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Many artifacts that have been found from ancient Egyptian and Persian
civilizations as far back as 3,000 B.C. and also in China from dynasties dating as far back
as 600 A.D. have contained the color blue. Sometimes this blue color was found in glass
beads, statues, and porcelain. It wasn't until the mid- I 700's that the blue color was finally
attributed to the element cobalt. |
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This element makes up only about 0.00 1 % of the Earth's surface. It can be found in minute quantities of meteoritic native nickel-iron, soils, plants and animals, combined with other elements in natural waters, and in nodules beneath the oceans. It can even be found in the Sun, cosmic atmospheres, and in some minerals such as, cobaltite, linnaeite, heterogenite, and erythrite. Its two allotropes, a hexagonal structure, which is stable below 417 C (783 F), and a fa6e-centered-cubic, which is stable at very high temperatures, is known to be part of polished cobalt that is silver-white with a faint bluish tinge.
In a compound that has cobalt, cobalt nearly always exhibits a +2 or +3 oxidation state, although other states are known to exist. Compounds where cobalt is divalent are called cobaltous, while trivalent cobalt compounds are called cobaltic. However, if cobalt is finely divided, it will ignite spontaneouly.
The element cobalt has many well known uses both in metals and minerals. One of its uses is that it can be combined with other metals, such as nickel and iron, to make alloys or magnets. Of course when combined with nickel, iron, and other metals, we get Alnico which is used in jet and gas turbine engines. It can be used in electroplating and as a paint pigment. It is also used in magnet steels and stainless steels.
Another use of the element cobalt is in some minerals and in some materials that emit high levels of radioactive energy. One of the mineral uses is that it can be found in Marmite (yeast extract) which happens to be a source of vitamin B 12 which is used in preventing the disease pernicious anemia. It also can be found in the Australian compound Vegemite.
Some of the materials cobalt is used in are highly radioactive and very dangerous. One of these materials happens to be a lethal kind of isotope of cobalt which is cobalt-60. This isotope of cobalt produces Gamma radiation which is being used in place of X-rays or alpha rays from the inspection of industrial machines to the treatment of cancer in hospitals. However, this does not mean it is safe. radiation. The reason it has already been replaced is that cesium 1-3-7 has a long 30 year half-life.
Of course this is probably not the last time we will see cobalt. For in the future someone might invent something that has the element cobalt. Then again, maybe there will be a product that involves the element cobalt.
