The unsuspecting anonymous woman had been wearing the jewellery for years after having received them as a gift.
But when her husband took them to experts to be valued, it was discovered that one of the gems was an extremely rare natural pearl. It was sent for X-rays and the theory was confirmed.
At 17.4mm, it was the largest natural pearl of its kind to have come up for auction and it was given a pre-sale estimate of £120,000 by experts from Woolley and Wallis Auctioneers.
However, after furious bidding on the pearl, the price soared to over £800,000.
David Morris, international jeweller of London's Bond Street, was the lucky buyer. He plans to turn it into a necklace for a potential buyer in Hong Kong.
Jonathan Edwards, head of the jewellery department at Woolley and Wallis, told the Daily Mail: "It is very difficult to tell if a pearl is cultured or natural by looking at it and you can never be 100 per cent sure unless you have it X-rayed.
"We had it X-rayed at a London lab and they said it was natural, and we then sent it to a lab in Switzerland who said the same thing."
We bet the couple were grateful for his "pearls" of wisdom!
By Joann Khatib
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