However these mining hotspots are not the only places on the Earth where high concentrations of cobalt can be found. The nodules are manganese minerals that take millions of years to form, and there are many tonnes of cobalt present in this form.
So you can see that cobalt is never found alone but always palled up with other transition metals in their ores, mainly copper and nickel. In fact cobalt metal was not isolated and purified until as late as by the Swedish scientist G. Cobalt can also sometimes be found in mixed arsenic ores, and it is cobalt's association with arsenic that gives it its name.
The word cobalt comes from the German "Kobolds" which means goblin or trouble maker. It was so called in this early mining region because it was very difficult to smelt without oxidising and smelting would release the associated arsenic vapours which would lead to pretty troublesome or even deadly processing conditions for the worker.
The Kobolds were blamed and the name stuck. With the exception of the mining region, cobalt is not very abundant, with only trace amounts in the Earths crust about times less than iron. However, it is a metal that is essential for life in the trace amounts. Cobalt is the metal at the centre of vitamin B 12 which helps regulate cell development and therefore DNA and energy production in the body.
Cobalt has been known and used by people for its beautiful colouring and pigment properties as far back as BC. Egyptian cobalt blue paints and Prussian cobalt oxide necklaces have been dated back to this time while cobalt glass has been found in a Greek vase dated at BC.
Cobalt was also used to colour glass in the Chinese Tang dynasty from AD. In fact all the way up until the beginning of the 20 th century people have only really exploited cobalt for its beautiful colour. However cobalt is not just a pretty face. Cobalt is a lustrous very hard silvery metal belonging to a group called the "transition metals".
It is one of only 3 ferromagnetic transition elements along with iron and nickel. As a metal it is very mechanically hard and tough, and it has a very high melting point hence the smelting problems and also remains magnetic to the highest temperature of all the magnetic elements.
When cobalt is combined with other metals its strength allow a range of super alloys to be created. In particular, cobalt's very high melting point and mechanical strength at high temperatures has seen its extensive use in what is termed 'superalloys'.
These are alloys that retain mechanical strength at high temperatures. Because of its impressive properties cobalt is an important component in wear resistant and corrosive resistant alloys. And cobalt alloys and coatings are seen everywhere from drills to saws, from aircraft turbines to prosthetic bone replacements. The fact that cobalt is magnetic has also been exploited with the Japanese invention of cobalt magnetic steel where adding cobalt to steel vastly increases the magnetic hardness.
Just a few years after that in the s saw the pivotal invention of Alnico magnets, which as the name suggests, are composed of aluminium, nickel and cobalt. The fact that cobalt retains its magnetism up to high temperatures is also a very favourable trait when the addition of cobalt to a magnetic material can improve its properties at high temperatures. More recently the creation of rare-earth magnets have given us much stronger, harder, permanent magnets than Alnico magnets.
Because it is magnetically and mechanically hard up to very high temperatures, it has found uses in high-speed motors and turbo machinery. More recently cobalt has a major use in newer batteries, magnetic particles for recording and storage information in magnetic tapes and hard drives. So cobalt; giving joy in an array of beautiful colours, but also ultra strong, hard and magnetic.
Cobalt is never alone, it is found associated with different metals in their ore and has its best mechanical properties when palled up with others. Emphasising the importance, of course, of teamwork. Next week it's the turn of the stuff that amongst other things makes Parker pen nibs write so nicely, but if you haven't heard of it before, then you're probably in good company.
Stop the proverbial "man in the street" and ask him what ruthenium is and the chances are he won't be able to tell you. Compared to the "sexier elements" that are household names like carbon and oxygen, ruthenium is, frankly, a bit obscure. In fact even if your man in the street was wearing a lab coat and walking on a street very close to a university chemistry department he might still be a bit ignorant about this mysterious metal. It wasn't always that way, though. And you can hear how ruthenium rose to prominence with Jonathan Steed on next week's Chemistry in its Element.
I'm Chris Smith, thank you for listening and goodbye. Chemistry in its element is brought to you by the Royal Society of Chemistry and produced by thenakedscientists. There's more information and other episodes of Chemistry in its element on our website at chemistryworld.
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The name is derived from the German word 'kobald', meaning goblin. Melting point. Boiling point. Atomic number. Relative atomic mass. Key isotopes. Electron configuration. CAS number. ChemSpider ID. Looking at the history of cobalt, it's clear that the element has undergone a significant transformation from an "ugly duckling" of no interest to miners into a "swan" of strategic industrial importance.
Atomic mass: History: Minerals containing cobalt were used by the early civilizations of Egypt and Mesopotamia for coloring and dyeing. The element was isolated by Swedish chemist Georg Brandt in Occurrence: Found in the minerals cobaltite, smaltite, and erythrite and is often associated with nickel, silver, lead, copper, and iron ores.
Appearance: Silvery blue, hard, brittle metal. Behavior: Stable in air, unaffected by water, and slowly attacked by dilute acids. It has low toxicity by ingestion but is a suspected carcinogen. Uses: Cobalt is essential to most species, including humans. It is used in alloys for magnets, in ceramics, in catalysts, and in paints.
Cobalt is also used in magnetic and stainless steels. The metal is used in electroplating. Cobalt was discovered by Georg Brandt, a Swedish chemist, in Brandt was attempting to prove that the ability of certain minerals to color glass blue was due to an unknown element and not to bismuth , as was commonly believed at the time.
Cobalt is usually recovered as a byproduct of mining and refining nickel , silver , lead , copper and iron. Although cobalt is used in electroplating to give objects an attractive surface that resists oxidation, it is more widely used to form alloys. Alnico, an alloy consisting of aluminum , nickel and cobalt is used to make powerful permanent magnets. Stellite alloys, which contain cobalt, chromium and tungsten, are used to make high-speed and high temperature cutting tools and dyes.
Cobalt is also used to make alloys for jet engines and gas turbines, magnetic steels and some types of stainless steels.
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