranother samesame ratratee asas andand withwith thethe quartzquartz markermarker,, anandd asas thethe descriptiondescription (Graziani,(Graziani, elet al., 1987)1987) waswas publishedpublished inin temperaturetemperature waswas loweredlowered theythey slowlyslowly floatedfloated toto thethe GemsGemsàf & Gemology.GemDlogy. surfacesurface atat thethe samesame ratratee andand withwith ththee quartzquartz marker.marker. Fig.. 11.. LenniLennixx synthetisyntheticc emeralemeraldd crystals.. FigFig.. 22.. CrystaCrystall aggregateaggregatess anandd needle-likneedle-likee inclusioninclusionss iinn ththee LenniLcn nixx synthetisyntheticc emeraldemerald.. ThThee threthreee crystalcrystalss recentlrecentlyy donatedonatedd weigweighh 0.810.81,, ThiThiss indicateindicatess aann SSGG ooff 2.62.655 (somewha(somewhatt belobeloww ththee 0.710.71,, anandd 0.80.822 ctct,, ththee 0.80.811 cctstonet stone measurinmeasuringg 4.34-4.34- valuvaluee thathatt iiss normallnormallyy expecteexpectedd ooff a naturalnatural emerald)emerald) 5.65.666 x 2.82.844 mmmm.. AlAlll fluoresce reredd whewhenn irradiatedirradiated whicwhichh iiss alsalsoo consistenconsistentt witwithh ththee findingfindingss ooff bothboth witwithh eitheeitherr long-wavlong-wavee oorr short-wavshort-wavee ultravioleultraviolett rayrayss FarFaron (2.65(2.65)) anandd GrazianiGraziani,, et af.al. (2.65-2.66).(2.65-2.66). anandd alsalsoo X-rayX-rayss (diffractio(diffractionn tubetube,, MMoo targetargett aatt 4400 kkVV ThThee inclusioninclusionss anandd growtgrowthh featurefeaturess araree similasimilarr ttoo anandd 1155 mA)rnA).. FollowinFollowingg ththee slicinslicingg anandd polishinpolishingg ooff thosthosee ooff ththee originaoriginall 19719799 samplessamples,, iinn thathatt ththee ththee 0.80.811 cClt specimespecimenn refractivrefractivee indeindexx measurementsmeasurements LenniLennixx synthetisyntheticc emeralemeraldd iiss botbothh heavilheavilyy includeincludedd ooff 1.561-1.561.561-1.5655 werweree madmadee anandd thesthesee araree botbothh anandd zonedzoned.. AAss ononee hahass comcomee ttoo expecexpectt a synthetisyntheticc consistenconsistentt witwithh flufluxx growgrownn synthetisyntheticc emeraldemeraldss iinn emeralemeraldd ttoo bbee ooff a highighh qualitqualityy (a(att leasleastt iinn termteooss ooff generagenerall anandd similasimilarr ttoo thosthosee reportereportedd bbyy FarFaron clarityclarity)) ththee facetefacetedd LenniLennixx synthetisyntheticc emeralemeraldd poseposess (1.562-1.566(1.562-1. 566)) anandd GrazianiGraziani,, etal.er al. (1.559-1.562)(1.559-1. 562).. a threathreatt ttoo ththee over-confidentover-confident.. WheWhenn examineexaminedd iinn IIt t iiss ofteoftenn difficuldifficultt ttoo obtaiobtainn accurataccuratee resultresultss whewhenn ththee directiodirectionn alonalongg ththee c axiaxiss (Figur(Figuree 22)) a multitudmultitudee determinindetenniningg ththee SGSGss ooff stonestoness iinn ththee sizsizee rangrangee ooff ooff smal smalll crystacrystall aggregateaggregatess araree seeseenn whicwhichh araree similasimilarr thesthesee crystalcrystalss iiff ththee hydrostatihydrostaticc methomethodd iiss usedused.. TToo ttoo thosthosee describedescribedd bbyy FarFamn (Farn(Farn,, 19801980.. FigureFiguress 55 © CopyrighCopyrightt ththee GemmologicaGemmologicall AssociationAssociation ISSN:: 0022-12S20022-1252 132132 J.J . Gemm.,Gemm., 1988,21,31988,21,3 FACE B Fig.Fig. 4.4. LineLine dr-dwingdrawing sshowinhowingg thethe directiondirection inin whichwhich thethe O.!l10.81 c[ct LennixLennix 'yotsyntheti heticc erneemeral raidd was sawnsawn (A(A) •an mld popolished Ii,hed. FigFig.. 33.. CrystaCry,[all aggregateaggregatess anantid zoninzoningg iinn ththee LenniLennixx synthetisynTheticc Fig.. 55.. ZoninZon ing g iinn ththee LenniLcnnixx synthetisy n t heticc emeralderne raid., emerald.. rigFig. 66. 'Tw'Twoo phase'inclusion phase' inclusionss i inn ththee LenniLennixx syntheti synihe(icc emeraldemerald.. FigFig.. 77.. 'Tw'Twoo phasepha,e'' anandd otheotherr needle-likneedle·likee inclusioninclusionss iinn ththee LenniLennixx synthetisyntheticc emeraldemerald. J. Gernm., 1988,21,3 133 and 6) and a clearly visible zoned structure can be The filling of cavities and feathers in ruby observed within a limited area close to the edge of Rubies in which cavities have been filled with the crystal. This zoning running 'parallel' with the glass are no longer an uncommon sight in the outer shape of the crystal can be