A 25.59-carat "pigeon blood" ruby sold for a world record $30.33 million at auction in Geneva on Tuesday, while a rare pink diamond believed to have once belonged to Napoleon's niece fetched $15.9 million, Sotheby's said.

After competitive bidding, the ruby went to an anonymous telephone bidder for 26.25 million Swiss francs ($28.27 million), with costs.

The "Sunrise Ruby" from Myanmar, part of a collection of Cartier jewels up for auction, had been expected to sell for between $12 million and $18 million. It set a record for a ruby and was also a record for a Cartier jewel at auction, Sotheby's said.