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Volume 35 / No. 2 / 2016 GemmologyThe Journal of Volume 35 / No. 2 / 2016 The Gemmological Association of Great Britain SPECIAL STUDENT RATE FOR 2016 Gem-A Conference 5–6 November 2016 The Gem-A Conference will be held at the prestigious Royal Institute of British Architects (RIBA) in Marylebone, London. This year will feature talks from the following renowned gem experts: • Jim Clanin, mining engineer • Helen Molesworth, Gübelin Academy • Pat Daly, valuer and Gem-A Tutor • Danny Sanchez, photomicrographer • David Fisher, De Beers • Robert Weldon, GIA • Ian Harebottle, Gemfields • Dr Michael Wise, Smithsonian • Bill Larson, Palagems.com Institution To keep up to date with the latest from the Conference and for information on how to book please visit the Gem-A website. 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. Conference_A4_06-2016.indd 1 27/06/2016 09:58:19 Contents GemmologyThe Journal of Volume 35 / No. 2 / 2016 COLUMNS p. 168 91 What’s New ASDI device|D-Secure|Dialite MasterGrader|GemLab in- strument updates|De Beers’ diamond jewellery demand p. 103 and outlook|GIT lab updates and Trade Review|IAA and ICGL newsletters|IGDA news and ‘Overview of the Lab-Grown Diamond Industry’|JGGL Gem Inform- ation|Kyawthuite|Margarit- ARTICLES ologia newsletter|PDAC diamond abstracts|Photomicro- Feature Articles graphy of amber|Precious 120 Major- and Trace-element Composition of Paraíba-type Stones Multi-Stakeholder Tourmaline from Brazil, Mozambique and Nigeria Working Group report|Santa Fe Symposium proceedings|AIGS By Martin Okrusch, Andreas Ertl, Ulrich Schüssler, Ekkehart gem dictionary app|Corporate Tillmanns, Helene Brätz and Hermann Bank social responsibility course 140 Identification of Colourless HPHT-grown Synthetic 96 Gem Notes Diamonds from Shandong, China Axinite from Pakistan|Cat’s-eye By Zhonghua Song, Taijin Lu, Shi Tang, Jie Ke, Jun Su, Bo Gao, diaspore from Turkey|Polymer- filled star enstatite from Ning Hu, Jun Zhang, Jun Zhou, Lijun Bi and Dufu Wang Norway|Garnet mining in Tanzania|Kyanite from 148 Gem-quality Sekaninaite from the Czech Republic Pakistan|Black star sapphires By Radek Hanus, Ivana Kusá and Jana Kasíková from Liberia|Age of Myan- mar sapphires|Pink spinel Gemmological Brief from Mozambique|Tantalite- (Mn) from Afghanistan|Coral 156 Phase Transformation of Epigenetic Iron Staining: Indication branch ‘pearl’ from a giant of Low-Temperature Heat Treatment in Mozambique Ruby clam|Quartz beads imitating By Tasnara Sripoonjan, Bhuwadol Wanthanachaisaeng and tourmalinated quartz Thanong Leelawatanasuk 162 Letters 164 Conferences Accredited Gemologists Association Las Vegas|China Gems & Jewelry Cover Photo: Academic Exchange|Mediterranean Gemmological & Jewellery Con- These Cu-bearing tour- ference|Scottish Gemmological Association|Swiss Gemmological Society malines are from Mozam- bique (13.93 ct cushion and ~5 ct stone in ring) 170 Gem-A Notices and from Paraíba, Brazil (3.5 mm gems in bracelet and 4.02 ct oval). Courtesy 171 Learning Opportunities of Collectorfinejewelry. com, Palagems.com (13.93 ct stone) and Leslie Hind- 174 New Media man Auctioneers, Chicago, Illinois, USA (4.02 ct gem); photo by Orasa Weldon. 176 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.2016.35.2 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 Editorial Assistant Editor Emeritus Executive Editor London EC1N 6TD Carol M. Stockton Roger R. Harding Alan D. Hart UK Associate Editors t: +44 (0)20 7404 3334 Edward Boehm, RareSource, Chattanooga, Tennessee, USA; Alan T. Collins, King’s College f: +44 (0)20 7404 8843 London; John L. Emmett, Crystal Chemistry, Brush Prairie, Washington, USA; Emmanuel e: [email protected] Fritsch, University of Nantes, France; Rui Galopim de Carvalho, Portugal Gemas, Lisbon, w: www.gem-a.com Portugal; Lee A. Groat, University of British Columbia, Vancouver, Canada; Thomas Hainschwang, GGTL Laboratories, Balzers, Liechtenstein; Henry A. Hänni, GemExpert, Registered Charity No. 1109555 Basel, Switzerland; Jeff W. Harris, University of Glasgow; Alan D. Hart, The Natural History Registered office: Palladium House, Museum, London; Ulrich Henn, German Gemmological Association, Idar-Oberstein; Jaroslav 1–4 Argyll Street, London W1F 7LD Hyršl, Prague, Czech Republic; Brian Jackson, National Museums Scotland, Edinburgh; Stefanos Karampelas, GRS Gemresearch Swisslab, Lucerne, Switzerland; Lore Kiefert, Gübelin