mineral
Turquoise
Turquoise (Hydrated phosphate of copper and aluminium), CuAl6(PO4)4(OH)84H2O
Hardness: 5–6; Color: Sky-blue to green-blue; Luster: Waxy to subvitreous; Crystal system: Triclinic; Cleavage: Perfect (rarely seen in massive forms); Specific Gravity: 2.6–2.9
- Hardness
- 5–6
- Color
- Sky-blue to green-blue
- Luster
- Waxy to subvitreous
Identified More mineral →
Explore Turquoise in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 5–6; Color: Sky-blue to green-blue; Luster: Waxy to subvitreous; Crystal system: Triclinic; Cleavage: Perfect (rarely seen in massive forms); Specific Gravity: 2.6–2.9
Formation & geological history
A secondary mineral formed by the percolation of acidic aqueous solutions during the weathering and oxidation of pre-existing minerals. Typically found in arid regions within volcanic rocks or sedimentary environments.
Uses & applications
Primarily used as a gemstone in jewelry (cabochons, beads, inlays) and for ornamental carvings. Historically significant in Native American and Persian cultures.
Geological facts
Turquoise is one of the oldest known gemstones, used by the Egyptians as early as 3000 BCE. Its name comes from the French 'turquois', meaning 'Turkish', as it first reached Europe via Turkey.
Field identification & locations
Identify in the field by its distinct robin's egg blue color and waxy appearance. Often found in veinlets or nodules. Collectors should look for 'Sleeping Beauty' or 'Kingman' varieties in the Southwestern USA.
More like this
Other mineral specimens
Sandstone (with potential mineral staining/concretions)
Arenite (SiO2 based)
sedimentary
Schist
Schist
Metamorphic
Epidote
Epidote | Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)
metamorphic
Gypsum (variety Selenite or Alabaster)
Calcium sulfate dihydrate (CaSO4·2H2O)
Mineral
Nephrite Jade
Nephrite
Mineral/Rock
Granite
Granite (Phaneritic intrusive igneous rock)
igneous