Winter 1989 Gems & Gemology
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WINTER 1989 Volume 25 No. 4 TABLE OF CONTENTS EDITORIAL Reflections on the 1980s Richard T Liddicoat FEATURE Emerald and Gold Treasures of the Spanish Galleon ARTICLES Nuestra Seiiora de Atocha Robert E. IZane, Robert C. IZammerling, Rhyna Moldes, John I. Koivula, Shane E McClure, and Christopher P. Smith Zircon from the Harts Range, Northern Territory, Australia Maxwell J Faulkner and lames E. Shigley Blue Pectolite from the Dominican Republic Robert E. Woodr~lf/and Emmanuel Fritsch NOTES Reflectance Infrared Spectroscopy in Gemology AND NEW E Martin, H. Merigoux, and P. Zecchini TECHNIQUES Mildly Radioactive Rhinestones and Synthetic Spinel-and-Glass Triplets Knit Nassau and Edward A, Lewand REGULAR Gem Trade Lab Notes FEATURES Gem News Book Reviews Gemological Abstracts Annual Index ABOUT THE COVER: During the 1600s the Spanish conquerors of the New Worldshipped tons of gold, silver, and copper back to their mother country. They also sent back thousands of carats of rough and jewel-set emeralds. This rosary was one of the many emerald treasurers b~oughtup from the sunken Nuestra Senora de Atocha during the past decade. It had been in its underwater tomb for over 350 years. Staff at the GIA Gem Trade Laboratory and their colleagues have examined several of the emerald and gold treasures recovered from the shipwreck; they report their gemological discoveries and observations on the goldwork in this issue. Photo by Shane i? McClure, CIA Gem Trade Laboratory, Santa Monica, CA. Typesetting for Gems & Gemology is by Scientific Composition, Los Angeles, CA. Color separations are by Effective Graphics, Compton, CA. Printing is by Waverly Press, Easton, MD. 0 1990 Gemological Institute of America All rights reserved ISSN 001 6-626X EDITORIAL Editor-in-Chief Editor Editor, Gem Trade Lab Notes STAFF Richard T. Liddicoat Alice S. Keller C. W. Fryer Associate Editors 1660 Stewart St. Editor, Gemological Abstracts Willian~E. Boyajian Santa Monica, CA 90404 Dona M. Dirlam Peter C. Kcller Telephone: (8001 421-7250 x25 1 D. Vincent Manson Subscriptions Editors, Book Reviews John Sinlzankas Bruce Tucker, Manager Elisc B. Misiorowslzi Technical Editor Telephone: (800)421-7250 x201 Loretta B. Loeb Fax: (213) 828-0247 Carol M. Stockton Editors, Gem News Editorial Assistant Contributing Editor John I. Koivula Nancy K. Hays John I. Koivula Robert C. Kammerling PRODUCTION Art Director Graphics Supervisor Word Processor STAFF Lisa Joko Robert Cultrera Ruth Patchick EDITORIAL Robert Crowningshield Robert C. Kammerling Sallie Morton REVIEW BOARD New York, LVY Santa Monica, CA Sun lose, CA Alan T Collins Anthony I<. Kampf Kurt Nassau London, United Kingdom Los Angeles, CA PO. Lebanon, N[ Dennis Foltz Robert E. Kanc Ray Pagc Santa Monica, CA Santa Monica, CA Santa Monica, CA Emmanuel Fritsch John 1. Koivula George Rossman Santa Monica, CA Santa Monica, CA Pasadena, CA C. W. Fryer Henry 0. A. Meyer Karl Schmetzer Santa Monica, CA West Lafayette, IN Heidelberg, W. Germany C. S. Hurlbut, Jr. James E. Shigley Cambridge, MA Santa Monica, CA SUBSCRIPTIONS Subscriptions in the U.S.A. are priced as follows: S39.95 for one year (4 issues), $94.95 for three years (12 issues). Subscriptions sent elsewhere are $49.00 for one year, S124.00 for thice years. Special annual subscription rates arc available for all students actively involved in a CIA program: $32.95 U.S.A., $42.00 elsewhere. Your student number must be listed at the time your subscription is entered. Single issues may be purchased for $10.00 in the U.S.A., $13.00 elsewhere. Discounts are given for bulk orders of 10 or more of any one issue. A limited number of back issues of G&G are also available for purchase. Please address all inquiries regarding subscriptions and the purchase of single copies or back issues to the Subs criptions Manager. For subscriptions and back issues in Italy, please contact Istituto Geinmologico ~Mcditerraneo,Via Marn~olaia#14, 1-38033, Cavalese TN, Italy. To obtain a Japanese translation of Gems el Gemology, contact the Association of Japan Gem Trust, Okachimachi Cy Bldg, 5-15-14 Ueno, Taito-ku, Tokyo 110, Japan. MANUSCRIPT Gems a) Gemology welcon~esthe submission of articles on all aspects of the field. Please see the Suggestions for SUBMISSIONS Authors in the Spring 1989 issue of the journal, or contact the editor for a copy. Letters on articles published in Gems sl Gemology and other rclcvant matters are also welcomc. COPYRIGHT Abstracting is permitted with credit to the source. Libraries are permitted to photocopy beyond the limits of U.S. AND REPRINT copyright law for private use of patrons. Instructors are permitted to photocopy isolated articles for noncon~mercial PERMISSIONS classroom use without fee. 