A Roman helmet unearthed in a Cumbrian field by a metal detector enthusiast has sold for £2.3 million - almost eight times the estimated price.
But the colossal price caused disappointment for a Carlisle museum which has spent weeks frantically trying to raise funds to ensure the "exceptional" artefact remains in the UK for public display.
The Crosby Garrett Helmet, named after the village near which it was found, sold for £2,281,250 at Christie's South Kensington.
It was bought by an anonymous bidder and it is unclear what will now happen to the bronze discovery, although it will have made its unnamed finder very wealthy.
The buyer may plan to keep it in a private collection or even apply to take it overseas, although such a move could cause the Government to step in and impose an export bar. This would allow time to try to match price and retain it within the UK.
Six bidders were in the running at the London sale, pushing the price steeply from its original £200,000-£300,000 estimate past the £2 million mark.
The helmet - one of only three such items to be found - is almost 2,000 years old and was bought anonymously.
It was found in May 2010 and is thought to date from the late 1st to 2nd century AD. It would have been used for show in a sporting event rather than protection in combat.
The helmet was billed by experts as "an extraordinary example of Roman metalwork at its zenith".
Thwarted bidders included Tullie House in Carlisle which has been frantically fundraising in the past few weeks to buy the helmet. It had already secured £1 million from the National Heritage Memorial Fund and a further award from the Art Fund.