GemmologyThe Journal of 2014 / Volume 34 / No. 4 The Gemmological Association of Great Britain Polish your knowledge A good understanding of diamond grading is essential for the buying, selling and trading of diamond. Our Diamond Diploma is recognized as one of the most comprehensive and valuable diamond qualifications worldwide — the ultimate education in diamonds. Graduates of our Diamond Diploma can apply for Diamond Membership, allowing you to use the letters ‘DGA’ after your name — a mark of excellence in the trade. Sign up now and receive our NEW fully illustrated Diamond Diploma course notes — updated to include the most current information and research on diamonds, as well as everything you need to get you started. For more information or to book 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. GemmologyThe Journal of 2014 / Volume 34 / No. 4 COLUMNS p. 354 279 What’s New GemmoFtir|GSJ abstracts| Historical facet designs|ICGL p. 295 and Margaritologia news- letters|Pearl presentations| Santa Fe Symposium pro- ceedings|Silver jewellery buying trends|Pueblo Gem & Mineral Show lectures 281 Practical Gemmology Visual Optics and the birefringence/dispersion ratio of gemstones 286 Gem Notes Almandine from Erving, ARTICLES Massachusetts|Amethyst from São Paulo State, Brazil|Apatite Feature Articles from Kenya|Colourless to 306 The Rhodesian Star: An Exceptional Asteriated near-colourless diopside from Diamond Canada and Kenya|Hessonite By Thomas Hainschwang, Franck Notari and Erik Vadaszi from Somalia|Polycrystalline kyanite from Tanzania|Green 316 Objective Diamond Clarity Grading daylight-fluorescent opal By Michael D. Cowing from Mexico|‘Trapiche’ quartz with radiating 334 A Comparison of R-line Photoluminescence of fibres|Yellow scheelite from Emeralds from Different Origins Pakistan|Spessartine from By D. Brian Thompson, Joshua D. Kidd, Mikko Åström, the DRC|CVD synthetic Alberto Scarani and Christopher P. Smith diamond in a parcel of yellow melee|Glass imitation of malachite|Dyed quartzite and Gemmological Brief chalcedony beads imitating 344 Green and Pink Tourmaline from Rwanda amazonite|News from By Ulrich Henn and Fabian Schmitz Myanmar 350 Conferences Gem-A Conference|GSSA Kimberley Diamond Symposium| Cover Photo: An 11.38 ct diamond NAJA Mid-year Conference|World of Gems Conference with an asteriated hydro- gen cloud is photo- 356 Gem-A Notices graphed under 250–350 nm broadband UV excit- ation. See article by 369 Learning Opportunities Thomas Hainschwang, Franck Notari and Erik Vadaszi on pages 372 New Media 306–315. Photo by T. Hainschwang. 378 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.2014.34.4 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, Gilching, Germany; Bear Williams, Stone Group Laboratories LLC, Jefferson Martin Rapaport 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, Colin Subscriptions 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/ Nigel B. Israel, Jonathan Lambert, advertising-in-the-journal.aspx. Richard M. Slater, Miranda E.J. Wells, Copyright and Reprint Permission 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. ™ © 2014 The Gemmological Association of Great Britain Understanding Gems Cert no. TT-COC-002454 ISSN: 1355-4565 ii The Journal of Gemmology, 34(4), 2014 What’s New What’s New INSTRUMENTS AND TECHNIQUES GemmoFtir The GemmoFtir, a new Fourier-transform infrared spectrometer developed specifically for gemmological analysis, was unveiled on 1 November 2014 at the Gem-A Conference in London. The instrument uses a gold-coated DRIFT sampling module and employs user- friendly software that follows the manufacturer’s philosophy of providing a consistent platform for manufactured together with Interspectrum, an all of its spectrometer products. The user interface Estonian company that has supplied spectrometers contains easy-to-follow acquisition wizards and for space stations. For more information, visit www. includes searchable spectral libraries for important gemmoraman.com/GemmoFtir.aspx. gem species and their color variations. The Alberto Scarani and Mikko Åström software also enables interactive peak labelling [email protected] and features applications for facilitating spectral M&A Gemological Instruments interpretation. The GemmoFtir was designed and Rome, Italy and Järvenpää, Finland NEWS AND PUBLICATIONS GSJ Abstracts gem cutter.