GemmologyThe Journal of 2015 / Volume 34 / No. 5 The Gemmological Association of Great Britain Get closer to the source 13–20 June 2015 Gem-A is hosting the trip of a lifetime to Idar-Oberstein: the home of gem carving. Visits include Edelsteinminen Steinkaulenberg, Kupferbergwerk in Fischbach, DGemG, Schneider gem tools, Deutsches Mineralienmuseum, Historische Weiherschleife and lapidaries, as well as the opportunity to sample the very best of small-town culture. Prices start at just £1,545, and include travel, accommodation, visits, breakfast and dinner. For more information or to secure your place, contact [email protected]. Join us. The Gemmological Association of Great Britain, 21 Ely Place, London, EC1N 6TD, UK. T: +44 (0) 20 7404 3334 F: +44 (0) 20 7404 8843. Registered charity no. 1109555. A company limited by guarantee and registered in England No. 1945780. Registered Office: 3rd Floor, 1-4 Argyll Street, London W1F 7LD. Idar-Oberstein_A4_04-2015.indd 1 4/11/2015 9:35:05 PM GemmologyThe Journal of 2015 / Volume 34 / No. 5 COLUMNS p. 395 381 What’s New GL Gem Spectrometer| p. 387 Photography accessory clips| Presidium Gem Indicator| Newsletters from the Gem Testing Laboratory, GGTL and ICGL|GIT Lab updates| Gold demand trends|Handbook of Gemmology, 3rd edn.|Oiled gems lab alert|Pink and blue CVD synthetic diamonds|World Diamond Magazine|Coloured stone app 384 Practical Gemmology ARTICLES Colour grading of synthetic Feature Article moissanite 404 The Potential of a Portable EDXRF Spectrometer 386 Gem Notes for Gemmology Large kunzite from Brazil| By Franz A. Herzog Marble-hosted ruby mine, Mogok, Myanmar|Secondary Gemmological Briefs gem deposit in Mogok, Myanmar|Pink play-of-colour 420 Green Lead-Glass-Filled Sapphires opal from Idaho|Dumortierite By Thanong Leelawatanasuk, Namrawee Susawee, Supparat inclusions in quartz from Promwongnan and Nicharee Atsawatanapirom Brazil|Quartz sphere with large inclusion|Zawadi 428 Demantoid from Balochistan, Pakistan: sapphires|Tourmaline from Gemmological and Mineralogical Characterization the Havey quarry, Maine, USA| By Ilaria Adamo, Rosangela Bocchio, Valeria Diella, Franca Greenland tugtupite|Orange Caucia and Karl Schmetzer zircon from Myanmar|Glass imitation of emerald|Large black 434 Nail-head Spicules as Inclusions in Chrysoberyl from synthetic moissanite as a black Myanmar diamond imitation|Peridot- By Karl Schmetzer and Michael S. Krzemnicki polymer composite|Dyed quartzite imitating bicoloured 441 Letters tourmaline 444 Conferences Cover Photo: AGA Tucson|GILC Tucson|GIT 2014 The attractive appear- ance of this 54.10 ct Zawadi sapphire is 448 Gem-A Notices created by its ‘golden’ sheen and contrasting 453 Learning Opportunities network of dark fractures and twin planes. Courtesy of 457 New Media Primagem; photo by Jeff Scovil. 463 Literature of Interest The Journal is published by Gem-A in collaboration with SSEF and with the support of AGL and GIT. ISSN: 1355-4565, http://dx.doi.org/10.15506/JoG.2015.34.5 i The Journal of emmology G THE GEMMOLOGICAL ASSOCIATION OF GREAT BRITAIN Editor-in-Chief Production Editor Marketing Consultant Brendan M. Laurs Mary A. Burland Ya’akov Almor [email protected] [email protected] [email protected] 21 Ely Place London EC1N 6TD Executive Editor Editor Emeritus Assistant Editor UK James H. Riley Roger R. Harding Michael J. O’Donoghue t: +44 (0)20 7404 3334 Associate Editors f: +44 (0)20 7404 8843 Edward Boehm, RareSource, Chattanooga, Tennessee, USA; Alan T. Collins, King’s College e: [email protected] London; John L. Emmett, Crystal Chemistry, Brush Prairie, Washington, USA; Emmanuel w: www.gem-a.com Fritsch, University of Nantes, France; Rui Galopim de Carvalho, Portugal Gemas, Lisbon, Registered Charity No. 1109555 Portugal; Lee A. Groat, University of British Columbia, Vancouver, Canada; Thomas Registered office: Palladium House, Hainschwang, GGTL Gemlab–Gemtechlab Laboratory, Balzers, Liechtenstein; Henry A. 1–4 Argyll Street, London W1F 7LD Hänni, GemExpert, Basel, Switzerland; Jeff W. Harris, University of Glasgow; Alan D. Hart, The Natural History Museum, London; Ulrich Henn, German Gemmological Association, Idar-Oberstein; Jaroslav Hyršl, Prague, Czech Republic; Brian Jackson, National Museums Scotland, Edinburgh; Stefanos Karampelas, Gübelin Gem Lab Ltd., Lucerne, Switzerland; Lore Kiefert, Gübelin Gem Lab Ltd., Lucerne, Switzerland; Hiroshi Kitawaki, Central Gem Laboratory, Tokyo, Japan; Michael S. Krzemnicki, Swiss Gemmological Institute SSEF, President Basel; Shane F. McClure, Gemological Institute of America, Carlsbad, California; Jack Harry Levy M. Ogden, Striptwist Ltd., London; Federico Pezzotta, Natural History Museum of Milan, Vice Presidents Italy; Jeffrey E. Post, Smithsonian Institution, Washington