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Volume 34 / No. 8 / 2015 GemmologyThe Journal of 2015 / Volume 34 / No. 8 The Gemmological Association of Great Britain Flexible study to suit you Our Online Distance Learning (ODL) programmes offer you the chance to study our world-famous Gemmology and Diamond Diplomas from home, work or anywhere else you choose. Graduates of our Gemmology and Diamond Diplomas may apply for Membership, entitling them to use the prestigious FGA and DGA status respectively — recognized symbols of excellence in the trade. To sign up contact [email protected]. Gemmology Foundation Gemmology Diploma Diamond Diploma (nine month course) (nine month course) (nine month course) Starts: 7 March 2016 Starts: 14 March 2016 Starts: 14 March 2016 Price: £2,160 Price: £3,150 Price: £2,625 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. Contents GemmologyThe Journal of 2015 / Volume 34 / No. 8 647 Editorial p. 719 COLUMNS 648 What’s New Gemlogis Taupe Diamond Segregator|M-Screen melee screening device|Presidium Synthetic Diamond Screener| p. 675 Spekwin32 software|CIBJO coral book|Global diamond industry 2015|Flux-grown synthetic spinel|ICGL Newsletter| ISO standards for diamonds| The Journal’s cumulative index|Rare books scanned by GIA|Responsible practices and jewellery consumption|RJC 2015 progress report 652 Practical Gemmology ARTICLES The Kerez effect in green tourmaline 678 From Exsolution to ‘Gold Sheen’: A New Variety of 654 Gem Notes Corundum Apatite from Mozambique| By Thanh Nhan Bui, Katerina Deliousi, Tanzim Khan Malik and Chondrodite from Tanzania| Katrien De Corte Purple garnets from East Africa|Green prase opal 692 Age Determination of Zircon Inclusions in Faceted from Tanzania|Trapiche ruby from Myanmar|Sapphires Sapphires from Kenya|Shattuckite and By Klemens Link bisbeeite from the DRC| Purple tourmaline from 702 Identification of a CVD Synthetic Diamond with a Mozambique|Tourmaline ‘Tree Ring’ Growth Pattern slices from Myanmar|Wurtzite By Yan Lan, Rong Liang, Taijin Lu, Yong Zhu, Tianyang Zhang, from Tanzania|Star zircon| Xuan Wang, Jian Zhang, Hong Ma and Zhonghua Song Amber processing in Lithu- ania|Shungite|Gem-set cultured pearls 712 Conferences Canadian Gemmological Association|First World Emerald Symposium|Gem-A|Geological Society of America Cover Photo: This 5.86 ct intense 721 Gem-A Notices reddish purple garnet was cut by Jeff White from rough material 735 Learning Opportunities that was mined in Mozambique; see Gem Note on pp. 656–658. 738 New Media Photo by Jeff White. 743 Literature of Interest 746 Volume Index The Journal is published by Gem-A in collaboration with SSEF and with the support of AGL. ISSN: 1355-4565, http://dx.doi.org/10.15506/JoG.2015.34.8 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 Editor Emeritus Assistant Editor London EC1N 6TD Roger R. Harding Michael J. O’Donoghue 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, Basel, Registered Charity No. 1109555 Switzerland; Jeff W. Harris, University of Glasgow; Alan D. Hart, The Natural History Museum, Registered office: Palladium House, London; Ulrich Henn, German Gemmological Association, Idar-Oberstein; Jaroslav Hyršl, 1–4 Argyll Street, London W1F 7LD Prague, Czech Republic; Brian Jackson, National Museums Scotland, Edinburgh; Stefanos Karampelas, Basel, 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 Ltd., London; Federico Pezzotta, Natural President History Museum of Milan, Italy; Jeffrey E. Post, Smithsonian Institution, Washington DC, Harry Levy USA; Andrew H. Rankin, Kingston University, Surrey; George R. Rossman, California Institute of Technology, Pasadena, USA; Karl Schmetzer, Petershausen, Germany; Dietmar Vice Presidents Schwarz, AIGS Lab Co. Ltd., Bangkok, Thailand; Menahem Sevdermish, GemeWizard Ltd., David J. Callaghan, Alan T. Collins, Ramat Gan, Israel; Guanghai Shi, China University of Geosciences, Beijing; James E. Shigley, Noel W. Deeks, E. Alan Jobbins, Gemological Institute of America, Carlsbad, California; Christopher P. Smith, American Michael J. O’Donoghue, Gemological Laboratories