The best-known gem testing laboratory is, undoubtedly, the Gemological Institute of America, or GIA. It was founded in 1931 by Robert M. Shipley, and it asserts that its mission is “to protect all buyers and sellers of gemstones by setting and maintaining the standards used to evaluate gemstone quality”.

A gemology career requires no formal college degree. However, you'll need to take some trade classes to receive your certification. The International Gem Society offers an online Professional Gemologist certification course. The Gemological Institute of America offers a Graduate Gemologist program.

A nonprofit, public benefit research and educational institution, GIA is as an independent and impartial entity for evaluating the quality of gems and delivering unbiased information on them. We do not sell gemstones, nor do we represent the interests of gem sellers.

Gemologists identify a gemstone by its specific characteristics and properties, such as cut, color, quality, and clarity. Some rubies and garnets, for example, are impossible to distinguish by their appearance, but their underlying physical properties differ considerably.