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Fall 1995 Gems & Gemology

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Fall 1995 Gems & Gemology FALL 1995 VOLUME 31 NO 3 - TABLE 0 F CONTENTS EDITORIAL 1995 Challenge Winners LETTERS Gem-Quality Grossular-Andradite:A New Garnet from Mali Mary L. Johnson, Edward Boehm, Hoist Krupp, Joachim W. Zang, and Robert C. Kammerling Sapphires from Southern Vietnam Christopher P. Smith, Robert C. Kammerling, Alice S. Keller, Adolf Peretti, Kenneth V. Scarratt, Ngzzyen Dang Khoa, and Saverio Repetto NOTES AND NEW TECHNIQUES "Ti-Sapphire":Czochralski-Pulled Synthetic Pink Sapphire from Union Carbide Mary L. Johnson, Meredith E, Mercer, Emmanzzel Fritsch, Patricia Maddison, and James E, Shigley REGULAR FEATURES Gem Trade Lab Notes Gem News Book Reviews Gemological Abstracts ABOUT THE COVER: A new find ojwgarnets has been made in the Republic of Mali, western Africa. The lead article in this issue characterizes these garnets, which (ire primarily yellow-green to brown hut 17ls0 (rarely) intense green. They have conipo- sitions between grossular and andradite. The brooch contains Mali garnets, in a range of colors, and diamonds. The loose stones ruqe in size from the 1.35-ct yellow trinngle ciit to the 18.03-ct oval. The largest intense green stone is 2.90 ct. All stones and jewelry courtesy of Giislav Zang, Lapidary, ldar-Oberstein, Germany, jewelry design by Monikii Leyser, of Kirschweiler, near ldnr-Oberstein. Photo Q Harold s) Erica Van Pelt-Photographers, Los Angeles, CA. Typesetting [or Gems & Gcmology 1s by Graphix Express, SamMonicn, CA. Color separations are by Effective Graphics, Compton, CA. Printing is by Cadmus journal Services, Easton, MD. 0 1995 Gemological Institute of America All rights reserved ISSN 0016-626X Editor-in-Chief Editor Editors, Gem Trade Lab Notes Richard T.Liddicoat Alice S. Keller Robert C. Karnmerling 1660 Stewart St. C. W. Fryer Associate Editors Santa Monica, CA 90404 Editors, Gem News William E. Boyajian 421-7250 x25 1 (800) Robert C. Kaninierling Robert C. Kamnierling e-mail: [email protected] D. Vincent Manson John 1. Koivula John Sinlzankas Subscriptions Emmanuel Fritsch Jin Lim Cristina Chavira Editors, Book Reviews Technical Editor (800)42 1-7250 x20 1 Susan B. Johnson Carol M. Stockton Fax: (310) 453-4478 Jana E. Miyahira Assistant Editor Contributing Editor Editor, Gemological Abstracts Irv Dierdorff John 1. Koivula C. W. Fryer PRODUCTION Art Director Production Assistant Production Artist STAFF Christine Troianello Gail Young Carol Silver EDITORIAL G. Robert Crowningshielcl C. S. Hurlbut, Jr. A. A. Levinson REVIEWBOARD New York, NY Cambridge, MA Calgary, Alberta, Canada Alan T.Collins Alan Jobbins Kurt Nassau London, United Kingdom Caterharn, United Kingdom P.O. Lebanon, N{ Dennis Foltz Anthony R. Karnpf George Rossman Santa Monica, CA Los Angeles, CA Pasadena. CA Emmanuel Fritsch Robert E. Kane Kenneth Scarratt Santa Monica, CA Helena, MT Bangkok, Thailand C. W. Fryer John I. Koivula Karl Sclimetzer Santa Monica, CA Santa Monica, CA Petershausen. Germany Henry A. Hiinni James E. Shigley Base], Switzerland Santa Monica. CA SUBSCRIPTIONS Subscriptions in the U.S.A. arc priced as follows: $59.95 for one year (4 issues), $149.95 for three years (12 issues). Subscriptions sent elsewhere are S70.00 for one year, $180.00 for