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 ...

The Karowe Diamond Mine in Botswana, owned and operated by Lucara Diamond Corp., has gained international recognition for producing large, high-quality type IaB or coexistence of IaB with IIa diamonds ...

Figure 1. The GIA 7 Pearl Value Factors system classifies pearls according to size, shape, color, luster, surface, nacre, and matching. Composite photo by GIA staff. Prized by many cultures throughout ...

In August 2022, a team of GIA gemologists visited the ruby mines near Montepuez in the Cabo Delgado province of northern Mozambique (Fall 2022 GNI, pp. 383–386). This included a visit to the deposits ...

GIA’s New York campus is a state-of-the-art facility in the International Gem Tower – right in the heart of the famed Diamond District. The campus is feet away from thousands of businesses devoted to ...

Through extensive hands-on practice using gemstones, you will explore grading the color, clarity and cut quality of a wide range of colored stones. Coursework includes the study of the GIA Colored ...

Practice the same time-tested procedures and identification skills used by the Institute’s renowned gemological experts. Tools used include a microscope, a refractometer with polarizing filter and a ...

GIA programs and courses are offered year-round on a rolling basis at GIA campuses around the globe. This enables students to jumpstart their gem and jewelry career studies at the soonest, most ...

Diamonds have a long history as a premier gemstone—a natural consequence of their beauty, rarity, and superlative physical properties such as extreme hardness. Diamonds that are mined for use as ...

A selection of the 406 Romanov jewels featured in Russia’s Treasure of Diamonds and Precious Stones by A.E. Fersman, 1925-26. GIA digitizes 200+ rare and historically significant books on gems and ...

Diamonds are the most amazing of gems. Just as amazing, however, is how natural diamonds reach Earth’s surface. Diamonds are formed 150 to 700 km deep in Earth, and are then carried upward in a rare ...