Peridot
Peridot is the gem variety of olivine, and Arizona's San Carlos Apache Reservation is one of the world's most important peridot sources — producing the vibrant olive-green stones used in jewelry worldwide. Peridot is one of the few gems that comes in only one color — its distinctive lime to olive green cannot be confused with any other gem. It also falls from the sky: peridot is found in certain meteorites (pallasite meteorites).
Physical Properties
Chemical Formula
Mg₂SiO₄ (gem variety of olivine)
Hardness (Mohs)
6.5–7
Color
Olive green, lime green, yellow-green
Luster
Vitreous
Crystal System
Orthorhombic
Streak
White to colorless
Cleavage
Imperfect
Specific Gravity
3.27–3.37
🔍 Field Identification Tips
Distinctive lime to olive green color (cannot be any other color — iron content controls the green). Vitreous luster with slight oiliness. Hardness 6.5–7. Conchoidal fracture. Often shows a doubling effect due to high birefringence (double refraction) visible with a loupe. Distinguished from green tourmaline by lower hardness and lack of striated crystals.
Varieties & Forms
📍 Where to Find Peridot in the US
Uses & Applications
Jewelry (August birthstone — one of the few gems found in only one color), collectors specimens.
💰 Collector Value Guide
Common rough: $5–$50/ct. Arizona medium green: $50–$200/ct. Fine olive green gems: $200–$1,000/ct.
Find Peridot With Our Tools
Use the We Lick Rocks app to identify specimens, find dig sites, and connect with local rockhounds.