London (June 6, 2002)- A purple diamond believed to be the only one of its kind and to have originated in the Amazon basin has come to light in London, according to British press reports.

The Supreme Purple Star - as it is being called - is a deep purple, turning to crimson when rotated in the light.

Lawyers acting for the unnamed owner took it to a London diamond expert, JD Boles, who told journalists the stone was weight-for-weight the most valuable object in the world.

There is some mystery about the diamond - its exact size, ownership and precise origins are unknown, although it is reported to have been cut in the Amazon region about 25 years ago.

The Daily Telegraph put a value of £14 million (about R213 million) on the stone, but the Daily Mail said Boles declined to put a value on it.

The jeweller was so concerned about security he refused to provide his first name.

'No one knew they existed'

Although 10 crimson diamonds are known to exist in the world, no deep purple diamond has been seen before.

"I had never seen or heard anything about stones of this shade existing. It is the first time anyone has found a deep purple diamond, and no one knew they existed before... This is the rarest diamond in the world," said Boles.

He declined to reveal its weight, beyond saying it was between two and five carats. He said he had named it the Supreme Purple Star.

Boles said the gem had been returned to the lawyers and he did not know its whereabouts.

"This stone needs independent verification. There is a question mark about the colour," he said.

Boles believes the owner aims to sell the gem.