Antimony

Antimony is a chemical element with the symbol Sb and atomic number 51. It is classified as a metalloid—a substance with properties intermediate between metals and nonmetals. Its most common form is a brittle, lustrous solid with a silver-white color that breaks easily.

The symbol Sb derives from the Latin name stibium, which relates to the Arabic word ithmid, traditionally referring to the black powder historically used for darkening the eyes (kohl). Antimony is rarely found in pure form; its principal ore is stibnite, a compound of antimony and sulfur.

Chemical and Physical Properties

Antimony belongs to group 15 of the periodic table, the same group as arsenic and bismuth. It conducts heat and electricity poorly compared to true metals. It can exist in multiple oxidation states, notably +3 and +5. Antimony and its compounds are toxic when ingested or inhaled, and are therefore subject to workplace health regulations.

Industrial Applications

The largest use of antimony concerns antimony trioxide, added to plastics, textiles, and household goods as a flame retardant. Antimony is also added to lead to harden it—for example, in lead-acid battery plates for vehicles and in certain types of printing type. It is also used in semiconductors and electronic devices.

Production and Markets

Global antimony ore production is concentrated in a small number of countries, making many nations dependent on imports. Many countries and organizations include antimony on lists of critical raw materials, because of its importance in defense and industrial applications and the difficulty of substituting it. Recovery of antimony from recycled lead batteries is another source of supply.