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Fall 2007 Gems & Gemology VOLUME XLIII FALL 2007 Featuring: Transformation of the Cultured Pearl Industry Nail-Head Spicules in Natural Gems THE QUARTERLY JOURNAL OF THE GEMOLOGICAL INSTITUTE OF AMERICA ® Fall 2007 VOLUME 43, NO. 3 197 EDITORIAL ________ Save the Date for the 2009 Gemological Research Conference Alice S. Keller 199 LETTERS ________ FEATURE ARTICLES _____________ 200 From Single Source to Global Free Market: The Transformation of the Cultured Pearl Industry Carat Points Russell Shor Reviews the environmental and economic forces that have brought sweeping pg. 215 changes to the cultured pearl industry over the past 15 years. NOTES AND NEW TECHNIQUES ________ 228 A Study of Nail-head Spicule Inclusions in Natural Gemstones Gagan Choudhary and Chaman Golecha Reports on natural gems that contain nail-head spicule (or spicule-like) inclusions, which are typically associated with hydrothermal synthetic quartz and synthetic emerald. RAPID COMMUNICATIONS ________ 236 Copper-bearing Tourmalines from New Deposits in Paraíba State, Brazil Masashi Furuya pg. 240 240 Natural Type Ia Diamond with Green-Yellow Color Due to Ni-Related Defects Wuyi Wang, Matthew Hall, and Christopher M. Breeding REGULAR FEATURES _____________________ 244 Lab Notes Large cat’s-eye aquamarine • Dyed blue chalcedony detected by UV-Vis-NIR spectroscopy • A historic “piggyback” diamond • Natural type IIb blue diamond with atypical electroluminescence • An unsuccessful attempt at diamond deception • Kyanite resembling blue sapphire • Phenakite as a rough diamond imitation • Glass-filled synthetic ruby 252 Gem News International Large diamond mine to be developed in Saskatchewan, Canada • Spurious “spiral phantom” in diamond • Color-zoned axinite from Pakistan • Multi- colored fluorite from Brazil • Cr/V-bearing kyanite from Madagascar and else- where • Blue-green opal from Iran • A remarkably large fire opal carving • An pg. 246 unusually translucent non-nacreous pearl • A possible diamond inclusion in quartz from Diamantina, Brazil • An unusual type of phenomenal quartz • A new gemstone from Italy: “Violan quartz” • New sources of marble-hosted rubies in South Asia • Cr/V-bearing green spodumene from Afghanistan • Large beryl triplets imitating Colombian emeralds • Glass imitation of blue spinel • Dyed greenish blue chalcedony from Brazil • Conference reports 276 2007 Challenge Winners 277 Book Reviews 281 Gemological Abstracts pg. 269 ® EDITORIAL Editor-in-Chief Editor Editors, Lab Notes STAFF Alice S. Keller Brendan M. Laurs Thomas M. Moses [email protected] GIA, The Robert Mouawad Campus Shane F. McClure 5345 Armada Drive Managing Editor Carlsbad, CA 92008 Editor, Gem News International Thomas W. Overton (760) 603-4503 Brendan M. Laurs [email protected] [email protected] Technical Editor Editors, Book Reviews Associate Editor Sally Magaña Susan B. Johnson Stuart Overlin [email protected] Jana E. Miyahira-Smith [email protected] Thomas W. Overton Consulting Editor Circulation Coordinator Carol M. Stockton Debbie Ortiz Editors, Gemological Abstracts Contributing Editor (760) 603-4000, ext. 7142 Brendan M. Laurs James E. Shigley [email protected] Thomas W. Overton PRODUCTION Art Director Production Assistant Website: STAFF Karen Myers Allison DeLong www.gia.edu EDITORIAL Shigeru Akamatsu Jaroslav Hyr`´sl Thomas M. Moses REVIEW BOARD Tokyo, Japan Prague, Czech Republic New York, New York Edward W. Boehm A. J. A. (Bram) Janse Mark Newton Solana Beach, California Perth, Australia Coventry, United Kingdom James E. Butler Alan Jobbins George Rossman Washington, DC Caterham, United Kingdom Pasadena, California Alan T. Collins Mary L. Johnson Kenneth Scarratt London, United Kingdom San Diego, California Bangkok, Thailand John Emmett Anthony R. Kampf James E. Shigley Brush Prairie, Washington Los Angeles, California Carlsbad, California Emmanuel Fritsch Robert E. Kane Christopher P. Smith Nantes, France Helena, Montana New York, New York Henry A. Hänni Lore Kiefert Christopher M. Welbourn Basel, Switzerland New York, New York Reading, United Kingdom Subscriptions to addresses in the U.S. are priced as follows: $74.95 for one year (4 issues), $194.95 for three years (12 issues). SUBSCRIPTIONS Subscriptions sent elsewhere are $85.00 for one year, $225.00 for three years. Canadian subscribers should add GST. Special rates are available for GIA alumni and current GIA students. One year: $64.95 to addresses in the U.S., $75.00 else- where; three years: $179.95 to addresses in the U.S., $210.00 elsewhere. Please have your student or Alumni number