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What the name means: Chromium comes from the Greek word khroma (or chroma) meaning colour.
Who identified chromium?: In 1761 a German geologist called Johann Gottlob Lehmann, while working in gold mines in the Ural Mountains of Siberia, made observations on a mineral that he believed was a form of red lead. The mineral became known as Siberian red lead. Lehmann's work was short lived (he died in a chemical explosion in 1767) but before the accident he did communicate his observations to Georges-Louis Leclerc, Comte de Buffon, which is why we know about Lehmann's part in the story.
The mineral that Lehmann studied was not, in fact, red lead, Siberian or otherwise, but an ore called crocoite, that contains a compound made from lead, chromium and oxygen. In 1770 a German biologist, Peter Simon Pallas, while on an expedition to the Ural Mountains, discovered the value of crocoite ore in providing pigments for paints. The bright yellow colour it gave to paint became extremely fashionable.
In 1797, Nicolas-Louis Vauquelin, while working for the Comte de Fourcroy, was successful in isolating the new element from crocoite. At the suggestion of the Comte de Fourcroy and the mineralologist René Just Haüy, he called the new element chromium on account of the many different colours it produced when it reacted with various chemicals.
STP = standard temperature and pressure.
About chromium: Chromium is a hard, silvery looking metal. It is mostly mined as chromite, a compound of chromium and oxygen with iron and magnesium. Free chromium is rare in nature but it can be found in certain mines in Russia, particularly where there are diamonds.
Chromium metal is mostly used mixed with other metals to form alloys. Since it is a hard metal it can help strengthen other metals. It is also necessary in trace amounts in the human body where, as the Cr3+ ion, it is essential for insulin to function correctly in regulating the body's sugar levels.
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