Summer 2010 Gems & Gemology
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G EMS & G VOLUME XLVI SUMMER 2010 EMOLOGY S UMMER 2010 P AGES 79–164 V OLUME The Wittelsbach-Graff and Hope Diamonds . Opals from Ethiopia—and Madagascar 46 Composite Turquoise . Microtomography of Pearls . A New Gem, Hibonite N O. 2 THE QUARTERLY JOURNAL OF THE GEMOLOGICAL INSTITUTE OF AMERICA EXPERTISE THAT SPREADS CONFIDENCE. Because Public Education AROUND THE WORLD AND AROUND THE CLOCK. Happens at the Counter. ISRAEL 5:00 PM GIA launches Retailer Support Kit and website Cutter checks parameters online with GIA Facetware® Cut Estimator. NEW YORK 10:00 AM GIA Master Color Comparison Diamonds confi rm color quality of a fancy yellow. CARLSBAD 7:00 AM MUMBAI 7:30 PM Laboratory technicians calibrate Staff gemologist submits new fi ndings on measurement devices before coated diamonds to GIA global database. the day’s production begins. HONG KONG 10:00 PM Wholesaler views grading results and requests additional services online at My Laboratory. JOHANNESBURG5:00 PM Diamond graders inscribe a diamond and issue a GIA Diamond Dossier® A $97.00 value, shipping and handling extra. All across the planet, GIA labs and gemological reports are creating a common language for accurate, unbiased gemstone evaluation. From convenient locations in major gem centers, to frontline detection of emerging treatments and synthetics, GIA’s Retailer Support Kit has been developed to help to online services that include ordering, tracking, and report previews — GIA is pioneering the technology, tools and talent sales associates educate the public about diamonds, that not only ensure expert service, but also advance the public trust in gems and jewelry worldwide. the 4Cs, and thoroughly explain a GIA grading report. WWW.GIA.EDU Take full advantage of all that GIA has to offer by visiting www.retailer.gia.edu To order your FREE kit, log on to www.retailer.gia.edu CARLSBAD NEW YORK LONDON ANTWERP FLORENCE GABORONE JOHANNESBURG DUBAI MOSCOW MUMBAI BANGKOK HONG KONG TAIPEI SEOUL OSAKA TOKYO RTGG08 Summer 2010 Volume 46, No. 2 ® EDITORIAL __________________ 79 GIA Symposium 2011: Advances in Gemological Research Alice S. Keller FEATURE ARTICLES __________________ 80 The Wittelsbach-Graff and Hope Diamonds: Not Cut from the Same Rough Eloïse Gaillou, Wuyi Wang, Jeffrey E. Post, John M. King, James E. Butler, Alan T. Collins, and Thomas M. Moses Two famous diamonds are tested to see if they originated from the same crystal. 90 Play-of-Color Opal from Wegel Tena, Wollo Province, Ethiopia pg.81 Carat Points Benjamin Rondeau, Emmanuel Fritsch, Francesco Mazzero, Jean-Pierre Gauthier, Bénédicte Cenki-Tok, Eyassu Bekele, and Eloïse Gaillou Describes a major new source of high-quality opal with a mostly white bodycolor. NOTES & N EW TECHNIQUES ______________ 106 A New Type of Composite Turquoise Gagan Choudhary 114 New Occurrence of Fire Opal from Bemia, Madagascar Martina Simoni, Franca Caucia, Ilaria Adamo, and Pietro Galinetto 122 X-ray Computed Microtomography Applied to Pearls: Methodology, Advantages, and Limitations Stefanos Karampelas, Jürgen Michel, Mingling Zheng-Cui, Jens-Oliver Schwarz, Frieder Enzmann, Emmanuel Fritsch, Leon Leu, and Michael S. Krzemnicki 128 X-ray Computed Microtomography: Distinguishing Natural Pearls from Beaded and Non-Beaded Cultured Pearls Michael S. Krzemnicki, Sebastian D. Friess, Pascal Chalus, Henry A. Hänni, and Stefanos Karampelas pg. 91 RAPID COMMUNICATIONS _______________ 135 Hibonite: A New Gem Mineral Thomas Hainschwang, Franck Notari, Laurent Massi, Thomas Armbruster, Benjamin Rondeau, Emmanuel Fritsch, and Mariko Nagashima REGULAR FEATURES _________________________ 139 Thank You, Donors 140 Lab Notes Unusual polyphase inclusions in corundum • Black diamond with solid CO 2 micro-inclusions and phosphores - cent zones • Fancy Vivid blue HPHT-treated diamond • Interesting display of the H3 defect in colorless dia - mond • CVD synthetic diamond over one carat • Synthetic diopside in manufactured glass • Green Be-diffused sapphire • Heat-treated spinel 147 Gem News International Unusual facet arrangement produces scalloped appearance in diamond • Chrysocolla chalcedony from Peru • Recent finds of kunzite in Pala, California • Natural pearls of the Pectinidae family • More on ruby from Cabo Delgado, Mozambique • Update on ruby, sapphire, and spinel mining in Vietnam • Sphene from northern Pakistan • Spinel from Bawma, Myanmar • Green garnets reportedly from Afghanistan • Calcium niobium gallium garnet • Glass imitations of emerald • “Nanogems,” a new synthetic • Serpentine doublets, sold as pietersite • Composite coral bangle • Lead glass–filled ruby in antique jewelry • Gems set with colored adhesive S1 Book Reviews pg. 159 S4 Gemological Abstracts www.gia.edu/gandg EDITORIAL