Hundreds of years before the Spanish explorers arrived, the Indians were mining and fashioning ornaments out of this gemstone in combination with shell and coral from the California coast they acquired in trading with other tribes.
Chemically, it is a phosphate of aluminum carrying small quantities of copper and iron and a green mineral, variscite. These give the gemstone its color as well as its value and beauty. This is the only phosphate that is considered a precious stone.
The Navajo and Pueblo Indians of the Southwest call turquoise chalchihuitl, as did the ancient peoples of Mexico and Central America who used the same word to describe jade or green turquoise. Turquoise set in silver by numerous silversmiths is a big industry in New Mexico and beautiful and authentic pieces may be purchased on reservations or at fashionable stores throughout the United States.
The State Legislature adopted the turquoise as the State Gem on March 23, 1967.