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27. CobaltName: Cobalt
Cobalt is a brittle, hard, transition metal with magnetic properties similar to those of iron. Cobalt is present in meteorites. Ore deposits are found in Zaire, Morocco and Canada. Cobalt-60 (60Co) is an artificially produced isotope used as a source of γ rays (high energy radiation). Cobalt salts colour glass a beautiful deep blue colour. Marmite, is a source of vitamin B12, actually a compound containing cobalt. The equivalent, but altogether blander, in Australia is Vegemite. Cobalt was known in ancient times through its compounds, which would color glass a rich blue. George Brandt (1694-1768) is credited with the discovery of cobalt. The date of discovery varies depending on the source, but is between 1730 and 1737. He was able to show that cobalt was the source of the blue color in glasses, which previously had been attributed to the bismuth found with cobalt. During the 19th century, cobalt blue was produced at the Norwegian Blaafarvev?rket (70-80 % of world production), led by the Prussian industrialist Benjamin Wegner. In 1938, John Livingood and Glenn Seaborg discovered cobalt-60. The word cobalt comes from the German kobalt or kobold, meaning evil spirit, the metal being so called by miners, because it was poisonous and troublesome (it polluted and degraded the other mined elements, like nickel). Some also think the name may derive from Greek kobalos, which means 'mine', and which may have common roots with kobold, goblin, and cobalt. Powdered cobalt in metal form is a fire hazard. Cobalt compounds should be handled with care due to cobalt's slight toxicity. Quick links
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