The Disguises of Carbon

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Did you know that a brilliant sparkling diamond is exactly the same substance as dull, black graphite? Despite the difference in price between diamonds and pencil lead, both are forms of carbon. This element has such special properties that all the molecules in your body are built from it.

Graphite and diamond, though the same, could hardly be more different. Graphite is dark, opaque and soft which makes it useful as the so-called "lead" in pencils. Transparent diamond is the world’s hardest naturally-occurring substance and is used in cutting tools as well as jewellery.

The enormous difference between diamond and graphite occurs arises from the different ways that the carbon atoms are arranged. In graphite, the carbon atoms are in hexagonal layers, which slide over each other, making it an excellent lubricant. The carbon in diamond has been subjected to high temperatures and pressures deep beneath the earth’s crust. This changes the arrangement of carbon atoms to the tetrahedral one found in diamond where every carbon atom is joined to every other carbon atom.

In 1985, scientists discovered yet another form of carbon, they called "buckyball." In this form, the carbon atoms are arranged like the pattern on a soccer ball. Buckyballs are found in space dust and have many unusual properties.

So next time you use a pencil remember that those same carbon atoms could have been part of a glittering gem worth thousands of dollars.