A rare black diamond is displayed at the Natural History Museum

A large naturally black diamond has gone on display in the Natural History Museum’s minerals vault after being loaned to the museum for a year.
All diamonds are coloured by impurities in the crystal, but a pure black diamond is quite unusual as only one in 10,000 natural diamonds is classed as fancy coloured, and out of these, only a handful of them are truly black. In addition to being unusual in colour, at 93 carats, it’s also the largest diamond currently on display at the Museum.