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Spring 2006 Gems & Gemology G EMS & G VOLUME XLII SPRING 2006 EMOLOGY S PRING 2006 P AGES 1–94 “Paraíba” Tourmaline from Brazil, Nigeria, and Mozambique Lead Glass–Filled Rubies V Tortoise Shell OLUME 42 N O. 1 THE QUARTERLY JOURNAL OF THE GEMOLOGICAL INSTITUTE OF AMERICA ® Spring 2006 VOLUME 42, NO. 1 EDITORIAL _____________ 1 Symposium 2006: Navigating the Challenges Ahead Alice S. Keller 2 The Dr. Edward J. Gübelin Most Valuable Article Award FEATURE ARTICLES _____________ 4 “Paraíba”-type Copper-bearing Tourmaline from Brazil, Nigeria, and Mozambique: Chemical Fingerprinting by LA-ICP-MS Carat Points Ahmadjan Abduriyim, Hiroshi Kitawaki, Masashi Furuya, and Dietmar Schwarz Compares the chemical compositions of bright blue-to-green “Paraíba”- pg. 19 type tourmaline from the three known sources. 22 Identification and Durability of Lead Glass–Filled Rubies Shane F. McClure, Christopher P. Smith, Wuyi Wang, and Matthew Hall Reports on the identifying features of rubies filled with a high-lead-content glass to make them appear more transparent. 36 The Characterization of Tortoise Shell and Its Imitations Thomas Hainschwang and Laurence Leggio Documents the gemological properties of ornamental tortoise shell and its numerous imitations. pg. 26 REGULAR FEATURES _____________________ 54 Lab Notes Multicolored assembled stone • Diamond with “fingerprint” inclusions • Pink diamond with etch channels • Two diamonds from the same octahedron • Translucent brown-orange diamond • Inscriptions inside emerald crystals • Color-coated star quartz • Variscite, resembling turquoise 62 Gem News International 2006 Tucson report • Aquamarine from Sri Lanka • Massive haüyne-sodalite from Myanmar • Gem-quality massive pink muscovite from Brazil • Pyrope-spessartine pg. 60 from Tanzania • Transparent faceted sillimanite from India • Sphene from Pakistan • New spinel from Mahenge, Tanzania • Cuneiform aquamarine inclusion • “Blood trail” in copal • Colored fluid inclusions in quartz • “Platinum quartz” with star • New Madagascar mining laws • Black diamond with unusual growth structures • Sapphire with unusual color zoning • Väyrynenite from Pakistan • A convincing moonstone doublet • A rutilated quartz doublet • An unusual triplet • New CRJP Code of Practices • Update on the use of biological remains in gem materials 81 2006 Gems & Gemology Challenge 83 Book Reviews 85 Gemological Abstracts 94 The Last Page: The G&G Twenty-Five Year Index, 1981–2005 pg. 72 Symposium 2006: Navigating the Challenges Ahead he essence of navigation is simple: knowing where you are, knowing where you want to be, and chart- T ing a course to get there. But navigating today’s gem and jewelry industry requires something far beyond the tradi- tional map and compass. It requires knowledge, a strategic perspective on the industry and the world at large, and the willingness to embrace inevitable change. “Navigating the Challenges Ahead” is a fitting theme for GIA’s 4th International Gemological Symposium, Aug. 27–29, 2006, at the Manchester Grand Hyatt Hotel in San Diego, California. Informative sessions will examine the future of diamonds and colored stones, cultured pearls, jew- elry design and manufacturing, business perspectives, luxury retailing, e-commerce, and gem identification technology. The speaker lineup includes such visionaries as David Yurman, Nick Paspaley, Nadja Swarovski, François Curiel, and Robert Wan, as well as leading researchers such as Dr. George Rossman and Dr. Alan Collins. Symposium’s Debate Centers are fast-paced arenas where provocative industry leaders and audience members will tackle the industry’s For more information on Symposium, visit most controversial issues. State-of-the-art research will be on www.symposium.gia.edu or e-mail [email protected]. display at the ever-popular Poster Session, an interactive Visit the Gemological Research Conference at forum best described as a “Marketplace of New Ideas.” www.gia.edu/gemsandgemology or e-mail [email protected]. The event’s keynote speakers will deliver their perspectives on creativity, leadership, and innovation. This distinguished group features former U.S. Secretary of State Madeleine K. Albright, already registered to attend this scientific forum, one designed one of the most influential figures in geopolitics; Frank for the ardent student of gemology and the avid G&G reader. Abagnale, a former confidence man turned law enforcement consultant whose exploits were the basis of Steven Spielberg’s Rounding out the program are field trips to the world-famous “Catch Me If You Can”; and Deepak Chopra, renowned author Pala gem pegmatite district in San Diego County. These excur- and mind/body pioneer. Returning to Symposium for an sions will give a limited number of participants an opportunity unprecedented third closing address is Maurice Tempelsman, to tour the underground workings of three operating gem chairman of Lazare Kaplan International Inc. and a senior mines and join in lively discussions about the formation of statesman of the diamond industry. tourmaline, morganite, kunzite, and