A diamond ring bought a car boot sale for just £10 has been sold at auction for a whopping £656,750.
The cushion-shaped jewel had been expected to fetch up to £350,000 when it went under the hammer at Sotheby's in London.
But in the end it was snapped up for close to twice that amount.
Named the 'Tenner' diamond, the ring was originally purchased in the 1980s from a car boot sale.
The 26.27 carat diamond is thought to have been cut in the 19th Century but its full history is unknown.
The previous woman owner spotted the ring in the 1980s and assumed it was a decorative costume jewel.
She wore it regularly, carrying out mundane daily chores and earlier this year decided it was time to have it valued.
It was recently confirmed by the Gemological Institute of America (GIA) as a genuine diamond.
Another highlight of the Sotheby's sale was a Cartier diamond brooch worn by Margaret Thatcher on a number of high-profile public occasions, including the day she offered her resignation as Prime Minister to the Queen.
With its geometric chevron design, the brooch piqued the interest of buyers to achieve £81,250.
It had been estimated that it would fetch from £25,000 to £35,000.
Proceeds from that sale will be donated to the Endeavour Fund - a charity that supports the recovery of wounded, injured and sick servicemen and women.
Jessica Wyndham, Sotheby's head of the London jewellery department, said: "It was a thrill to bring the hammer down on two objects which have been the subject of so much interest and attention over the last few weeks and to see that attention translate into such strong bidding competition."