Bronze′-powder

Syn. Bronze . A name given to various powders having a rich metallic appearance, which they retain when applied on varnish, or when mixed with it, as in surface bronzing. Prep. 1. Gold-coloured :— a. From Dutch-foil, reduced to an impalpable power by grinding. Cheap and looks well, and is very durable when varnished. b. From gold-leaf, as the last. c. Precipitated powder of gold. d. From verdigris, 8 oz.; tutty powder, 4 oz.; borax and nitre, of each 2 oz.; bichloride of mercury, 1 ⁄ 4 oz.; grind them together, make the mixture into a paste with oil, and then fuse it; when cold, roll it into thin sheets or leaves, and grind it as in No. 1. 2. Iron-coloured :—Plumbago, in fine powder. 3. Red :—Sulphate of copper, 100 parts; carbonate of soda, 60 parts; mix, and apply heat until they unite into a ma ; then cool, powder, and add of copper filings, 15 parts; again well mix, and keep the compound at a white heat for about twenty minutes; lastly, when cold, reduce the ‘residuum’ to an impalpable powder, wash it in pure water, and dry it. 4. Silver :—Bismuth and tin, of each 1 oz.; melt them together, and add of quicksilver, 1 to 1 1 ⁄ 2 oz.; when cold, powder it. Obs. The above are used by painters, japanners, . See Bisulphide of Tin (Tin) , Powders , .