John Constable: Previously unknown sketch by famous The Hay Wain painter discovered in Yorkshire sells for £320,000 at auction

The artwork, which is believed to have been created between 1809 and 1814, is of the countryside that surrounded the artist's childhood home in East Bergholt on the Sussex and Essex border.

Constable, who died aged 60 in 1837, was best known for his oil painting 'The Hay Wain' which won a gold medal at art exhibition the Paris Salon in 1824.

The 12 by 15 inches sketch, called 'Dedham Vale looking towards Langham', has never been recorded but it has emerged from a private family collection in North Yorkshire.

The painting was expected to sell for £150,000 to £200,000 when it went to auction on Saturday - but it instead sold for £320,000.

Jane Tennant, director at Tennants Auctioneers in Leyburn, previously said that Constable had an "extraordinary career" and that he was "an icon of British art history."

She said: "Constable is such an icon of British art history, and we are delighted to be handling the sale of this lively and expressive landscape.

"Oil sketches, much like drawings, have an immediacy - a direct link to the mind and working practices of an artist.

"Executed when he was just starting out on his extraordinary career, he has managed to imbue the sketchily painted landscape with such vitality with his deft handling of dramatic light and shade."