The line-up of headlining names involved in Gem Diamonds, led by South African founder and chief Clifford Elphick , friend of the Oppenheimers, was joined last week by Laurence Graff , owner of Graff Diamonds, when he bought a 4.5 per cent stake.

He said at the time the shares were a long-term investment, probably no bad thing after their 40 per cent slide yesterday.