COBALT

n. Ko'baMt. Lat., cobaltum. Fr., c. Ger., Kobalt (from Kobold, a goblin supposed to haunt the mines). It., Sp., cobalto. 1. A metallic element discovered by Brandt in 1742. It occurs in various forms of combination in the mineral kingdom. It is a very tough, hard, slightly malleable metal, having the lustre of polished iron and melting at the same temperature as that metal, or a little higher. It po e es magnetic properties. Its sp. gr. is variously stated at from 8'5 to 87. It forms compounds bearing a chemical resemblance to those of iron, and in composition is either bivalent (forming cobaltous compounds) or trivalent (forming cobaltic or coboltoso-cobaltic compounds). Symbol, Co; atomic weight 58'6. It is rarely used in its pure condition in medicine or pharmacy. 2. A commercial name for a variety of arsenic ore. See KOBALT and COBALTUM (2d def.). [B, 3, 5, 77, 158 (a, 24).] Azotate de c. (Fr.). See C. nitrate. Bisulfure tie c. (Fr.). See C. Bisulphide. Black c. Asbolite; a dark earthy oxide of cobalt. [B; Dana (a, 24).] Bleu de c. (Fr.). See C. ultramarine. Bromure de c. (Fr.). See C. bromide. Chlorure de c. (Fr.). See C. chloride. C. a mouches (Fr.). Fly-stone. [B, 5 (a, 24).] C. and pota ium cyanides. Double compounds of c. and pV>ta ium with cyanogen. They include: (1) pota ic cobaltous cyanide (Ger., Kaliurn kobaltciianiir), KiCofCNtg; (2) pota ium cobaltic cyanide, or pota ic cobaltic cyanide (Ger., Kaliumkobaltidcyanur, Kobaltidciiankalium), KgCoj(CN),.,. The former occurs as deep-red, deliquescent, E. he: E, ell; G, go; I, die; I", in; N, in; N", tank; [s. 322]