 Mask of Xiutecuhlti, god of fire | Turquoise is believed to have been discovered in northeastern Persia around 4000 B.C. Turquoise is an opaque, blue-to-green mineral that is a hydrated phosphate of copper and aluminium. It is rare and valuable in fine grades and has been prized as a gemstone and ornamental stone for thousands of years. Turquoise was among the first gems to be mined. |  Aztec turquiose |
 | Turquoise has adorned the rulers of Ancient Egypt, the Aztecs, Persia, Mesopotamia, the Indus Valley, and in ancient China since at least the Shang Dynasty. In many cultures turquoise was a holy stone, a bringer of good fortune or a talisman to ward off misfortune. |  |
