gemstone

Turquoise

Hydrated copper aluminum phosphate, CuAl6(PO4)4(OH)8·4H2O

Hardness: 5 to 6 on the Mohs scale. Color: Blue, bluish-green, green, yellowish-green. Luster: Waxy to subvitreous. Crystal structure: Triclinic. Cleavage: Perfect in one direction, good in another, but rarely seen. Specific gravity: 2.60 to 2.90.

Hardness: 5 to 6 on the Mohs scale
Color: Blue, bluish-green, green, yellowish-green
Luster: Waxy to subvitreous

Identified August 2, 2026More gemstone →

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Physical properties

Formation & geological history

Forms by the action of descending meteoric waters percolating through copper-bearing aluminum rocks in arid climates. Geological age varies greatly depending on the deposit, typically found in weathered volcanic or sedimentary environments.

Uses & applications

Widely used in fine jewelry, rings, necklaces, inlay work, and ornamental carvings. Highly valued in Native American jewelry traditions.

Geological facts

Turquoise is one of the world's most ancient gem materials, prized by the ancient Egyptians, Persians, and Native Americans as a protective amulet and symbol of wealth.

Field identification & locations

Easily identified by its distinct robin's-egg blue or greenish-blue color often veined with dark limonite matrix. Commonly found in the southwestern United States, Iran, China, and Sinai.

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