As well as holding pride of place as the most sought-after of all precious gemstones, diamond possesses a dazzling array of technologically useful properties. As well as being the hardest, most thermally conducting, and chemically resistant of all known materials it is also biocompatible, highly transparent and of great interest for use in the electronics industry. And now, to top it all off, Evgeni Ekimov and colleagues report in Nature, that under the correct conditions, it can also become a superconductor.