Inc., New York, New York; Evelyne Stern, London; Elisabeth Andrew H. Rankin Strack, Gemmologisches Institut Hamburg, Germany; Tay Thye Sun, Far East Gemological Laboratory, Singapore; Pornsawat Wathanakul, Gem and Jewelry Institute of Thailand, Honorary Fellows Bangkok; Chris M. Welbourn, Reading, Berkshire; Joanna Whalley, Victoria and Albert Gaetano Cavalieri, Terrence Museum, London; Bert Willems, Leica Microsystems, Wetzlar, Germany; Bear Williams, Stone S. Coldham, Emmanuel Fritsch Group Laboratories LLC, Jefferson City, Missouri, USA; J.C. (Hanco) Zwaan, National Museum of Natural History ‘Naturalis’, Leiden, The Netherlands. Honorary Diamond Member Martin Rapaport Content Submission The Editor-in-Chief is glad to consider original articles, news items, conference/excursion Honorary Life Members reports, announcements and calendar entries on subjects of gemmological interest for Anthony J. Allnutt, Hermann Bank, publication in The Journal of Gemmology. A guide to the various sections and the preparation Mary A. Burland, Terence M.J. Davidson, of manuscripts is given at www.gem-a.com/publications/journal-of-gemmology.aspx, or Peter R. Dwyer-Hickey, Gwyn M. Green, contact the Production Editor. Roger R. Harding, John S. Harris, Subscriptions J. Alan W. Hodgkinson, John I. Koivula, Gem-A members receive The Journal as part of their membership package, full details of Jack M. Ogden, C.M. (Mimi) Ou Yang, which are given at www.gem-a.com/membership.aspx. Laboratories, libraries, museums and Evelyne Stern, Ian Thomson, Vivian P. similar institutions may become Direct Subscribers to The Journal (see www.gem-a.com/ Watson, Colin H. Winter publications/subscribe.aspx). Interim Chief Executive Officer Advertising Nicholas H. Jones Enquiries about advertising in The Journal should be directed to the Marketing Consultant. For more information, see www.gem-a.com/publications/journal-of-gemmology/advertising- Council in-the-journal.aspx. Nigel B. Israel – Chairman Kathryn L. Bonanno, Mary A. Burland, Database Coverage Justine L. Carmody, Paul F. Greer, Kerry The Journal of Gemmology is covered by the following abstracting and indexing services: H. Gregory, Alan D. Hart, Australian Research Council academic journal list, British Library Document J. Alan W. Hodgkinson, Jack M. Ogden, Supply Service, Chemical Abstracts (CA Plus), Copyright Clearance Center’s Richard M. Slater, Christopher P. Smith, RightFind application, CrossRef, EBSCO (Academic Search International, Miranda E.J. Wells Discovery Service and TOC Premier), Gale/Cengage Learning Academic OneFile, GeoRef, Mineralogical Abstracts, ProQuest and the Thomson Reuters’ Branch Chairmen Emerging Sources Citation Index (in the Web of Science). Midlands – Georgina E. Kettle North East – Mark W. Houghton Copyright and Reprint Permission South East – Veronica Wetten Full details of copyright and reprint permission are given on The Journal’s website. 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 ISSN: 1355-4565 Cert no. TT-COC-002454 ii The Journal of Gemmology, 34(8), 2015 Editorial Good News for The Journal! For more than 60 years, The Journal of subscribed to by university libraries and Gemmology has been one of the top scientific research institutions worldwide. journals in gemmology. Receiving The Journal The Journal’s inclusion in WoS is good for is an important Gem-A membership benefit, our authors, for our readers and for gemmology and it provides a useful means of continuing in general. The Journal will now be in a better education for all gemmologists, in keeping position to attract articles from researchers at with Gem-A’s mission and values. The top universities who are required to publish scientific standing of scholarly publications in WoS journals, and our readers will benefit such as The Journal rests heavily on their from this cutting-edge research. In addition, selection for coverage by the international The Journal’s coverage by WoS will certainly research platform known as the Web of help raise awareness of gemmology in the Science.
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