n. (Chem.) A tough, lustrous, reddish white metal of the iron group, not easily fusible, and somewhat magnetic. Atomic weight 59.1. Symbol Co. It occurs in nature in combination with arsenic, sulphur, and oxygen, and is obtained from its ores, smaltite, cobaltite, asbolite, etc. Its oxide colors glass or any flux, as borax, a fine blue, and is used in the manufacture of smalt. It is frequently associated with nickel, and both are characteristic ingredients of meteoric iron.
- A commercial name of a crude arsenic used as fly poison. Cobalt bloom. Same as Erythrite.
- Cobalt blue, a dark blue pigment consisting of some salt of cobalt, as the phosphate, ignited with alumina; - called also cobalt ultramarine, and Thenard's blue.
- Cobalt crust, earthy arseniate of cobalt.
- Cobalt glance. (Min.) See Cobaltite.
- Cobalt green, a pigment consisting essentially of the oxides of cobalt and zinc; - called also Rinman's green.
- Cobalt yellow (Chem.), a yellow crystalline powder, regarded as a double nitrite of cobalt and potassium.