How do you cut diamonds?

Diamonds are hewn from a rough stone to a multi-sided gem so that they reflect light in a beautiful way. Diamonds are extremely hard which makes them difficult to cut. First, a 3D computer model is made of the diamond, so the final shape can be planned out. The gem is then cut up using a diamond saw or a laser. After this, the faces of the stone are ground flat against another diamond and, finally, the faces are polished. The stone is then cleaned in acid to give a brilliant finish.

Answered by David Gelsthorpe, Manchester Museum.