Charles Hanson, the manager of Hansons Auctioneers and star of BBC One’s Bargain Hunt, found the painting during a routine home visit in Belper.
He remarked: “It was a thrill to uncover a portrait by a local artist who today is world renowned and some of his paintings can be worth millions.”
The oil on canvas is painted with a half-length portrait of a gentleman who is titled as being John Dawes Mather, (1761-1831). The painting was executed in around 1783.
“The composition of the portrait very much confirms to me it is by Joseph Wright of Derby,” commented Mr Hanson.
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“Furthermore, the provenance for the picture is very good, by family descent it was restored in 1929.”
Born in Derby in 1734, Wright was an English painter, active mainly in Derby and known as ‘Wright of Derby’.
He was one of the most original, versatile, and accomplished British artists of the 18th century and the first major English painter whose career was based outside London.
By the 1750s, Wright of Derby had made his name as a portraitist in the Midlands.
This work displays his fluent composition and a firm grasp of character.
Very little is known about John Dawes Mather, although it is thought he must have been an influential gentleman in Derby and Spondon in the late 18th century.
The picture, which will carry a guide price of between £2,000 and £3,000 in the Hansons Spring Fine Auction on Friday March 31, is expected to generate worldwide interest.
Mr Hanson commented: “I hope the painting stays in Derby and is purchased by a local museum or collector from our county.”
Hansons hold auctions at their modern, purpose-built showroom on Heage Lane in Etwall.
The impressive building comprises a large auction showroom, catering on show and viewing days, and has seating for 150 people and parking for up to 200 cars.
For further details about Hansons and its Spring Fine Arts Auction on March 31, visit their website www.hansonsauctioneers.co.uk.