mineral

Turquoise

Hydrated phosphate of copper and aluminum - CuAl6(PO4)4(OH)8·4H2O

AI-generated identification · may be incorrect

Hardness: 5-6 (Mohs scale), Color: Sky blue to apple green, Luster: Waxy to subvitreous, Crystal Structure: Triclinic (usually cryptocrystalline or massive), Cleavage: Perfect but rarely seen, Specific Gravity: 2.6–2.9

Identified March 4, 2026More mineral →

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Physical properties

Formation & geological history

A secondary mineral formed by the percolation of acidic aqueous solutions during the weathering and oxidation of pre-existing copper-bearing minerals in hydrothermal veins. Often found in arid regions within weathered igneous or sedimentary host rocks.

Uses & applications

Primarily used in jewelry for cabochons and beads. Also valued as a decorative stone in inlay work, as a collector's specimen, and for metaphysical purposes.

Geological facts

Turquoise has been prized for thousands of years; the Aztecs, Egyptians, and Native Americans all used it for masks and amulets. Its name comes from the French 'turquois', meaning 'Turkish', as it was first brought to Europe via Turkey from Persian mines.

Field identification & locations

Identify by its unique 'robin\'s egg' blue to green hue and waxy luster. Common locations include the Southwestern USA (Arizona, Nevada), Iran, and China. In the field, look for thin veins or crusts within weathered aluminum-rich rocks associated with copper deposits.