Ammolite: Iridescent Fossil Ammonite from Southern Alberta, Canada
SPRING 2001 VOLUME 37, NO. 1 EDITORIAL 1 The Dr. Edward J. Gübelin Most Valuable Article Award Alice S. Keller FEATURE ARTICLES pg. 5 4 Ammolite: Iridescent Fossilized Ammonite from Southern Alberta, Canada Keith A. Mychaluk, Alfred A. Levinson, and Russell L. Hall pg. 27 A comprehensive report on the history, occurrence, and properties of this vividly iridescent gem material, which is mined from just one area in Canada. 26 Discovery and Mining of the Argyle Diamond Deposit, Australia James E. Shigley, John Chapman, and Robyn K. Ellison Learn about the development of Australia’s first major diamond mine, the world’s largest source of diamonds by volume. 42 Hydrothermal Synthetic Red Beryl from the Institute of Crystallography, Moscow James E. Shigley, Shane F. McClure, Jo Ellen Cole, John I. Koivula, Taijin Lu, Shane Elen, and Ludmila N. Demianets pg. 43 Grown to mimic the beautiful red beryl from Utah, this synthetic can be identified by its internal growth zoning, chemistry, and spectral features. REGULAR FEATURES 56 Gem Trade Lab Notes • Unusual andradite garnet • Synthetic apatite • Beryl-and-glass triplet imitating emerald • Diamond with hidden cloud • Diamond with pseudo- dichroism • Surface features of synthetic diamond • Musgravite • Five- strand natural pastel pearl necklace • Dyed quartzite imitation of jadeite 64 Gem News International • White House conference on “conflict” diamonds • Tucson 2000: GIA’s diamond cut research • California cultured abalone pearls • Benitoite mine sold • Emeralds from Laghman, Afghanistan • Emeralds from Piteiras, Brazil • Educational iolite • “Hte Long Sein” jadeite • Kunzite from Nigeria • “Rainbow” obsidian • New production of Indonesian opal • Australian prehnite • “Yosemite” topaz • Tourmaline from northern Pakistan • A 23.23 ct tsavorite • TGMS highlights • Vesuvianite from California • Opal imitations • Green flame-fusion synthetic sapphire • Platinum coating of drusy materials • Gem display • Micromosaics 79 2001 Gems & Gemology Challenge 81 Book Reviews 83 Gemological Abstracts pg.
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