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51. AntimonyName: Antimony
Metallic antimony is an extremely brittle metal of a flaky, crystalline texture. It is bluish white and has a metallic lustre. It is not acted on by air at room temperature, but burns brilliantly when heated with the formation of white fumes. It is a poor conductor of heat and electricity. Estimates of the abundance of antimony in the Earth's crust range from 0.2 to 0.5 ppm. Antimony is chalcophile, occurring with sulfur and the heavy metals lead, copper, and silver. Antimony was recognized in antiquity (3000 BC or earlier) in various compounds, and it was prized for its fine casting qualities. It was first reported scientifically by Tholden in 1450, and was known to be a metal by the beginning of the 17th century. The origin of the name "antimony" is not clear; the term may come from the Greek words "anti" and "monos", which approximately means "opposed to solitude" as it was thought never to exist in its pure form, or from the Arabian expression "Antos Ammon", which could be translated as "bloom of the god Ammon". The natural sulfide of antimony, stibnite, was known and used in Biblical times as medicine and as a cosmetic. stibinite is still used in some devloping countries as medicine. Antimony has been used for the treatment of schistosomiasis. Antimony attaches itself to sulfur atoms in certain enzymes which are used both by the parasite and human host. Small doses can kill the parasite without causing damage to the patient. The relationship between antimony's modern name and its symbol is complex; the Coptic name for the cosmetic powder antimony sulfide was borrowed by the Greeks, which was in turn borrowed by Latin, resulting in stibium. The chemical pioneer Jacob Berzelius used an abbreviation of this name for antimony in his writings, and his usage became the standard symbol. Antimony and many of its compounds are toxic. Clinically, antimony poisoning is very similar to arsenic poisoning. In small doses, antimony causes headache, dizziness and depression. Larger doses cause violent and frequent vomiting, and will lead to death in few days. Quick links
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