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 is listed). For other copying, reprint, or republication pern~ission, please contact the editor. Gems d) Gen~ologyis published quarterly by the Ccn~ologicalInstitute of America, a nonprofit educational organization for the jewelry industry, 1660 Stewart St., Santa Monica, CA 90404. Postn~aster:Return imdeliverable copies of Gems a) Gemology to 1660 Stewart St., Santa Monica, CA 90404. An'y opinions exprcssed in signed articles are understood to bc the views of the authors and not of the publishers Reflections on the 1980s he past decade has been one of significant changes in the diamond and colored Tstone industry with a potential impact that is perhaps unparalleled in modern gemology. We began this decade with major upheavals in the diamond market and are ending it with that market stronger than ever. We have seen colored stones reach new heights in availability and consumer awareness. New localities have been found, as have several unusual varieties of old favorites (witness the new Paraiba tourmalines). Perhaps most challenging of all have been the technological advances: The broader use of heat treatment and irradiation, the application of a process that actually fills cleavages in diamond, the appearance of new synthetic emeralds and corundum, and the unprecedented commercial availability of gem- quality synthetic diamonds have brought new demands in gem identification and evaluation. They have also spurred the introduction of new techniques (infrared spectroscopy for one) into the gemology laboratory. t ' W; at Gems s? Gemology are proud to have published the first in-depth reports on many of these new localities, new treatments, new synthetics, and new identifica- tion techniques. The 1980s also marked the introduction of the larger format, full- color GdG, with a mandate to supply the most thorough and current gemological information to the international gem community. To close the 1980s and look forward to the final decade of the second millenium, we have asked a number of prominent gemologists and researchers to summarize the key developments of the last 10 years in gem localities, treatments, synthetics, technology and jewelry manufacturing and design, as well as provide a preview of the '90s. These articles will be presented in a special, expanded Spring 1990 issue and will serve as the springboard with which we plan to "face the future" at the June 1991 International Gemological Symposium, In the future, as we have in the past, Gems es) Gemology will continue to keep you informed of the latest and most significant events in this exciting field. Richard T. Liddicoat Editor-in-Chief Editorial GEMS &. GEMOLOGY Winter 1989 195 EMERALD AND GOLD TREASURES OF THE SPANISH GALLEON NUESTRA SENORA DE ATOCHA By Robert E. Kane, Robert C. Kammerling, Rhyna Moldes, John I. Koivula, Shane F. McClure, and Christopher l? Smith During the 1970s and 1980s, treasure uring the Spanish conquest of the New World in the hunters discovered the centuries-old re- D 1500s, conquistadores discovered vast amounts of mains of the sunken Spanish galleons valuable commodities such as gold, silver, copper, indigo, Nuestra Senora de Atocha and Santa Mar- pearls, and emeralds. The last of these, emeralds, was one of garita. Not only did they find massive the rarest items-with only the exhausted Egyptian de- amounts of silver and gold in coins, bars, posits then lznown to the Western world. Gold and silver and chains, but they also uncovered a number of rough emeralds and several were mined in Upper Peru (now Bolivia), Mexico, and the pieces of emerald-set jewelry. Recently, area that was eventually lznown as New Granada (Colom- some of the treasures recovered from the bia, parts of Venezuela, Ecuador, and Panama). In 1537, Atocha were examined at the Santa Gonzalo Jimenez de Quesada was pursuing his conquest of Monica office of the GIA Gem Trade Lab- the interior of Colombia when his men located emerald oratory. Gemological testing of the emer- deposits in an area then called Somondoco and later named alds revealed inclusions typical of stones Chivor. Subsequently, emerald deposits were also found at mined in Colombia as well as possible ev- Muzo, with its even larger (and, many consider, finer) idence of extended submersion in sew- crystals. The Spaniards quickly enslaved the local tribes ter. Study of the jewelry revealed a high- and forced them to work the mines, as they had done karat gold content and fine workmanship elsewhere (Keller, 1981). Many emeralds, both set in that represented methods typical of the era. jewelry and as rough crystals (figure l),were subsequently sent to Spain. Spain set up a sophisticated system of delivery and piclz- up to and from the New World and Asia using fleets of cargo vessels guarded by warships (Lyon, 1982; Mathew- ABOUT THE AUTHORS son, 1987). On September 4, 1622, the cargo vessels and Mr.