Used as a gem since ancient times, turquoise is probably one of the oldest gem materials known to man. It was mined by the Egyptians more than 6,000 years ago, prized for its sky blue color by the Aztecs and Incas, and later by the Native Americans. It gets its name from the Old French "pierre Turquoise" or "stone of Turkey," in reference to the considerable Persian turquoise that was sold in Turkish markets. Copper colors turquoise blue, while iron impurities tint it green. This Navajo turquoise bracelet by Ondelacy is set in silver.