Thenard was charged with finding an alternative. So, where to begin? Thenard began to think about stained glass windows and ancient pieces of tile and porcelain that been colored blue with rough amalgamations from cobalt ores since antiquity. Clair says. Thenard took a closer look. In , he mixed cobalt phosphate or cobalt arsenate with alumina, then roasted it at a high temperature.
The new pigment took off. In , the artist and art dealer Han van Meegeren found himself in an unusual position. When the Allied art commision began to return paintings to their rightful owners after the war, they discovered that van Meegeren sold an early work of Vermeer to a Nazi official, netting a hefty sum—and collaborating with the Nazi regime, writes St. Clair in The Secret Lives of Color. Van Meegeren had painted it himself. Van Meegeren was a master forger.
In traditional oil paints , pigments are suspended in linseed oil to dry. Van Meegeren used a substance similar to Bakelite instead, which hardened under heat—and also helped him fool X-ray machines and other solvency tests used to date oil paintings, writes St. Relative supply risk An integrated supply risk index from 1 very low risk to 10 very high risk.
Recycling rate The percentage of a commodity which is recycled. Substitutability The availability of suitable substitutes for a given commodity. Reserve distribution The percentage of the world reserves located in the country with the largest reserves. Political stability of top producer A percentile rank for the political stability of the top producing country, derived from World Bank governance indicators. Political stability of top reserve holder A percentile rank for the political stability of the country with the largest reserves, derived from World Bank governance indicators.
Supply risk. Relative supply risk 7. Young's modulus A measure of the stiffness of a substance. Shear modulus A measure of how difficult it is to deform a material.
Bulk modulus A measure of how difficult it is to compress a substance. Vapour pressure A measure of the propensity of a substance to evaporate. Pressure and temperature data — advanced. Listen to Cobalt Podcast Transcript :. You're listening to Chemistry in its element brought to you by Chemistry World , the magazine of the Royal Society of Chemistry.
Hello - beauty, blue glass, B12 and the best magnets that money can buy. So why is this week's element named after a goblin? I always find the question 'what's your favourite element' a difficult one. There are several front runners for vastly varying reasons; however, always a top contender has to be cobalt because it excels in several important character traits: Cobalt has amazing beauty and strength, as well as great cooperation.
All together a highly useful metal. Before I even thought about the chemistry of colour I developed a love for blue glass, something I still collect to this day. Only after studying the transition metal chemistry did I realise that this beautiful blue colour comes from cobalt. Cobalt chloride in fact. However, as far as colours go, cobalt has a few more strings to its bow than just this wonderful blue. Cobalt can also colour glass green, while the hydrated form of cobalt chloride is a beautiful deep rose colour.
As you can imagine this colour change due to the presence of water is highly useful, warranting cobalt chloride an ideal moisture indicator. The array of beautiful colours that cobalt produces were never more prevalent to me than when I went to the cobalt mining region called the Copperbelt in Zambia. In this area the huge multicoloured cobalt minerals deposits tower high, with the shores of dams and streams coloured deep rose with silvery blue veins running through.
Cobalt it is not found pure in Nature but found in sulphur minerals and usually associated with other transition metals. As you can probably guess from the name of the region in Zambia - the Copperbelt, cobalt is mined as a secondary product to copper that is dominant in the ore of this region. Because of this cobalt is normally recovered from the waste of the primary metal extraction. 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.
Click here to view videos about Cobalt. View videos about. Help Text. Learn Chemistry : Your single route to hundreds of free-to-access chemistry teaching resources. We hope that you enjoy your visit to this Site. We welcome your feedback. Data W. Haynes, ed. Version 1. Coursey, D. Schwab, J. Tsai, and R. Cobalt is also used to make alloys for jet engines and gas turbines, magnetic steels and some types of stainless steels. Cobalt, a radioactive isotope of cobalt, is an important source of gamma rays and is used to treat some forms of cancer and as a medical tracer.
Cobalt has a half-life of 5. Cobalt compounds have been used for centuries to color porcelain, glass, pottery, tile and enamel. Some of these compounds are known as: cobalt blue, ceruleum, new blue, smalt, cobalt yellow and cobalt green. In addition to being used as a dye, cobalt is also important to human nutrition as it is an essential part of vitamin B Estimated Crustal Abundance : 2.
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