Definition for AU'RUM

AU'RUM, n. [L. See Aurate.]

Gold. Aurum fulminans, fulminating gold, is gold dissolved in aqua-regia or nitro-muriatic acid, and precipitated by volatile alkali. This precipitate is of a brown yellow, or orange color, and when exposed to a moderate heat, detonizes with considerable noise. It is a compound of auric acid and ammonia. – Fourcroy. Aurum mosaicum, or musivum, a sparkling gold-colored substance, from an amalgam of quicksilver and tin, mixed with sulphur and sal-ammoniac, set to sublime. The mercury and part of the sulphur unite into a cinnabar, which sublimes with the sal-ammoniac, and leaves the aurum mosaicum at the bottom. It is a sulphuret of tin, and is used as a pigment. – Encyc. Nicholson.

Return to page 215 of the letter “A”.