Editor-in-Chief Editor Editors, Lab Notes STAFF Alice S. Keller Brendan M. Laurs Thomas M. Moses [email protected] Gemological Institute of America Shane F. McClure The Robert Mouawad Campus Managing Editor 5345 Armada Drive Editor, Gem News International Thomas W. Overton Carlsbad, CA 92008 Brendan M. Laurs [email protected] (760) 603-4503 Associate Editor [email protected] Editors, Book Reviews Stuart D. Overlin Susan B. Johnson Circulation Coordinator [email protected] Jana E. Miyahira-Smith Martha Rivera Thomas W. Overton Consulting Editor (760) 603-4000, ext. 7142 Carol M. Stockton [email protected] Editors, Gemological Abstracts Contributing Editor Brendan M. Laurs James E. Shigley Thomas W. Overton PRODUCTION Art Director Image Specialist G&G Online: STAFF Nanette Newbry, Studio 2055 Kevin Schumacher gia.metapress.com EDITORIAL Ahmadjan Abduriyim Emmanuel Fritsch Robert E. Kane Kenneth Scarratt Tokyo, Japan Nantes, France Helena, Montana Bangkok, Thailand REVIEW BOARD Shigeru Akamatsu Jaroslav Hyr`sl Lore Kiefert James E. Shigley Tokyo, Japan Prague, Czech Republic Lucerne, Switzerland Carlsbad, California Edward W. Boehm A. J. A. (Bram) Janse Michael S. Krzemnicki Christopher P. Smith Chattanooga, Tennessee Perth, Australia Basel, Switzerland New York, New York James E. Butler E. Alan Jobbins Thomas M. Moses Wuyi Wang Washington, DC Caterham, UK New York, New York New York, New York Alan T. Collins Mary L. Johnson Mark Newton Christopher M. Welbourn London, UK San Diego, California Coventry, UK Reading, UK John L. Emmett Anthony R. Kampf George R. Rossman Brush Prairie, Washington Los Angeles, California Pasadena, California SUBSCRIPTIONS Copies of the current issue may be purchased for $35 in the U.S., $50 elsewhere. Online subscriptions are $74.95 for one year (4 issues), $194.95 for three years (12 issues). Combination print/online subscriptions are $139.95 in the U.S. and $160 elsewhere for one year, and $399.95 in the U.S. and $465 elsewhere for three years. Canadian subscribers should add GST. Discounts are available for group subscriptions, renewals, GIA alumni, and current GIA students. Subscriptions include G&G’s monthly gemological e-newsletter, the G&G eBrief. To purchase subscriptions and single issues, visit store.gia.edu or contact the Circulation Coordinator. Electronic (PDF) versions of individual articles and sections from Spring 1981 forward can be purchased at gia.metapress.com for $12 each. To obtain a Japanese translation of Gems & Gemology, contact GIA Japan at [email protected]. Our Canadian goods and service registration number is 126142892RT. DATABASE Gems & Gemology’s impact factor is 1.172 (ranking 12th out of the 26 journals in the Mineralogy category), according to the Thomson Reuters 2008 Journal Citation Reports (issued July 2009). Gems & Gemology is abstracted in Thomson Reuters COVERAGE products (Current Contents: Physical, Chemical & Earth Sciences and Science Citation Index—Expanded, including the Web of Knowledge) and other databases. For a complete list of sources abstracting G&G, see www.gia.edu/gandg. ANUSCRIPT Gems & Gemology welcomes the submission of articles on all aspects of the field. Please see the Guidelines for Authors on M our Website, or contact the Managing Editor. Letters on articles published in Gems & Gemology are also welcome. SUBMISSIONS Abstracting is permitted with credit to the source. Libraries are permitted to photocopy beyond the limits of U.S. copyright law for private use of patrons. Instructors are permitted to photocopy isolated articles for noncommercial classroom use without fee. Copying of the photographs by any means other than traditional photocopying techniques (Xerox, etc.) is prohibited with- out the express permission of the photographer (where listed) or author of the article in which the photo appears (where no pho- tographer is listed). For other copying, reprint, or republication permission, please contact the Managing Editor. Gems & Gemology is published quarterly by the Gemological Institute of America, a nonprofit educational organiza- COPYRIGHT tion for the gem and jewelry industry. AND REPRINT Postmaster: Return undeliverable copies of Gems & Gemology to GIA, The Robert Mouawad Campus, 5345 Armada Drive, PERMISSIONS Carlsbad, CA 92008. Any opinions expressed in signed articles are understood to be the opinions of the authors and not of the publisher. ABOUT Identification of pearls—natural, bead-cultured, beadless-cultured, and “keshi”—has become more challenging than ever. Two articles in this issue, by Stefanos Karampelas and Michael Krzemnicki and coauthors, review the THE COVER use of X-ray computed microtomography in pearl analysis. The 31 natural pearls in this estate necklace range from 11.88 × 11.25 mm to 7.95 × 6.48 mm (courtesy of Mr. and Mrs. Mohammed