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

Yes. GIA has been grading laboratory-grown diamonds since 2007. Beginning July 1, 2019, GIA Laboratory-Grown Diamond Reports and identification reports no longer use the term “synthetic.” The GIA ...

Documents a series of visits to Myanmar in search of exceptionally bright pinkish red spinels possessing no dark tones.

GIA studied more than 400 important gemstones from the Gübelin Collection and is committed to sharing this repository of gemological information. This work is a valuable resource for all students, ...

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 ...

A guide describing frequently encountered gem treatment processes, their detection, and special care tips for treated gems.

Diamond is available in a range of sizes and qualities to fit every consumer's tastes. One of the first things most people learn about diamonds is that not all diamonds are created equal. In fact, ...

GIA Knowledge Sessions, a series of talks and seminars that promise to engage participants in the most diverse and pressing issues in gemology today, including gemstone origin, laboratory-grown stones ...

A new type of African chalcedony with the trade name “Aquaprase” shows unique composition and attractive color.

Heat treatment usually gives it a more bluish appearance. Aquamarine crystals are known to be large in size and relatively clean and well-formed, making them particularly valuable to collectors of ...

珍珠生日石的意义和历史 这一迷人的六月生日石产自世界各地的海洋、湖泊和河流。这是永不过时的衣柜必备品，深受所有年龄阶段的女性热爱。珍珠的来源让我们的祖先着迷。中东地区的古人认为珍珠是从天堂滴落的眼泪。中国的传说宣称六月生日石取自龙的大脑。克里斯多弗·哥伦布（Christopher ...

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, ...