Antimony is a chemical element, classified as a metalloid. It has an atomic number of 51 and an atomic weight of 121.75. A member of group 15 on the periodic table, antimony can be found in or mined as black crystals from stibnite ore, which are often ground for medicinal use. Antimony can also be found in several minerals that contain its sulfide and telluride compounds. You may have heard of it in regards to its powdered form called "antimony powder", which was once used by artists for drawing purposes but is now largely obsolete with better options available today such as graphite or charcoal pencils.
Antimony is a naturally-occurring chemical element found in the earth's crust and in trace amounts in various plants, animals and humans. It was discovered over 3,000 years ago by the Egyptians who used it to produce makeup. Throughout history, antimony has been used as a poison and as medicine for headaches and skin problems. In addition to being chemically active, antimony can also be poisonous if it is released into the air by burning coal or oil. The chronic long-term health risks of exposure to antimony are not well understood but high levels of exposure have been shown to cause liver cancer and leukemia.
Antimony is a metalloid (a chemical element with properties between those of metals and non-metals, and lacking physical and chemical characteristics that can be predicted by the periodic table) with properties similar to those of arsenic, bismuth and tellurium. It is a brittle silvery-grey metal, which forms crystals that are resistant to acids. Antimony's crystalline structure has been identified as orthorhombic (space group Pbca), meaning it possesses three axes of unequal length with perpendicular or almost perpendicular planes of symmetry.
However, antimony's structure is actually very similar to that of bismuth: both elements are compounds of groups 13 and 14 in the periodic table. The lattice resembles a cross-section of a polyhedron, resembling a double-crossed six-sided star.
Antimony is a soft, brittle, lustrous silvery metal with an estimated value of about $1 USD per gram as estimated by 2010 prices. It is a heavy metal, requiring large amounts of heat to be formed into an ingot. It will tarnish rapidly in air and is resistant to water. Pure antimony is usually grey-black in color with a metallic sheen and a metallic taste. It has a density of 6.41 g/cm, making it the eighth densest transition metal. Its most notable properties are high electronegativity and numerous soft red oxidation states, but it also possesses some distinctive physical characteristics such as high melting point (634 °C; 1,060 K), high boiling point (2,943 °C; 5,078 K), and low freezing point.
Antimony is mostly used in making flame retardant materials, as a metallurgical additive for steel and cast iron to improve machinability, and as one of the semiconductors of lead telluride minerals.
Antimony's compounds have been used as folk remedies for centuries against organ disorders, skin eruptions such as acne, inflammations and wounds. In the 16th century it was added to wine to combat souring due to fermentation when water was in short supply during sieges or travels. The word "antimonious" means "antimony-like".
