What is Turquoise?


Turquoise is an opaque, blue-to-green mineral that is a hydrated phosphate of copper and aluminum. It’s primarily found in arid regions, including the southwestern United States and northern Mexico. Turquoise has been used for thousands of years and is known for its incredible variety of patterns and colors.

Turquoise is a blue-green mineral known for its unique hue and intricate patterns. Its striking appearance makes it a popular choice for jewelry and decorative items. The stone is often used in necklaces, bracelets, and earrings, and is sometimes used to make beads.

Gemstone Properties

Chemical ClassificationInorganic - Phosphate
ColorRanges from sky blue to green, depending on its copper and iron content.
LusterWaxy to subvitreous.
OccurrenceIran, United States (especially Arizona and Nevada), Mexico.
FormationTurquoise is typically formed by the leaching of copper in arid regions.
CleavageGood in one direction
Mohs Hardness5 to 6.
Specific GravityApproximately 2.60 to 2.90.
Diagnostic PropertiesBlue to green color, often with veins.
Chemical CompositionCuAl6(PO4)4(OH)8·4H2O
PleochroismNot exhibited in turquoise.
Crystal SystemTriclinic
Optical PropertiesBiaxial (+/-)
Refractive Index1.610 - 1.650
2V angleMeasured: 68°
DispersionNot typically relevant for turquoise.