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An Amazing find from a 'boot' sale

A large diamond ring purchased for £10 at a car boot sale is expected to fetch £350,000 under the hammer at Sotheby’s July auction.

The ring, which was bought 30 years ago for £10 when the original owner had mistaken it for a piece of costume jewellery, has been described by Sotheby’s as a 26.27ct, cushion-shaped, white diamond stone.

It is said the original owner may have thought it was a CZ due to 19th Century diamonds not being cut to show off their brilliance like today’s gems.

The auction house’s head of London jewellery department Jessica Wyndham told the Press Association: “The owner would wear it out shopping, wear it day-to-day. It’s a good looking ring but it was bought as a costume jewel. No-one had any idea it had any intrinsic value at all. They enjoyed it all this time.”

Wyndham continued: “They’d been to quite a few car boot sales over the years. But they don’t have any history of collecting antiques and they don’t have any history of collecting diamonds. This is a one-off windfall, an amazing find.”

After around 30 years of wearing the ring, the owners bought it into Sotheby’s after a jeweller told them it could have substantial value.

Sotheby’s got the stone tested at the Gemological Institute of America.

The diamond is thought to have been cut in the 19th Century but its history and how it arrived at the car boot sale, is unknown.

“With an old style of cutting, an antique cushion shape, the light doesn’t reflect back as much as it would from a modern stone cutting,” explained Wyndham. “Cutters worked more with the natural shape of the crystal, to conserve as much weight of the crystal rather than make it as brilliant as possible. The older stones have quite a bit of personality, they sparkle in a different way.” The diamond ring will be offered as part of Sotheby London’s Fine Jewels

sale, on July 7.


It has been revealed that the independent jeweller who discovered a ring bought at a car-boot sale was actually a 26ct diamond is L Guess Watchmaker & Jewellers.

The ring in question made headlines yesterday as it was revealed a 26.27ct diamond was bought 30 years ago at a car boot sale for £10, as the original owner believed the piece to be costume jewellery. Sotheby’s is now expected to auction the ring for £350,000 in July.

After a few dubious offers from other people of around £500, the ring’s owners were extremely grateful when L Guess, an independent jeweller from Middlesex, provided them with an honest service

The diamond owners, who were regular customers at L Guess, revealed in a casual conversation that they had a ring they were not too sure about. Store jeweller Mark Guess then offered to take a look for them.

When the customers showed Guess the ring, he told Professional Jeweller is was “one of the most beautiful rings” he had even seen.

“At first I had to check this was not April Fools Day,” Guess explains. “I then then proceeded to explain to the two women what they have in their hands is truly something special.”

Mark Guess then went to check the ring in order to confirm his suspicions. Using a microscope and diamond tester he could confirm it was an old cushion cut diamond.

“They were totally speechless,” he reveals. “This is simply a day we will all never forget. I basically told them what they have is a life changing ring which I estimate to be possibly hundreds of thousands.”

The jeweller then helped them discuss the best course of action, suggesting Sotheby’s as a good auction house. While he told them to think about it, the owners headed to Sotheby’s the next day.

“They are extremely grateful and have invited me along to go with them to the auction.

“This is a proper ‘del boy’ moment we have been joking about since, and in the same auction house too.. the family that own the ring are such lovely people and seriously had had some really bad luck recently, this is something that should hopefully right a few wrongs for them,” concludes Guess.

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