DC, USA; Andrew H. Rankin, David J. Callaghan, Alan T. Collins, Kingston University, Surrey; George R. Rossman, California Institute of Technology, Noel W. Deeks, E. Alan Jobbins, Pasadena, USA; Karl Schmetzer, Petershausen, Germany; Dietmar Schwarz, AIGS Lab Co. Michael J. O’Donoghue, Ltd., Bangkok, Thailand; Menahem Sevdermish, GemeWizard Ltd., Ramat Gan, Israel; Andrew H. Rankin Guanghai Shi, China University of Geosciences, Beijing; James E. Shigley, Gemological Institute of America, Carlsbad, California; Christopher P. Smith, American Gemological Honorary Fellows Laboratories Inc., New York; Evelyne Stern, London; Elisabeth Strack, Gemmologisches Gaetano Cavalieri, Terrence S. Institut, Hamburg, Germany; Tay Thye Sun, Far East Gemological Laboratory, Singapore; Coldham, Emmanuel Fritsch Pornsawat Wathanakul, Gem and Jewelry Institute of Thailand, Bangkok; Chris M. Welbourn, Reading, Berkshire; Joanna Whalley, Victoria and Albert Museum, London; Honorary Diamond Member Bert Willems, Leica Microsystems, Wetzlar, Germany; Bear Williams, Stone Group Martin Rapaport Laboratories LLC, Jefferson City, Missouri, USA; J.C. (Hanco) Zwaan, National Museum of Natural History ‘Naturalis’, Leiden, The Netherlands. Honorary Life Members Anthony J. Allnutt, Hermann Bank, Content Submission Mary A. Burland, Terence M.J. The Editor-in-Chief is glad to consider original articles, news items, conference/excursion Davidson, Peter R. Dwyer-Hickey, reports, announcements and calendar entries on subjects of gemmological interest for Gwyn M. Green, Roger R. Harding, publication in The Journal of Gemmology. A guide to the preparation of manuscripts John S. Harris, J. Alan W. Hodgkinson, is given at www.gem-a.com/publications/journal-of-gemmology.aspx, or contact the John I. Koivula, Jack M. Ogden, Production Editor. C.M. (Mimi) Ou Yang, Evelyne Stern, Ian Thomson, Vivian P. Watson, Subscriptions Colin H. Winter Gem-A members receive The Journal as part of their membership package, full details of which are given at www.gem-a.com/membership.aspx. Laboratories, libraries, museums Chief Executive Officer and similar institutions may become Direct Subscribers to The Journal (see www.gem-a. James H. Riley com/publications/subscribe.aspx). Council Advertising Jason F. Williams – Chairman Enquiries about advertising in The Journal should be directed to the Marketing Consultant. Mary A. Burland, Jessica M. Cadzow, Steven J.C. Collins, Paul F. Greer, For more information, see www.gem-a.com/publications/journal-of-gemmology/advertising- Alan D. Hart, Nigel B. Israel, Jonathan in-the-journal.aspx. Lambert, Richard M. Slater, Miranda Copyright and Reprint Permission E.J. Wells, Stephen Whittaker Abstracting with credit to the source, photocopying isolated articles for noncommercial classroom use, and photocopying by libraries for private use of patrons, are permitted. Branch Chairmen Midlands – Georgina E. Kettle Requests to use images published in The Journal should be directed to the Editor-in- North East – Mark W. Houghton Chief. Give the complete reference citation and the page number for the image(s) in South East – Veronica Wetten question, and please state how and where the image would be used. South West – Richard M. Slater The Journal of Gemmology is published quarterly by Gem-A, The Gemmological Association of Great Britain. Any opinions expressed in The Journal are understood to be the views of the contributors and not necessarily of the publisher. Printed by DG3 (Europe) Ltd. ™ © 2015 The Gemmological Association of Great Britain Understanding Gems Cert no. TT-COC-002454 ISSN: 1355-4565 ii The Journal of Gemmology, 34(5), 2015 What’s New What’s New INSTRUMENTS AND TECHNIQUES GL Gem Spectrometer NIR PL405 etc., and are available in two sizes: The GL Gem Spectrometer NIR PL405 is a dual five joints (15.6 cm long) or 10 purpose spectrometer for photoluminescence and joints (23.6 cm long). Visit www. Vis-NIR spectroscopy (550–1000 nm) that was re- lithographie.org/bookshop/five_ leased by Gemlab Group in December 2014. The joint_black_flexible.htm. spectrometer has a higher resolution but shorter wavelength range than Gemlab’s previous GL Gem Spectrometer (300–1000 Presidium Gem Indicator nm). It is equipped with a The Presidium Gem Indicator was launched at the long-wave pass filter and Hong Kong International Jewellery Show in March is optimized for the NIR 2015. The instrument is an enhanced and more range. The unit is simply convenient handheld version of the Presidium Gem plugged into a computer’s Tester/Colored Stone Estimator. It distinguishes be- USB port; no additional tween diamonds and various other gems using ther- drivers are necessary. It mal conductivity, and it comes can be used to identify vari- with a changeable