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

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

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, ...

Gems & Gemology is the quarterly scientific journal of the Gemological Institute of America.

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.

Rose quartz is one of the many quartz varieties used as a gem material. It gets its name from its delicate pink color, which ranges from very light (almost white) to medium-dark.

To address concerns about laboratory-grown and treated diamonds being mixed into parcels of melee, GIA has developed an automated system to analyze and sort melee-size diamonds quickly and accurately.

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 ...

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, ...