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E very weekend morning through spring and summer, scores of people arrive in car parks, school playgrounds and sports fields to lay out tables of pre-loved wares for keen, eagle-eyed collectors. In 2019, an estimated 45,000 car boot sales (aka flea markets) happen each year, with 13 million shoppers making purchases.
They are the epitome of “one person’s trash is another person’s treasure” where you can find anything from vintage clothing and furniture to classic 80s children's toys and pristine unused sports equipment. Any given sale is packed with miscellaneous ornaments, creaking armoires, dusty fur stoles, and other antiques handed down through families.
Occasionally, you might even discover an actual treasure... whether you realize it or not.
In the late 80s, this is exactly what happened to one woman browsing through a car boot sale in Isleworth, West London. Spotting some interesting bangles in a box of costume jewels, she paid no attention to a cocktail ring made up of a single clear stone. It might have been a gobstopper of a gem but it didn't sparkle like one: sitting in a rusty, old setting, it looked dull and filthy – certainly nothing special. The seller was offloading the lot for £12—our heroine haggled her down to £10. The bangles— and the ring—went home with her.
It was only in 2017, thirty years after that unremarkable car boot sale, that the owner thought to have the ring appraised. Over the years, she had worn it as one might wear a cocktail ring—regularly—thinking that it couldn't possibly be worth anything.
And so, without particularly high hopes, she took it along to a local jeweler who immediately knew that he was looking at something special. He suspected it was a real diamond, but it was too big for him to measure the carats accurately. The owner followed up by calling Sotheby’s to arrange an appointment.
"The first time I saw the diamond in person it was clear that it was a special stone." says Jessica Wyndham, Head of High Jewelry in Europe for Sotheby's. "It possessed a charm that only older diamond cuts can offer, with a softer, more luminous glow, giving it its own unique appeal."
The "Tenner" ring ultimately sold for £656,750.
The Sotheby's team sent the piece to the Gemological Institute of America for evaluation. It came back with quite the report: the cushion-cut diamond is enormous, weighing in at 26.27 carats, bears a color grade of I and an impressive clarity grade of VVS2. Once Sotheby’s had the diamond confirmed as genuine, the story of the car boot sale find—suitably nicknamed the “Tenner” diamond—went viral, making international headlines. When it entered the Fine Jewels Sale in June 2017, the high estimate was listed as £350,000.
After some frenzied bidding, the stone ultimately sold for £656,750, a life-changing sum for the owner.
But how could such a stunning diamond end up amongst trinkets on a car boot sale table? We'll never know the full story, but the specialists at Sotheby’s have posited a few theories.
"It's one of those wonderful stories that almost seems too improbable to be true." says Wyndham. "Most people simply wouldn't imagine that they could be carrying around a diamond of this size and importance, particularly if it had long been thought of as a piece of costume jewelry. If you've always believed something isn't valuable, there's little reason to question it."
The seller wore the ring for years with nary a raised eyebrow.
Wyndham finds it even more remarkable that the seller wore the ring for years with nary a raised eyebrow from anyone she encountered. No one else seemed to recognize the diamond's significance, either.
It's possible as well, that the cut of the diamond was less familiar to a modern eye. "These older cushion-cut diamonds have a wonderful charm and character," says Wyndham. "Unlike modern diamonds, which are cut to maximize brilliance and return of light, older diamonds were fashioned to display their "fire," which is the splitting of the light into its spectral colors. It would have looked magnificent in the candlelight of the time."
Luckily, this kind of cut has returned to favor according to Wyndham. "These older cuts have a very different personality from contemporary cuts. The proportions give a distinctive light performance which lead to a charming quality which collectors find especially appealing today."
Additionally, the mount was unusual in a modern context. Composed of a blend of silver and gold (common in the late 19th century which is when we believe it was made), it tarnished over time, becoming darker and duller than mounts we typically see today. "It's worth remembering that the ring would have looked quite different when it was first made. It would originally have had a much brighter appearance, enhancing the overall brilliance of the jewel."
This is far from the only diamond that has made it's way to Sotheby's via a long and winding road. "Over the years, we have handled jewels found hidden in old curtains, tucked into chair upholstery, or uncovered beneath floorboards in forgotten garages," says Wyndham. "What makes this diamond so remarkable is the combination of its size, quality and the extraordinary circumstances of its purchase and later discovery."
If you, having read this story, are inspired to rummage around in Grandma's old jewelry box or digging between the couch cushions, Wyndham suggests looking for signatures in the mounts or stamps on the jewels themselves which are the clearest indications of when something might have been made, who made it, and the level of quality. When in doubt, Sotheby's is available to assist: every jewelry specialist is a gemologist and will be able to identify the key characteristics of gemstones.
There are still important treasures waiting to be uncovered...hopefully that next great find is closer than we might imagine."
The “Tenner” diamond’s seller remains a regular attendee at car boot sales, knowing better than anyone that treasures may be hidden in the unlikeliest of places. "Stories like this are also a reminder that there are still important treasures waiting to be uncovered! While discoveries of this caliber are exceptional, hopefully that next great find is closer than we might imagine."
