64.—Smaltine.
Occurs in crystals and masses; metallic lustre; color tin-white to steel-gray; powder dark gray; brittle; gives off garlic odor in a candle; melted with borax makes a deep blue glass; gravity 6.5 to 7.
Value.—An ore of cobalt and arsenic, containing eighteen to seventy per cent.
Localities.—Found in veins in granite regions with other ores, Mine la Motte, Mo.; Chatham, Conn.
65.—Smithsonite.
Occurs in masses, often rounded, covered with minute crystals, or honeycombed; color white, dirty yellow or stone color; glassy lustre; brittle; effervesces in nitric acid; barely scratches glass; barely translucent; gravity 4.4.
Value.—Yields fifty per cent. of zinc.
Localities.—Found generally in limestone with galena and blende. Friedenville, Lancaster and Perkiomen, Pa.; Linden and Mineral Points, Wis.; Lawrence, County, Ark.; Ewing’s Diggings, Minn.
66.—Spathic Iron.
Occurs in crystals or plates somewhat curving; also (in coal regions) in nodules with concentric layers like an onion; brittle; color varies from white to yellowish-brown or dark-brown; strongly heated it blackens and will then attract the compass needle; the powder effervesces in nitric acid; melted with borax makes a green or yellow glass; gravity 3.8.