other gems with the mine owners and famous scientists in attendance. The academic program will be complemented by unforgettable evening events: GIA’s 75th Diamond Anniversary Gala at the Symposium and the GRC are unique events that offer an Institute’s headquarters in Carlsbad; a Sunset Soirée, with the experience unlike any other, one that will inform and inspire San Diego waterfront as its backdrop; and an Italian Jewelry you in charting your own course for a successful future. All Evening, where timeless fashion and creativity will come alive. of us at Gems & Gemology and GIA look forward to seeing you there. Another compelling reason to be in San Diego this August is GIA’s first-ever Gemological Research Conference (GRC), which is being held immediately before Symposium (Aug. 26–27) at the same site. Many of the brightest minds in gemology and related disciplines will be on hand to discuss the latest research on gem localities, geology of gem deposits, gem characterization techniques, and gem treatment and syn- Alice S. Keller thesis. As of this writing, with the event five months away, Editor-in-Chief, Gems & Gemology more than 200 people from some two dozen countries have Co-chair, 4th International Gemological Symposium EDITORIAL GEMS & GEMOLOGY SPRING 2006 1 ems & Gemology is pleased to announce the winners of this year’s G Dr. Edward J. Gübelin Most Valuable Article Award, as voted by the journal’s readers. We extend our sincerest thanks to all the subscribers who participated in the voting. The first-place article was “A Gemological Pioneer: Dr. Edward J. Gübelin” (Winter 2005), which examined the life and career of the eminent Swiss gemologist. Receiving second place was “Characterization and Grading of Natural-Color Yellow Diamonds” (Summer 2005), a study of the gemological and spectroscopic properties of these diamonds. Third place was awarded to “A Review of the Political and Economic Forces Shaping Today’s Diamond Industry” (Fall 2005), which chronicled the key developments that have transformed the diamond industry in the past 15 years. The authors of these three articles will share cash prizes of $2,000, $1,000, and $500, respectively. Following are brief biographies of the winning authors. Congratulations also to Prateek R. Jhaveri of Arusha, Tanzania, whose ballot was drawn from the many entries to win a five-year subscription to Gems & Gemology. Robert E. Kane Edward W. Boehm FIRST PLACE AGEMOLOGICAL PIONEER: DR. EDWARD J. GÜBELIN Robert E. Kane, Edward W. Boehm, Stuart D. Overlin, Dona M. Dirlam, John I. Koivula, and Christopher P. Smith Robert E. Kane is president and CEO of Fine Gems International in Helena, Montana, and a member of the G&G Editorial Review Board since 1981. A Stuart D. Overlin Dona M. Dirlam former director of the Gübelin Gem Lab in Lucerne, Switzerland, Mr. Kane is well known for his many lectures and articles on diamonds, gemstones, and gem identification. Edward W. Boehm is a gem dealer, consultant, and president of JOEB Enterprises in Solana Beach, California. Mr. Boehm holds degrees in geology and German from the University of North Carolina in Chapel Hill. Stuart D. Overlin is associate editor of Gems & Gemology and has been with the journal since 1997. Mr. Overlin received a bachelor’s degree in political science from the U.S. Naval Academy. Dona M. Dirlam is director of GIA’s Richard T. Liddicoat Gemological Library and Information Center in Carlsbad, California. A longtime contributor to G&G, Ms. Dirlam John I. Koivula Christopher P. Smith holds a bachelor’s degree in earth sciences from the University of Minnesota 2 MOST VALUABLE ARTICLE AWARD GEMS & GEMOLOGY SPRING 2006 at Minneapolis and a master’s in geology and geophysics from the University of Wisconsin at Madison. John I. Koivula is chief gemologist at the American Gem Trade Association (AGTA) Gemological Testing Center in Carlsbad. A prolific author, Mr. Koivula has spent more than 40 years photographing inclusions in gems. He holds bachelor’s degrees in chemistry and mineralogy-geology from Eastern Washington State University. Christopher P. Smith is director of identification services at the GIA Laboratory in New York and a member of the G&G Editorial Review Board. Formerly director of the Gübelin Gem Lab, Mr. Smith has written numer- ous articles for G&G and other publications. SECOND PLACE CHARACTERIZATION AND GRADING OF NATURAL-COLOR YELLOW DIAMONDS John M. King, James E. Shigley, Thomas H. Gelb, Scott S. Guhin, Matthew Hall, and Wuyi Wang John M. King is technical director of the GIA Laboratory in New York and John M. King James E. Shigley a frequent writer and lecturer on colored diamonds. Mr. King received his Master of Fine Arts degree from Hunter College, City University of New York. James E. Shigley is director of GIA Research in Carlsbad. The editor of Gems & Gemology in Review: Synthetic Diamonds (2005) and a con- tributing editor to the journal, Dr. Shigley received a bachelor’s degree in geology from the University of California, Berkeley, and a doctorate in geology from Stanford University.
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