Peridot

Olivine (Mg, Fe)2SiO4

Rock Type: mineral

Peridot

Physical Properties

Hardness: 6.5–7.0 (Mohs scale); Color: Olive-green to lime-green; Luster: Vitreous (glassy); Crystal Structure: Orthorhombic; Cleavage: Poor; Specific Gravity: 3.27–3.37

Formation & Geological History

Formed deep in the Earth's mantle and brought to the surface by volcanic activity. It is one of the few gemstones that occurs in only one color. It is also found in pallasite meteorites.

Uses & Applications

Primarily used as a gemstone in jewelry (rings, necklaces, earrings). It is the birthstone for August.

Geological Facts

Ancient Egyptians called Peridot the 'gem of the sun.' It has been found in comet dust from the Stardust robotic spacecraft. It is the only gemstone found in meteorites that is large enough to be worn as jewelry.

Field Identification & Locations

Identify by its distinctive olive-green color and high birefringence (doubling of back facets). Commonly found in basaltic rocks, San Carlos Apache Reservation in Arizona, Pakistan, and Myanmar.

Identified on: 4/14/2026

Mode: Standard