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Cobalt is a chemical element; it has symbol Co and atomic number 27. As with nickel, cobalt is found in the Earth's crust only in a chemically combined form, save for small deposits found in alloys of natural meteoric iron. The free element, produced by reductive smelting, is a hard, lustrous, somewhat brittle, gray metal.
In humans most cobalt is found in Vitamin B12.A cobalt atom is visible in the center in this diagram. Cobalt is essential to the metabolism of all animals.It is a key constituent of cobalamin, also known as vitamin B 12, the primary biological reservoir of cobalt as an ultratrace element.
The compounds cobalt silicate and cobalt(II) aluminate (CoAl 2 O 4, cobalt blue) give a distinctive deep blue color to glass, ceramics, inks, paints and varnishes. Cobalt occurs naturally as only one stable isotope, cobalt-59. Cobalt-60 is a commercially important radioisotope, used as a radioactive tracer and for the production of high-energy ...
[5] [6] Various amalgams of silver and mercury or other metals and mercury do occur rarely as minerals in nature. An example is the mineral eugenite (Ag 11 Hg 2) and related forms. [7] Silver nuggets, wires, and grains are relatively common, but there are also a large number of silver compound minerals owing to silver being more reactive than gold.
Present in most animals, possibly beneficial to plant growth, but not known to be essential; some plants are hyperaccumulators. [11] Common in medical implants. [11] The common compounds are nontoxic. [11] tungsten: 74: 4a: Is a (presumably essential) component of a few bacterial enzymes, and is the heaviest biologically essential element. [67]
Heterogenite is a natural tri-valent cobalt oxyhydroxide mineral. [2] It is the most abundant oxidised cobalt mineral in the Katanga Copperbelt, a region in the Democratic Republic of the Congo. [3] About 70% of known heterogenite is located in the DRC. [4]
Its name stems from the contained element cobalt, whose name is attributed to the German term Kobold, referring to an "underground spirit" or "goblin". The notion of "bewitched" minerals stems from cobaltite and other cobalt ores withstanding the smelting methods of the medieval period, often producing foul-smelling, poisonous fumes in the process.
He was able to show that cobalt was the source of the blue color in glass, which previously had been attributed to the bismuth found with cobalt. He died on 29 April 1768 of prostate cancer. [citation needed] About 1741 he wrote: "As there are six kinds of metals, so I have also shown with reliable experiments...