Black Corded Round Turquoise Charged BraceletA single round Turquoise bead on a black cordminimal setting, maximum mineral. Turquoise is a copper aluminum phosphate, CuAl6(PO4)4(OH)84H2O, Mohs 56. Its sky to teal blue color comes from copper content; matrix veining visible across the stone's surface is the host rock in which it formed. Natural Turquoise is one of the oldest gemstones in continuous human use, and genuine specimensas opposed to stabilized, dyed, or simulated materialare