Piles of granny’s pearls and other glittering bequests are lying around at the back of drawers and in dusty boxes, unworn, unloved and unvalued, according to Bonhams, which estimates families to be ignoring assets that are worth life-changing amounts of money.

The London auction house is launching its annual Jewellery in June, during which people are invited to bring in such pieces for a free valuation. ‘A lot of people have no idea just how valuable these pieces could be,’ says Bonhams’ head of jewellery, Jean Ghika, who estimates there to be some £50 million worth of gems stashed away across Britain. ‘We’ve had some astonishing finds, often brought to us in carrier bags or wrapped in tea towels.’

Serendipitous finds include a 1950s floral spray brooch that hadn’t been worn for 20 years and made £27,500 at auction; an Art Deco emerald-and-diamond bracelet that had languished in a bank vault for years and sold for £48,000; a diamond ring found in an evening bag, which made £19,200 and paid a granddaughter’s deposit on a flat; and a diamond necklace kept at the back of a wardrobe and only insured for £4,000, which made £39,650 and paid off a mortgage.

To book an appointment, telephone 020-7468 8278 or email jewellery@bonhams.com

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