IN THE marketplaces of planet Earth diamonds are both desirable and scarce, and that makes them expensive. Both the demand and the rarity are, however, largely artificial. Diamonds were made desirable in the 20th century mainly by a marketing campaign from De Beers, a big South African producer of the stones. The scarcity was, until recently, a result of the same company—which at one point controlled about 90% of the world’s production—ensuring that the number of stones which found their way into the world’s jewellery shops was well regulated.
In nature, though, diamonds are unremarkable. They are simply crystals of carbon, albeit crystals of a type that needs a fair amount of pressure to form. And carbon is the fourth-most abundant element in the universe. For that reason, diamonds are thought to be the commonest gemstones on Earth. Elsewhere in the cosmos, as demonstrated in a paper just published in Nature...Continue reading
Source: Science and technology http://ift.tt/2w0WHjg
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