Cultured Pearl Farming and Production in the Federated States of Micronesia
The current production of cultured pearls from the black-lipped pearl oyster (Pinctada margaritifera) in the Federated States of Micronesia includes mostly beaded as well as blister and nonbead-cultured pearls in a wide array of colors.
Summer 2012 Gem News International
Gemesis 公司的 CVD 合成钻石 (英语)
An examination of the gemological and spectroscopic properties of CVD synthetic diamonds from Gemesis Corp.
Precision Measurement of Inter-Facet Angles on Faceted Gems Using a Goniometer
A classic two-circle reflecting goniometer was used to measure inter-facet angles on five faceted diamonds that included round brilliants and fancy shapes.
Update on the Identification of Dye Treatment in Yellow or “Golden” Cultured Pearls
Dye treatments in yellow or “golden” cultured pearls have improved to the point that some samples show little surface evidence.
GIA’S Symmetry Grading Boundaries for Round Brilliant Cut Diamonds
A presentation of parameters used to support GIA's symmetry grading system.
Infrared Spectroscopy of Natural vs. Synthetic Amethyst: An Update
Identification of Extraterrestrial Peridot by Trace Elements
Twenty-six peridot samples from the Esquel pallasite meteorite and 27 samples from 10 terrestrial sources were studied by laser ablation.
Dyed Purple Hydrophane Opal
Opals with an unusual purple bodycolor and strong play-of-color have recently appeared in the market.
Research on Gem Feldspar from the Shigatse Region of Tibet
The existence of a natural red andesine deposit in China/Tibet has been the subject of controversy since 2006.
Brownish Red Zircon from Muling, China
Gem-quality brownish red zircon occurs in alluvium derived from Tertiary alkali basalt at Muling in the northeast Chinese province of Heilongjiang.
The Chinese Red Feldspar Controversy: Chronology of Research Through July 2009
Red copper-containing plagioclase feldspar from Oregon has been available for over a century.
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