Turquoise
Mineral CuAl6(PO4)4(OH)8·4H2O
Also called Calaite
Take care.
- Sensitive to heat: Keep it away from heat and sudden changes of temperature, including hot lights and ultrasonic cleaners.
About it
Opaque sky-blue to green nodules and veins with a waxy look, often laced with dark matrix. Mined in Iran, Arizona, Nevada, New Mexico, and China; much on the market is dyed or stabilized.
- Type
- Mineral
- Group
- Phosphate, turquoise group
- Formula
- CuAl6(PO4)4(OH)8·4H2O
- Hardness (Mohs)
- 5–6
- Specific gravity
- 2.6–2.9
- Streak
- white to pale green
- Lustre
- waxy, subvitreous, dull
- Crystal system
- Triclinic
- Colours
- sky blue, blue-green, apple green, greenish grey
- Transparency
- opaque, translucent
- Cleavage and fracture
- none in masses; conchoidal fracture
Typical values: real specimens vary. For more, see mindat.org.