The largest sapphire ever to be presented for auction has been sold in Switzerland to an anonymous buyer, the BBC reports.

The 478-ct. jewel was reportedly bought by a telephone bidder for almost $1.5 million at an auction in Geneva on Wednesday.

The gem was first recorded in Sri Lanka in 1913 and its previous owners include the royal family of Romania as well as an American jeweler.

The gem is said to be larger than a hen’s egg and only two larger sapphires have been recorded, both in museums.

However the item that reportedly raised the highest price of the evening was an oval-cut diamond, which sold for more than $4 million.

The sale generated a total of more than $25m – the best result in a decade, said Christie’s chairman for Europe, Francois Curiel.

“I think this is because the world economy is becoming stronger and stronger,” he told AFP news agency.

JCK