Rock Identifier
Natural turquoise (Turquoise — hydrated copper aluminum phosphate, CuAl₆(PO₄)₄(OH)₈·4H₂O) — mineral
mineral

Natural turquoise

Turquoise — hydrated copper aluminum phosphate, CuAl₆(PO₄)₄(OH)₈·4H₂O

AI-generated identification · may be incorrect

Hardness 5–6 Mohs; blue-green to green, typically waxy to subvitreous, opaque, and microcrystalline, with no prominent cleavage. The specimen shows turquoise color with dark brown matrix or host-rock inclusions.

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Physical properties

Hardness 5–6 Mohs; blue-green to green, typically waxy to subvitreous, opaque, and microcrystalline, with no prominent cleavage. The specimen shows turquoise color with dark brown matrix or host-rock inclusions.

Formation & geological history

Forms as a secondary phosphate mineral in arid, copper-rich, aluminum-bearing weathering zones, commonly replacing or filling fractures in host rock. Deposits are generally geologically young relative to the host rocks, often associated with Cenozoic oxidation and weathering.

Uses & applications

Used as a gemstone, cabochon, bead, inlay, and ornamental carving; also collected as a mineral specimen. Stabilized or dyed turquoise is common commercially.

Geological facts

Its blue color comes mainly from copper, while greener tones may reflect iron or dehydration. Major historic sources include Iran, the American Southwest, China, Chile, and Egypt.

Field identification & locations

Identify by its opaque blue-green color, waxy luster, low-to-moderate hardness, and porous texture; matrix patterns help distinguish localities. Avoid acids, heat, and prolonged water exposure.