turqoise

The substance has been known by many names, but the word //turquoise//, which dates to the 16th century, is derived from an Old french word for "Turkish", because the mineral was first brought to Europe from Turkey, from the mines in historical Khorasan Province of Iran.2345 Piny the elder referred to the mineral as //callais,// the Iranians named it "phirouzeh" and the Aztechs knew it as //Teoxihuitl//.
 * Turquoise** is an opaque, blue-to-green mineral that is a hydrous phosphate of copper and aluminum with the chemical formula CuAI6(PO)4(OH)8·4H2O It is rare and valuable in finer grades and has been prized as a Gem and ornamental stone for thousands of years owing to its unique hue. In recent times, turquoise, like most other opaque gems, has been devalued by the introduction of treatments, imitations, and synthetics onto the market.

By Emma