Following two years of painstaking detective work, a Yorkshire family has succeeded in proving the attribution of a Victorian painting - and seen its value rise by 20 times as a result.
The Sutcliffe family, which owns a gallery in Harrogate, bought the painting, which depicts an English lady being dressed by two servants in Turkey (left), for £9,000. Christie's had previously described it as being by an unknown student or imitator of John Callcot Horsley, the designer of the first ever Christmas card, and thus not particularly valuable.
But the family had other ideas. And after two years of research, they were finally able to prove that the painting is the long-lost work Lady Mary Wortley Montagu in Turkey by Jerry Barrett, best-known for his painting of Florence Nightingale aiding the wounded during the Crimean War.
The key to the discovery was the shoe worn by the maid on the right-hand-side of the picture. The Sutcliffes spotted a close similarity with a shoe in another of Barrett's paintings, Sheridan Assisting Miss Linley on her Flight from Bath.
The painting is now to go under the hammer tomorrow at the BADA Antiques & Fine Art Fair in Chelsea - where it's expected to make as much as £180,000.
It's not all that unusual for lost masterpieces to re-emerge. In a case that received widespread attention last year, a painting by Anthony van Dyck was discovered on the Antiques Roadshow - after presenter Fiona Bruce said she "had a hunch" that it might be genuine. Bought for £400, it's now believed to be worth a thousand times as much.
So what should you do if you suspect that that grubby old picture of granny's might be worth real money?
"If someone thinks they have something that may be of value, the best thing to do is to go to a reputable art dealer," says a spokesperson for the BADA Antiques & Fine Art Fair.
"The painting may have a date, in which case they should look for a dealer specialising in that period - there's information on the BADA website - and send them a .JPEG. That's much better than taking it to a country fair, because you never know whether there will be somebody there that will actually recognise it."