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Pictured: The coin depicts the king of England from 1135 to 1154 and his wife Matilda, the countess of Boulogne.
An extremely rare 12th century silver penny is tipped to sell for £10,000 after being discovered in a ploughed field by a metal detectorist.
Graeme Rushton, 50, from South Cumbria, was detecting at a site on the South Yorkshire/Lincolnshire border when he got a signal.
After digging down about 6ins he uncovered the Stephen and Matilda penny, depicting the king of England from 1135 to 1154 and his wife Matilda, the countess of Boulogne.
At first Graeme, who owns a metal detecting shop, did not recognise the coin, so he took it home with him for safekeeping. It was only a year later when he decided to contact the Fitzwilliam Museum in Cambridge about it that he became aware of the significance of his discovery.
Graeme is now selling the coin, which is thought to be one of only 25 in existence, with London-based auctioneers Dix Noonan Webb.