three years. Special annual subscription rates arc available for all students actively involved in a GIA program: $49.95, U.S.A.; $60.00, elsewhere. Your student number must be listed at the time your subscription is entered. Single issues may be purchased for $15.00 in the U.S.A., $18.00 elsewhere. Discounts arc given for bulk orders of 10 or more of any one issue. A limited number of back issues of GdG are also available for purchase. Please address all inquiries regarding subscriptions and the purchase of single copies or back issues to the Subscriptions Department. To obtain a Japanese translation of Gems eJ Gemology, contact the Association of Japan Gem Trust, Oiuchimachi Cy Bldg., 5-15-14 Ueno, Taito-Icu, Tokyo 110, Japan. Our Canadian goods and service registration number is R126142892. Gems 01 Gemology welcomes the submission of articles on all aspects of the field. Please see the Suggestions for Authors in the Spring 1995 issue of the journal, or contact the editor for a copy. Letters on articles published in Gems o1 Gemoloey and other relevant matters are also wclcome. COPYRIGHT 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 AND REPRINT classroom use without fee. Copying of the photographs by any means other than traditional photocopying tech- PERMISSIONS niques (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 is listed). For other copying, reprint, or republication per- mission please contact the editor. Gems 01 Gemology is published quarterly by the Gemological Institute of America, a nonprofit educational organi- zation for the jewelry industry, 1660 Stewart Street, Santa Monica, CA 90404. Postmaster: Return undeliverable copies of Gems ed Gemology to 1660 Stewart Street, Santa Monica, CA 90404. Any opinions expressed in signed articles are understood to be the opinions of the authors and not of the publishers. The Gems & Gemology Challenge has been one of our most popular annual features since its introduction nine years ago. This year was no exception. Hundreds of read- ers from all over the world took this demanding test, which appeared in the Spring 1 995 issue. Our heartfelt congratulations go to all who participated. Those who earned a score of 75% or better received a GIA Continuing Education Certificate rec- ognizing their achievement. Those listed below received a perfect 100% score. USA: Alabama William A. Lavender, Pelhain + Arizona Kenyon V. Painter, Scottsdale; Norma B. Painter, Scottsdale + California Chris Almquist, Santa Monica; Wendy Beckerson, Santa Monica; Rebecca Ann Bell, Joshua Tree; Kathylee Cook-Roberts, San Jacinto; Eddie Decsi, Santa Monica; Mary Fitzgerald, Santa Monica; Werner R. Hoehne, San Francisco; Claudia Jacobs, Santa Monica; Becka Johnson, Santa Monica; Hui-Ling Kuo, Santa Monica; Sherrie Kysillza, Santa Monica; Douglas R. Mays, Carmel; Catherine McIntyre, Santa Monica; Jana E. Miyahira, Santa Monica; Sina A. Mozafarian, Beverly Hills; Philip A. Owens, Santa Monica; Michael Pace, Elk Grove; Diane H. Saito, Santa Monica; Robert A. Seltzer, San Rafael; Glenn Shaffer, Julian; Judy Shechter-Lankford, Santa Monica; Karen B. Stark, Santa Monica; Judy Steinberg-Briclzer, Santa Monica; Jim Viall, Santa Monica; Teri Von Ende, Santa Monica; Dan Tzu-Tan Wang, Santa Monica; Phil Yurlziewicz, Santa Monica + Colorado Dale Winder;Ft. Collins 4 Connecticut William