mineral

Turquoise

Hydrous phosphate of copper and aluminium [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 occurs in massive or cryptocrystalline form), Specific Gravity: 2.6-2.9.

Identified March 24, 2026More mineral →

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Physical properties

Hardness: 5-6 (Mohs scale), Color: Sky-blue to apple-green, Luster: Waxy to subvitreous, Crystal structure: Triclinic (usually occurs in massive or cryptocrystalline form), Specific Gravity: 2.6-2.9.

Formation & geological history

Formed by the percolation of acidic aqueous solutions through weathered volcanic rocks. It is a secondary mineral usually found in arid regions, occurring in veins or crusts within host rocks like limestones or sandstones.

Uses & applications

Predominantly used as a gemstone for jewelry, including rings, necklaces, and traditional Native American silverwork. Also used for ornamental carvings and decorative inlays.

Geological facts

Turquoise is one of the oldest known gemstones, mined by Ancient Egyptians as early as 3000 BCE. Its name comes from the French 'turquois' meaning 'Turkish', as it was historically brought to Europe through Turkey.

Field identification & locations

Identify in the field by its distinctive 'robin's egg' blue or green hue and its association with copper deposits. Found in the Southwestern USA (Arizona, Nevada), Iran, and China. Collectors look for 'matrix' patterns (veins of host rock) and high saturation.