ready when ordering. Go to www.gia.edu or contact the Circulation Coordinator (see above). Single copies of this issue (print or PDF) may be purchased for $19.00 in the U.S., $22.00 elsewhere. Discounts are given for bulk orders of 10 or more of any one issue. A limited number of back issues are also available for purchase. Please address all inquiries regarding subscriptions and single copy or back issue purchases to the Circulation Coordinator or visit www.gia.edu. To obtain a Japanese translation of Gems & Gemology, contact GIA Japan, Okachimachi Cy Bldg., 5-15-14 Ueno, Taitoku, Tokyo 110, Japan. Our Canadian goods and service registration number is 126142892RT. Gems & Gemology’s impact factor is 1.381 (ranking 11th out of the 26 journals in the Mineralogy category), according to DATABASE Thomson Scientific’s 2006 Journal Citation Reports (issued July 2007). Gems & Gemology is abstracted in Thompson Scientific 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, see www.gia.edu/gemsandgemology. Gems & Gemology welcomes the submission of articles on all aspects of the field. Please see the Guidelines for Authors on our MANUSCRIPT 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. COPYRIGHT Copying of the photographs by any means other than traditional photocopying techniques (Xerox, etc.) is prohibited without the express permission of the photographer (where listed) or author of the article in which the photo appears (where no photographer AND REPRINT is listed). For other copying, reprint, or republication permission, please contact the Managing Editor. PERMISSIONS Gems & Gemology is published quarterly by the Gemological Institute of America, a nonprofit educational organization for the gem and jewelry industry, The Robert Mouawad Campus, 5345 Armada Drive, Carlsbad, CA 92008. Postmaster: Return undeliverable copies of Gems & Gemology to GIA, The Robert Mouawad Campus, 5345 Armada Drive, Carlsbad, CA 92008. Any opinions expressed in signed articles are understood to be the opinions of the authors and not of the publisher. ABOUT The cultured pearl market, long dominated by the Japanese akoya, has expanded to include a wide variety of goods pro- duced throughout the Pacific region. In this issue, Russell Shor reviews the economic and environmental forces that have THE OVER C changed the cultured pearl industry over the past 15 years. Shown here are two examples of modern cultured pearl jewelry: a strand of 10–14 mm Tahitian and South Sea cultured pearls, and a bracelet set with Tahitian cultured pearls (8–10 mm) and diamonds. Courtesy of Mastoloni, New York. Photo by Harold & Erica Van Pelt. Color separations for Gems & Gemology are by Pacific Plus, Carlsbad, California. Printing is by Allen Press, Lawrence, Kansas. © 2007 Gemological Institute of America All rights reserved. ISSN 0016-626X Save the Date for the 2009 Gemological Research Conference ast year, more than 700 participants from 32 coun- deposits, diamond characterization, colored stone identifi- tries came to GIA’s first-ever Gemological Research cation, inclusions, new technologies, and more. Track 2 L Conference (GRC), in San Diego, California. Those will explore areas such as pearls and organic gems, color who attended the two-day conference or read the cover- description, jewelry manufacturing technology, market age of it in our Fall 2006 issue understand the caliber of research and analysis, gem pricing, gems in objects of cul- this international event. tural heritage, and jewelry history, among others. At this time, I am delighted to announce that the second Rounding out the 2009 GRC program are educational field Gemological Research Conference is set for August 21–23, trips to the gem pegmatite mines in San Diego County and 2009. This event, which is again being co-chaired by evening social events, including Gems & Gemology’s 75th Gems & Gemology editor Brendan Laurs and GIA distin- anniversary party. guished research fellow Dr. James Shigley, will also take place in San Diego, at the Town & Travel grants will again be avail- Country Resort and Convention able to selected presenters who Center. Participants will learn demonstrate appropriate need. about new technical develop- The GRC travel grant fund pro- ments and have the opportunity to vides financial assistance to wor- discuss the critical issues facing thy scientists who otherwise gemology with speakers and would not be able to participate. attendees from around the world. In 2006, grants were given to 20 deserving presenters from 12 For 2009, the GRC has been countries.
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