1,109ct Rough Un-Cut Diamond not sold in the Auction.

The world's largest uncut diamond has failed to sell at a London auction after bids did not reach the minimum reserve price.

The Lesedi la Rona, almost the size of a tennis ball, was unearthed in Botswana in November.

The rough diamond is 1,109 carats and believed to be more than 2.5 billion years old.

It had been expected to sell for more than £52m ($70m) but the highest bid was about £45m ($61m).

The auction at Sotheby's was the first time a rough diamond of such a size has gone on public sale.

Ritz Jewelers, Los Angeles

Ritz Jewelers