Turquoise
Bishop Mine
Campbell County, Virginia
This specimen measures 8cm x 12cm
Turquoise CuAl6(PO4)4(OH)8.4-5(H2O)
Phosphate; hydrous phosphate of copper and aluminum; may contain some iron
Color and Luster: Sky-blue, bluish green, apple-green; waxy, dull, streak white, pale green
Hardness: 5-6
Cleavage: None
Fracture: Conchoidal
Crystals: Triclinic; crystals rare; usually compact, reniform, stalactitic, incrusting, thin seams, disseminated
Note: This specimen was donated by the Micromineralogists of the National Capital Area, Inc. from the collection of Ruth Cole Wertz, 1992
Photo by Mary Sutherland
Descriptions taken from
The Audubon Society Field Guide to North American Rocks and Minerals