Peridot is the name given to specimens of yellowish green to bright green olivine that are suitable for producing gems. Peridot serves as the birthstone for the month of August, and that contributes to its customer awareness and popularity.

Most gem-quality peridot is found in basalt flows, limestones, and dolomites. Much of the world’s commercial-quality peridot is mined at the San Carlos Reservation in Arizona. There, a few basalt flows contain nodules of granular olivine that are the source of peridot. This peridot is sent to Asia for cutting and returned to the United States mounted in department store jewelry. Higher quality peridot forms as large crystals during the metamorphism of limestone and dolomite. These deposits are located in Pakistan and Myanmar.

Pallasite meteorites often contain gem-quality crystals of olivine that can be cut into small but interesting gemstones. These are some of the few gemstones on Earth that have an extraterrestrial origin. They are usually small, extremely expensive gems but tremendously interesting.