70.—Strontianite.

Occurs in crystals and in fibrous or granular masses; glassy lustre; brittle; thin pieces melt before a blow-pipe tinging the flame red; effervesces with acids; gravity 3.6.

Value.—A source of nitrate of strontia used in fire-works.

Localities.—Found in limestone. Schoharie, Muscalonge Lake, Chaumont Bay and Theresa, N. Y.