Humphry Davy Proves Diamonds are Made of Carbon

In Florence, while the guest of the Grand Duke, Davy performed an impressive carbon-based experiment which proved that the most apparently precious of objects — the diamond — could also be the product of nature’s simplest processes. With the Duke’s permission, he commandeered the huge solar magnifying lens at the Florentine Cabinet of Natural History, and subjected an uncut diamond to intense and continuous heat. The diamond eventually burst into flame, leaving a fine crust of black carbon, thereby proving, against all the commonsense evidence, that the clear, hard, glittering crystal was really little more than a lump of coal. Both were varieties of carbon, laid down by nature over millennia.

Richard Holmes, The Age of Wonder (2010-03-02)

• carbon
• carbon cycle
• experimentation