Provides a visual guide to the internal features of natural, synthetic, and treated spinel, as well as inclusions of spinel in other gemstones.

Colored Stone Identification & Origin Report An Identification Report, with geographic origin added. For polished, loose or mounted natural alexandrite, emerald, jade, Paraíba tourmaline, red spinel, ...

GIA developed this guide so retailers can use fluorescence tests to help identify gems right in their own stores.

Feature Gems & Gemology, Winter 1999, Volume 35, No. 4 Classifying Emerald Clarity Enhancement at the GIA Gem Trade Laboratory Shane F. McClure, Thomas M. Moses, and Maha Tannous, John I. Koivula ...

Amethyst may develop into the more common citrine and rarer green quartz naturally under certain geologic conditions. On the California-Nevada border, just north of Reno, amethyst, citrine, and green ...

GIA offers many opportunities for students to receive a scholarship. Scholarship offerings are made available to assist eligible students in reducing their financial burden and focusing on completing ...

Knowledge of the durability of a gemstone is critical to understanding the risks involved in the various setting, repair, and cleaning procedures commonly used by the jeweler. Some gemstones need ...

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Get details on the latest research from the GIA research team, including: natural diamond geology and mining locations, causes of colors and optical features, laboratory-grown diamond research, ...

Feature Gems & Gemology, Spring 2015, Vol. 51, No. 1 The Chinese Soul in Contemporary Jewelry Design Andrew Lucas, Merilee Chapin, Moqing Lin, and Xiaodan Jia ...

Synthetic moissanite is much closer to diamond in overall appearance and heft than any previous diamond imitation; this article reports on how to identify and characterize it.

Provides a visual guide to the internal features of natural, treated, synthetic, and imitation opal.