Doubts grow over record 'diamond' An expert called to test a South African "diamond" claimed to be the world's largest has cast doubt on the alleged find.
Ernest Blom, president of the World Federation of Diamond Bourses, said he was withdrawing completely from the process to verify the stone.
Mr Blom said his requests to see the stone had not been met.
A small mining company said it had dug up the huge gem in South Africa's north-west province last month.
“ I suspect something is afoot ” Ernest Blom, World Federation of Diamond Bourses
A shareholder at the mine had said the green-tinged gem weighed 7,000 carats.
That would have made it more than twice the size of the Cullinan Diamond, the centre-piece of the British crown jewels.
But Mr Blom has distanced himself from the case.
"I am of the opinion that the 'diamond' could exist but I suspect something is afoot," he said.
Mr Blom said he was also told by a journalist that she had been shown a "replica" of the stone that had been passed off as the claimed record diamond.
There was scepticism about the "diamond" from the beginning.
Experts said the north-west province was not known for producing gems and greenish stones were even rarer.
They also said the light-green stone may turn out to be a fluorite crystal.
Story from BBC NEWS:http://news.bbc.co.uk/go/pr/fr/-/2/hi/africa/7036286.stmPublished: 2007/10/09 17:54:44 GMT© BBC MMIX