Multi-Color-Zoned Quartz from Brazil
Yellow, Green, and Blue Sapphires Reportedly from Antang and Gombe, Nigeria
Nineteen sapphires of various colors, reportedly from sources in northern Nigeria, are studied in GIA’s Tokyo laboratory.
Synthetic Diamond Fraudulently Inscribed To Match Natural Diamond Report
A specimen seen in the Carlsbad lab for an updated diamond grading report does not match the previous documentation.
合成钻石的最新进展
James Shigley（詹姆斯·史格雷）博士是 GIA 的一位特聘研究员，也是钻石和钻石鉴定领域的重要专家之一。 在 2017 年拉斯维加斯 JCK 国际珠宝展演讲中，他分享了高温高压处理 (HPHT) 和化学蒸气沉淀法 (CVD) 合成钻石的最新进展
Characterization of Mg and Fe Contents in Nephrite Using Raman Spectroscopy
Evaluates the usefulness of Raman spectroscopy in distinguishing the color varieties of nephrite based on the relative ratio of Mg to Fe concentration.
An Update on Tourmaline from Luc Yen, Vietnam
Reviews the characteristics of tourmaline from pegmatites in the Luc Yen district of northern Vietnam.
Geology and Development of the Lomonosov Deposit, Northwestern Russia
Reviews diamond discoveries at the Lomonosov deposit, as well as the geology of the Arkhangelsk kimberlite province.
Carbonado Diamond: A Review of Properties and Origin
Presents a detailed examination of about 800 samples of carbonado diamond from Brazil and the Central African Republic, including possible models for its genesis.
Visit Europe’s First Diamond Mine
Photoluminescence Mapping of Optical Defects in HPHT Synthetic Diamond
Demonstrates the importance of this method in identifying diamond treatments, based on the
analysis of PL maps acquired from a brownish orange HPHT synthetic diamond.
Chart: Inclusions in Natural, Synthetic, and Treated Sapphire
Provides a visual guide to the internal features of natural, synthetic, and treated sapphires.
Big Sky Country Sapphire: Visiting Montana’s Alluvial Deposits
Documents a visit to the upper Missouri River and Rock Creek sapphire mining areas.
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