Antimony

[From Gr. anti, against, and monos, alone; so named from being seldom found alone.] ( Min. ) and Chem.) A metal of a silver-white color, with a good deal of lustre, found as native antimony, but chiefly in combination with arsenic, nickel, and silver; also in combination with oxygen as the trioxide, or valentinite or white antimony; with sulphur as stibnite or grey antimony, and with sulphur and oxygen, as kermisite or red antimony. The principal commercial source is the trisulphide or stibnite, from which the metal is obtained by roasting to convert it into the oxide, and then reducing by carbon. It fuses at 810°, or just at red heat. Its texture is fibrous or foliated; it is brittle and easily pulverized. When heated white hot by the blow-pipe, and thrown on the table, it burns and smokes, yielding an oxide. The principal properties of this metal were first discovered by Basil Valentine towards the end of the 13th century. There are three oxides of antimony. The trioxide Sb2°3, is a grayish-white powder, eminently purgative, sudorific, and emetic, and as such of much importance in medicine. It is the active base of emetic tartar and of James' Powder. The other oxides of antimony are the tetroxide, Sb2°4, and the pentoxide, Sb205, commonly called antimonic acid. The combination of chlorine and antimony was known to the chemists under the name of Butter of Antimony. The principal ore of antimony is the sulphide; it is met with in commerce, melted into conical ingots, under the name of crude antimony. It is of a bluish-gray color, metallic lustre, and a striated texture; sp. grav. 4:62. It is much more easily fusible than the pure metal.A. forms brittle alloys with some of the most malleable metals. When gold is alloyed with a 200th part of antimony, the compound is brittle; aud even the fumes of antimony in the vicinity of melted gold are sufficient to render it orittle. Alloyed with lead and tin and a small addition of copper, it forms type metal; with lead only a white and rather brittle compound is formed, used for engraving plates of music. With tin and zine, and sometimes copper, it forms the alloys of Britannia metal and pewter. With iron it form a hard whitish alloy formerly called martial regulus. A. is the Stimmi, or Stibium, of the old chemists. Until about 1882, the entire supply of antimony used in the United States was imported from Europe or from Germany; but its sulphide, known as stibnite, is now found here in very considerable quantities.