COBALT

(Co=59), lustrous, greyish white, ductile, metallic element, M.P. 1530°, occurring chiefly in smaltite or udite (CoAs;); obtained by converting the ores into oxides by roasting and reducing the latter by heating with carbon or aluminum. C. forms two. series of compounds, cobaltous and cobaltic, and complex salts with ammonia known as cobalt ammines, charac-— terized by their red or blue color. They are used as stains or pigments in pottery and gla -making.