![]() We get ours partly from food - sardines, salmon, liver, and eggs are good sources - and partly from the bacteria in our gut. Most animal species can make vitamin B 12, but not humans. Lack of this B 12 causes pernicious anaemia - the body cannot produce enough red blood cells to transport all the oxygen that it needs. For the bodyĬobalt is at the heart of vitamin B 12 where it is directly bonded to a methyl group one of the rare examples of a metal-to-carbon bond in nature. Cobalt catalysts are used in the chemical industry to convert syngas, a mixture of carbon monoxide and hydrogen, into liquid fuels. Alnico, an alloy of mainly of aluminium, nickel and cobalt, is used for permanent magnets that are very powerful although in small appliances neodymium-based magnets are now mainly used. However, it has the advantage of maintaining its magnetism to much higher temperatures iron demagnetises at 770☌ whereas cobalt's Curie point is at 1130☌. Some cobalt alloys are used in artificial body parts such as knee replacements and in dentistry.Ĭobalt can be magnetised, like iron, although it is less powerful. One alloy of cobalt, chromium, and tungsten is known as Stellite and is used for heavy duty high temperature cutting tools. Certain types of stainless steel contain it, including that used to make razor blades. Today cobalt comes mainly as a by-product of nickel production, and it is used in alloys for magnets, in ceramics, in catalysts and in paints. In 1730, the Swedish chemist Georg Brandt (1694-1768) began to investigate a similar ore found in a copper mine at Vestmanland and showed it was a hitherto unknown metal which he christened cobalt. They referred to the ore by the German name for these evil spirits, kobald (it was in fact smaltite, CoAs 2) and kobald eventually gave rise to the name of the metal itself. When, in the 1500s, silver miners in Saxony tried to smelt what they believed was a silver-bearing ore they were disappointed and cursed the mineral, saying it had been bewitched by goblins. Curiously, this element got its name by being cursed.
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