A. Jeffery, Westport + Florida Mathew Mooney, West Palm Beach; Timothy D. Schuler, Palm Harbor; John E. Williamson, Minis + Illinois Anne Blumer, Bloomington; John Jaeger, Bloomington 4 Massachusetts Mary B. Moses, West Newton 4 North Carolina Jean A. Marr, Kernersville; M. Lewis Nance, Fayetteville; Blair Tredwell, Advance + Nevada Terence E. Terras, Reno + New Jersey John Morlino, Jackson; Lynn Tully, Fanwood + New York Dorothy A. Buzzcll, Siiffern; Clifford H. Stevens, Gansevoort + Ohio Jean Mate, Mentor; Roy J. Pasini, North Olinsted; Jack Schatzley, Toledo + Pennsylvania Peter R, Stadelmeier, Yardley + Texas George L. Blair, Houston; Connie Bradshaw Copeland, Abilene + Virginia Dale S. Summers, Richmond 4 Washington Stephen H. Hall, Kennewiclz + Wisconsin Drew Thiet, Milwaukee; Thomas G. Wendt, Beaver Dam + AUSTRALIA: Malcolm B. Druery, Goonellabah; David A. Keith, Bethania + CANADA: Michael J. P. Cavanagh, Vancouver, British Columbia; Follzert H. De Jong, Victoria, British Columbia; Michael Hyszlza, Coolzstown, Ontario; Diane Kolze, Calgary, Alberta; David R. Lindsay, Bobcaygeon, Ontario; Lina Masse, Montreal, Quebec; Janysz J. Meier, Calgary, Alberta; Ron Plessis, Aldergrove, British Columbia; Jon C. Phillips, Vancouver, British Columbia + FRANCE: Marie-France Chateau, Paris + HONG KONG: Deidre I<. Alejo, Central + INDONESIA: Warli Latumena, Jakarta + ITALY: Mafalda Pasqui, Geneva; Roberto Filippi, Lucca; Gianfranco Zamboni, Agrate + SCOTLAND: James W. M. Heatlie, Edinburgh + SPAIN: Cristina Knorr, Vitoria + SWITZERLAND: Eva Mettler, Zurich + THAILAND: Johanne Cardin- Jack, Khon Kaen Answers (see pages 74-75 of the Spring 1995 issue for the questions): (1)a, (2)d, (3)a, (4)b, (5)c, (6)c, (7)b, (8)a, (9)b, (10)a, (11) b, (121 c, (13)d/ (14)c, (15)c, (16)bl (17)b, (18)dl (19)a, (201 b, (21)a, (22)dl (23)dl (24)c, (25)b. Our thanks to Warli Latumena of Jakarta for suggesting that we list the winners geographically. Challenge Winners GEMS & GEMOLOGY Fall 1995 149 Supb Rwsh beds Seem In August 1994, I visited &e ~-~~ r&n around Malpka with Dr. M&PWAthtbq-wddkWrn dythrough three ohidly reqpdgetnmpplie~ A0 Mhing Co,, the joht venture Emwal, d MRU {W- dewskee Rudouprawhie Ud).We toured the fad- tiwmdm-bedw&d&mdlwm quantities of mostly small faceted samples, including ddw,yellow to brown mddite gamts* da few demantoid garnets, in addition to emeralds and green beryls. One lot dm.dof appmxhwely 22 gmm ( 110 ct) of top-quality, richly colored rough emeraldsJdthough most weighed no more than 1-1.5 a. A few months aftex this visit, a Swiss buinewman with GI- conm&ns in he fama SkeiUniot~hught sevad lots of Urhemeralds to the GiibeIin Gem- Fall 1995 ~DWITE: A NEW GARNET FROM MALI By Mary L. Joh~~son,Edward Boehm, Horst Krupp, Joachim LV. Zang, and Robert C. Kammerling A find of new gem garnets has been made arnets have been prized as gems since at least 3200 in contact n~etamorphicdeposits in the B.C. (Andrews! 1991).Today! gem garnets are found Republic of Mali, western Africa. These in almost any color. They exhibit broad chemical vari- garnets, primarily yellow-green to brown ability between the lznown end-membersi the most but also (rarely) intense green, have compo- conlinon of which are pyropel almandii~e~spessartine! sitions between grossular and andradite.
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