A 26-carat diamond ring, bought for $13 at a London car boot sale (an outdoor market where people sell personal possessions out of their cars) has been valued at up to $456,000. It is set to be sold on June 7 at a Sotheby's auction.
The owner bought the ring in the 1980s, thinking it was a piece of ordinary costume jewelery.
"This is an extremely rare find," said Jessica Wyndham, head of the auction house's jewelery department. "We're used to people coming in with pieces from their personal collections but this was exceptional."
According to Wyndham, the diamond's sparkle was likely hidden by the darkened ring mount and the old-fashioned style of the jewel's cut.
"When we think of diamonds, we think of modern cuts, of brilliance," Wyndham told CNN. "This wouldn't have looked like that. The silver had tarnished and there was probably some dirt. These diamonds were made for candlelight, not our white artificial light, so it was all about trying to bring out its fire."
The earliest known stone copy of the Ten Commandments sold at auction in Beverly Hills in 2016 for $850,000. Credit: Heritage Auctions
After decades of wearing the ornament, the owner, who has chosen to remain anonymous, decided to have the ring valued at a local jeweler's, where it was suggested that the ring might be set with a genuine diamond. Eventually it was revealed that the jewel was a cushion-shaped diamond, set in a 19th-century mount.
The ring is now expected to fetch between $325,000 to $456,000 at auction