Phosphate · Turquoise

Turquoise

The December birthstone: copper-blue, waxy, porous and endlessly treated. Bench identification is easy (spot RI about 1.61), but the professional value question is which treatment, which mine, and what disclosure.

Colour
blue

Transparency
Opaque

RI
1.610–1.650

SG
2.40–2.90

Mohs
5.0–6.0

Birthstone
December

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Turquoise

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