mineral

Turquoise

CuAl6(PO4)4(OH)8·4H2O (Hydrated copper and aluminium phosphate)

AI-generated identification · may be incorrect

Hardness: 5-6 Mohs; Color: Sky-blue to green; Luster: Waxy to subvitreous; Crystal Structure: Triclinic (usually massive); Cleavage: Perfect (rarely seen)

Hardness: 5-6 Mohs
Color: Sky-blue to green
Luster: Waxy to subvitreous

Identified April 28, 2026More mineral →

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Physical properties

Hardness: 5-6 Mohs; Color: Sky-blue to green; Luster: Waxy to subvitreous; Crystal Structure: Triclinic (usually massive); Cleavage: Perfect (rarely seen)

Formation & geological history

Formed by the percolation of acidic aqueous solutions during the weathering and oxidation of pre-existing minerals; often found in arid regions within volcanic rocks or sedimentary phosphate deposits.

Uses & applications

Primarily used for jewelry, decorative carvings, and as a popular semi-precious gemstone for collectors.

Geological facts

Turquoise is one of the oldest known gemstones, used by the Ancient Egyptians and Persians. The blue color comes from copper, while green shades indicate the presence of iron.

Field identification & locations

Identifiable by its unique sky-blue to robin-egg blue color and often contains dark veins called 'matrix'. Found commonly in the Southwestern USA, Iran, and China.