A painting by British artist Joseph Wright (1734-1797) that was dismissed as a fake for many years has been confirmed as his work at the Derby Museum.
Titled Coliseum by the Moonlight, the piece had been poorly restored during the 1960s. It has since been valued at around £1m ($1.4m).
For many years it was believed to be by a follower of Wright, but that view was challeneged after old files were unearthed indicating the painting's existence.
Lucy Bamford, the museum's senior curator of art, told the BBC: "We said 'That can't be. There's one in the store but it's absolutely terrible. Once we got it out...we realised that there was something behind that painting which was worth investigating…
"It's a really interesting insight into Wright's working methods and the way that he thought."
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