Antimony

Antimony, chemical element, symbol Sb; for physical constants see Periodic Table. Substances containing antimony have been used for thousands of years as medicines and cosmetics. It was first characterized accurately by Nicolas Lémery in 1707. Its principal ore is stibnite, a sulfide. Antimony is obtained by roasting the sulfide to the oxide, which can be further reduced with carbon. It is an extremely brittle, bluish-white metalloid and a poor conductor of heat and electricity. Two allotropes of antimony are known. Antimony greatly increases the hardness and mechanical strength of lead. It is used in batteries, antifriction alloys, type metal, infrared detectors, diodes, and Hall-effect devices. Its compounds are used in safety matches, flame-proofing agents, paints, ceramic enamels, glass, and pottery. Antimony and its compounds are toxic.