KING’S PLATE IN A TESCO BAG

IT HAD been dropped, propped up on a sideboard and ignored for years. Then in 2010, when her husband was taking some books to be valued by the roadshow in Aberglasney, Carmarthenshire, Wendy Jones grabbed the dusty oval plate, wrapped it in a Tesco carrier bag and slung it on the back seat of the car.

Expert John Axford instantly recognised it as part of an 18th-century royal dinner service specially commissioned for Frederick the Great of Prussia and valued it at £100,000.

Mrs Jones, 68, was staggered. ‘We had no idea it was worth anything,’ she said. ‘I’m speechless. Tesco bags can split!’

Good thing it didn’t. Not least because the 22in plate, made from hard paste porcelain and decorated with the arms of the Hohenzollern family, the order of the Black Eagle and the Maltese Cross, actually belonged to her son, Michael.