Turquoise

Physical Properties

Hardness: 5-6 (Mohs), Color: Blue to green (sky blue, teal, apple green), Luster: Waxy to subvitreous, Crystal structure: Triclinic (usually cryptocrystalline), Cleavage: None, Specific gravity: 2.6-2.9

Formation & Geological History

Formed by the percolation of acidic aqueous solutions through preexisting minerals during the weathering and oxidation of copper deposits in arid environments.

Uses & Applications

Primarily used in jewelry (cabochons, beads, inlay) and ornamental carvings; highly valued in Native American and Middle Eastern crafts.

Geological Facts

Turquoise is one of the oldest gemstones in human history; it was mined by Ancient Egyptians as early as 3000 BCE and used in the burial mask of King Tutankhamun.

Field Identification & Locations

Identify in the field by its distinct hue and waxy surface; often found in desert regions like the Southwestern US and Iran near limonite or copper sites.

Identified on: 5/13/2026

Mode: Standard