Gem Lab Ltd., Lucerne, Switzerland; Hiroshi Kitawaki, Central Gem Laboratory, Tokyo, Japan; Michael S. Krzemnicki, Swiss Gemmological Institute SSEF, Basel; Shane F. McClure, Gemological Institute of America, Carlsbad, California; Jack M. Ogden, Striptwist President Ltd., London; Federico Pezzotta, Natural History Museum of Milan, Italy; Jeffrey E. Post, Harry Levy Smithsonian Institution, Washington DC, USA; Andrew H. Rankin, Kingston University, Surrey; George R. Rossman, California Institute of Technology, Pasadena, USA; Karl Vice Presidents Schmetzer, Petershausen, Germany; Dietmar Schwarz, AIGS Lab Co. Ltd., Bangkok, Thailand; David J. Callaghan, Alan T. Collins, Menahem Sevdermish, GemeWizard Ltd., Ramat Gan, Israel; Guanghai Shi, China University Noel W. Deeks, E. Alan Jobbins, of Geosciences, Beijing; James E. Shigley, Gemological Institute of America, Carlsbad, Andrew H. Rankin California; Christopher P. Smith, American Gemological Laboratories Inc., New York, New York; Evelyne Stern, London; Elisabeth Strack, Gemmologisches Institut Hamburg, Germany; Honorary Fellows Tay Thye Sun, Far East Gemological Laboratory, Singapore; Pornsawat Wathanakul, Gem Gaetano Cavalieri, Terrence and Jewelry Institute of Thailand, Bangkok; Chris M. Welbourn, Reading, Berkshire; Joanna S. Coldham, Emmanuel Fritsch Whalley, Victoria and Albert Museum, London; Bert Willems, Leica Microsystems, Wetzlar, Germany; Bear Williams, Stone Group Laboratories LLC, Jefferson City, Missouri, USA; J.C. Honorary Diamond Member (Hanco) Zwaan, National Museum of Natural History ‘Naturalis’, Leiden, The Netherlands. Martin Rapaport Content Submission Honorary Life Members The Editor-in-Chief is glad to consider original articles, news items, conference/excursion Anthony J. Allnutt, Hermann Bank, reports, announcements and calendar entries on subjects of gemmological interest for Mary A. Burland, Terence M.J. Davidson, publication in The Journal of Gemmology. A guide to the various sections and the preparation Peter R. Dwyer-Hickey, Gwyn M. Green, of manuscripts is given at www.gem-a.com/publications/journal-of-gemmology/submit- Roger R. Harding, John S. Harris, an-article.aspx, or contact the Production Editor. J. Alan W. Hodgkinson, John I. Koivula, Subscriptions Jack M. Ogden, C.M. (Mimi) Ou Yang, Gem-A members receive The Journal as part of their membership package, full details of Evelyne Stern, Ian Thomson, Vivian P. which are given at www.gem-a.com/membership.aspx. Laboratories, libraries, museums and Watson, Colin H. Winter similar institutions may become Direct Subscribers to The Journal (see www.gem-a.com/ publications/subscribe.aspx). Chief Executive Officer Alan D. Hart Advertising Enquiries about advertising in The Journal should be directed to the Marketing Consultant. Council For more information, see www.gem-a.com/publications/journal-of-gemmology/advertising- Miranda E.J. Wells – Chair in-the-journal.aspx. Kathryn L. Bonanno, Mary A. Burland, Justine L. Carmody, Paul F. Greer, Kerry Database Coverage H. Gregory, J. Alan W. Hodgkinson, The Journal of Gemmology is covered by the following abstracting and indexing services: Nigel B. Israel, Jack M. Ogden, Richard Australian Research Council academic journal list, British Library Document M. Slater, Christopher P. Smith Supply Service, Chemical Abstracts (CA Plus), Copyright Clearance Center’s RightFind application, CrossRef, EBSCO (Academic Search International, Branch Chairmen Discovery Service and TOC Premier), Gale/Cengage Learning Academic Midlands – Georgina E. Kettle OneFile, GeoRef, Mineralogical Abstracts, ProQuest, Scopus and the Thomson North East – Mark W. Houghton Reuters’ Emerging Sources Citation Index (in the Web of Science). South East – Veronica Wetten South West – Richard M. Slater Copyright and Reprint Permission Full details of copyright and reprint permission are given on The Journal’s website. 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. ™ © 2016 The Gemmological Association of Great Britain Understanding Gems ISSN: 1355-4565 Cert no. TT-COC-002454 ii The Journal of Gemmology, 35(2), 2016 What’s New INSTRUMENTS AND TECHNIQUES ASDI Device Updated incandescent), diffuse In 2015, SSEF twice updated its own Automated illumination for photo- Spectral Diamond Inspection (ASDI) device, graphy and a neutral grey and these changes background. The unit will be included on measures 34
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