Turquoise

Turquoise is an opaque, blue-to-green mineral that is a hydrated phosphate of copper and aluminium, with the chemical formula CuAl₆(PO₄)₄(OH)₈·4H₂O. It is rare and valuable in finer grades and has been prized as a gemstone and ornamental stone for thousands of years owing to its unique hue.

Turquoise is perhaps the oldest stone in man's history, the talisman of kings, shamans, and warriors. It is a stone of protection, strong and opaque, yet soothing to the touch, healing to the eye, as if carved from an azure heaven and slipped to earth