Established in 1931, the Gemological Institute of America (GIA) is the world’s foremost authority on diamonds, colored stones, and pearls. A public benefit, nonprofit institute, GIA is the leading ...

如果您出生于六月，那么您很幸运，可以拥有三种生日石。六月是仅有的三个有三种生日石的月份之一（另外两个月份是八月和十二月），让您有各种各样美丽的生日石可以选择。 六月生日石是 ...

11月生まれの方は、2つの美しい誕生石、トパーズとシトリンからお好きなものを選ぶことができます。トパーズには虹のように様々な色があります。そしてシトリンには魅力的な黄色や ...

Emeralds are again being mined in the historic district of the Ural Mountains. Physical, chemical, spectroscopic, and microscopic characteristics of stones from the recent production are presented and ...

GIA is proud to provide the most comprehensive research in the industry with a world-renowned field gemology team and a dedication to acquiring colored stones directly from the source. Our ...

The GIA Laboratory-Grown Diamond Report includes full quality assessment with a plotted clarity diagram. Color and clarity specification are described on the same scale as the GIA Diamond Grading ...

Twenty-six peridot samples from the Esquel pallasite meteorite and 27 samples from 10 terrestrial sources were studied by laser ablation–inductively coupled plasma–mass spectrometry (LAICP- MS). Among ...

Reviews the advancements and major trends in laboratory-grown diamonds observed by GIA since 2007. Gemological and Trace Element Characteristics of Cassiterite from Yunling, China Examines gem-quality ...

This large Australian light opal cabochon weighs 117.85 carats. Small play-of-color flashes of orange and green predominate in a pinfire pattern, with spots of a more muted blue over a grayish ...

The Robert Mouawad Campus at GIA World Headquarters is the premier school for gem studies and jewelry design — featuring fully integrated modern classrooms and an internationally recognized museum at ...

As a consumer, you will regularly encounter in the marketplace gems that have been treated to change their appearance. A topic that often comes up is whether a particular gemstone is or isn’t treated.