A picture once believed to be a copy of a famous Constable painting and valued at £500 has been declared real - and is now up for auction for a guide price of between £2 million and £3 million.
The oil sketch of Salisbury Cathedral was sold in 2013 as a tribute to Constable's work, and was snapped up by a collector for £3,500. But, suspecting that part of the original work had been painted over, the owner called in the restorers - and found the original painting hiding underneath.
It's now been identified as a preparatory sketch for the painting Salisbury Cathedral from the Meadows, which was bought by the Tate gallery last year for £23.1 million.
Before its sale in 2013, the painting had hung for more than a century at Hambleden Manor in the Chilterns. But when Lady Hambleden sold off the contents of the house, including the painting, experts failed to identify its true origin. At some point around a century ago, it seems, it had been heavily overpainted in an attempt to 'finish it off'.
"The recent emergence of this oil sketch from the Hambleden collection, where it was hitherto completely unknown to scholars, reveals its key role in establishing the dramatic and beautiful chiaroscuro of the final picture; the striking light effects on the cathedral in the completed picture, with its majestic spire piercing the stormy sky like a needle, are derived chiefly from the present study," says auctioneer Sotheby's.
"Moreover, it also reveals Constable's development of the composition, notably at the right where the familiar shape of Harnham Ridge now comes into view. It is thus one of the most exciting and important additions to the master's oeuvre to have emerged in recent decades."
The painting will be auctioned by Sotheby's in New York on January 29, with a guide price of between £2 and £3 million.
Sadly, long-lost masterpieces are few and far between - but they do emerge from time to time. In 2013, a painting bought as part of a £30 'job lot' was revealed live on BBC Breakfast to be another Constable, and valued at £250,000.
Around the same time - and even more dramatically - a Van Dyck portrait was identified on the Antiques Road Show and later valued at up to £500,000.
And, last year, a picture bought for £400 was revealed as the long-lost work Lady Mary Wortley Montagu in Turkey by Victorian artist Jerry Barrett, and revalued at £180,000. So you never know, it might be worth getting Granny's old pictures professionally cleaned and discovering what lies underneath.
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