Turquoise

Physical Properties

Hardness: 5-6 (Mohs scale); Color: Sky blue to blue-green; Luster: Waxy to subvitreous; Crystal Structure: Triclinic (usually massive or cryptocrystalline); Cleavage: Perfect (rarely seen due to fine grain size); Specific Gravity: 2.6-2.9.

Formation & Geological History

Formed by the percolation of meteoric water through copper-bearing aluminum-rich rocks. It is a secondary mineral usually found in arid regions, occurring as veins or crusts in altered volcanic rocks or sandstones. Formation can take millions of years.

Uses & Applications

Primarily used in jewelry making, gemstones, and ornamental carvings. It has been highly valued for thousands of years as a decorative stone in many cultures.

Geological Facts

Turquoise is one of the oldest gemstones in history, used by the Ancient Egyptians and Persians. Its name comes from the French 'turquois', meaning 'Turkish', as the stone was originally introduced to Europe via Turkey.

Field Identification & Locations

Identify by its unique sky-blue to greenish-blue color and waxy luster. In the field, look for it in arid climates associated with copper mines, often appearing as blue crusts in rock fractures. Common locations include Iran, the Southwestern United States, and China.

Identified on: 4/23/2026

Mode: Standard