With the world record sale of a purple diamond for $29.3M, it seemed the right time to chat to our diamond expert, Professor Neil Manson, about what a diamond actually is, and how one determines if they are “pure” and “flawless”.

Not surprisingly, the media hype doesn’t match with the actual physics. Professor Manson points out that the colour means the diamond is not pure, and divulges the secret to making diamonds purple, which he does on a regular basis.

The purple colour comes from a combination of two things in the regular lattice of carbon atoms: a gap (or vacancy) and a rogue nitrogen (N) atom, something Professor Manson has become so adept at creating and studying that he is known as Mr NV.

So why study jewellery so intensively? It’s not for commercial gain, but because they show remarkable promise for quantum technology.

NV centres are prime candidates for qubits, quantum sensors and quantum simulators, with the huge advantage that they operate at room temperature, and don’t need the extreme cooling that most of the competition need.

Watch the video to find out more.