8.—Azurite.
Occurs in crystals and masses with glassy lustre, or earthy and dull; brittle; crackles and blackens, and finally fuses by heat; dissolves with effervescence in nitric acid; gravity 3.5.
Value.—A valuable ore of copper, containing sixty per cent.
Localities.—Found chiefly in lead and copper mines. Perkiomen lead mine, Cornwall, Phoenixville and Nicholson’s Gap, Pa; near New Brunswick, N. J.; near Mineral Point, Wis.; Polk County, Tenn.; Calaveras and Mariposa Counties, Cal.; near Virginia City, Mont.