tur·quoise (tûrkwoiz′, -koiz′)
1. A blue to blue-green mineral of aluminum and copper, mainly CuAl6(PO4)4(OH)8·4H2O, prized as a gemstone in its polished blue form.
2. A light to brilliant bluish green.
[Middle English turkeis and French turquoise, both from Old French (pierre) turqueise, Turkish (stone), turquoise, feminine of turqueis, Turkish, from Turc, Turk; see TURK.]
(click for a larger image)turquoise
sterling silver and turquoise belt buckle
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