Mystery surrounds the identities of the brother and sister who sold a rare Chinese vase they found in their parents' loft for €50m.
The pair were clearing out their parents' house in Pinner, Middlesex, after the elderly couple's death, when they found the vase.
They put it aside, on top of a bookcase, as they continued to deal with the rest of their parents' property.
It was only later that they decided it might be worth something and decided to to put it up for auction.
They took it to the local auctioneer Bainbridges, in nearby Ruislip, who were in turn excited by the find and valued it at between £800,000 (€940,000) and £1.2m (€1.4m).
However, no one expected the reaction from Chinese buyers, who pushed the bidding up over 30 frenzied minutes to a world record £43m (€50m).
By the end of the auction, the price was increasing in £1m chunks as the final few bidders - understood to be mainland Chinese businessmen - vied for the vase.
At one point, the sister selling it almost passed out from the rising value and had to leave the room for some fresh air.
The 18th century Qianlong-dynasty porcelain piece is believed to have fetched the highest price for any Chinese artwork ever sold at auction.
The total price, including commission and VAT on the commission, was £53,105,000.
Helen Porter, of auctioneers Bainbridges, said: "The brother and sister had no idea what they had. They were hopeful but they didn't dare believe until the hammer went down.
The sellers might have asked to remain anonymous and few in the community north west of London appeared to have heard who they were.
However, it might be difficult to keep their new-found wealth a secret.
How the vase came to be in the family in the first place also remains a mystery, although it is understood to have come into its possession in the 1930s.
In the buildup to the sale, Bainbridges described their excitement, before knowing how the sale would develop.
Their online updates noted: "I can’t easily explain the excitement that is building up here in Ruislip.
"In the normal course of our business and from a local house clearance we have received generous instructions to offer what must be one of the most important Chinese vases to be offered for sale this century.
"The vase is of yang cai decoration and reticulated double walled construction. That is to say, there is an inner vase that can be viewed through the perforations of the main body.
"It is of the Qianlong period, circa 1740s. It is 16? high and the ovoid body is decorated with 4 circular cartouches each masterfully carved and enamelled with humorous fish, all beneath a primrose yellow trumpet neck exquisitely painted.
"It is a masterpiece."
Chris Albury, of auctioneers Dominic Winter, based in Swindon, Wilts, said the high price reflected the increased buying power in China.
He said: "It's a freak price. I'm absolutely astonished. What a great find.
"The word would have been going around that this had come up for sale and there have been strong signs of money in China for a few years now.
"This year it's been more noticeable, there have been indications that people have lots of money to spend, but nothing like this."