mineral

Turquoise

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

AI-generated identification · may be incorrect

Hardness: 5-6 Mohs; Color: Turquoise blue to green; Luster: Waxy to sub-vitreous; Crystal Structure: Triclinic (usually massive); Cleavage: Perfect (rarely seen in massive form); Specific Gravity: 2.6-2.9

Hardness: 5-6 Mohs
Color: Turquoise blue to green
Luster: Waxy to sub-vitreous

Identified June 9, 2026More mineral →

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Physical properties

Formation & geological history

Secondary mineral formed in the oxidation zone of copper deposits by percolating meteoric waters. Usually found in arid or desert climates inhabiting veins and cavities of altered vuggy rocks.

Uses & applications

Primarily used as a gemstone for jewelry, ornamental carvings, and in southwestern or ethnic decorative arts.

Geological facts

One of the oldest gemstones in human history, it was mined by Ancient Egyptians as early as 3000 BCE. Its color is derived from copper (for blue) or iron (for green).

Field identification & locations

Identify by its sky-blue to apple-green color and waxy luster. In the field, look for black or brown 'matrix' veins of limonite or sandstone. Found in Iran, SW United States (Arizona, Nevada), and China.