The drawing, in black ink and chalk, had turned out to be a previously unknown work by Carlo Maratta, an important 17th-century master - a preparatory study for his major 1674 altarpiece depicting the Madonna and Child for the Church of Santa Maria in Vallicella, Rome.
Its new home and owner is the Louvre, in Paris.
It was bought for a few pennies more than 40 years ago by the owner's father, thought to have been an amateur artist. Although impressed by the draughtsmanship, he did not appreciate the drawing's importance when he stuck pins into it to hang it up. It remained on the kitchen door until the owner, prompted by a friend, had it valued.
The potential importance of the work was first realised by Richard Allen, a director of Halls Fine Art, the Shrewsbury auctioneer. Mr Allen said: 'What alerted me first was the fact that the drawing was of fine quality and executed on old paper . . . The collection stamp, which proved its provenance . . . made me look a second time.' He said that although it had for years 'boiled away with the sprouts', its condition was 'amazing'.
The Wolverhampton man, who is in hospital undergoing heart surgery, asked not to be named: as 'a man of modest means', he fears losing his council house if found to have suddenly acquired a large sum of money.
The Italian inscription on the back of the drawing's mount describes how the finished altarpiece was 'so renowned for its beauty that everybody comes to see and admire it'.
Cristiana Romalli, Sotheby's Old Master drawings specialist, who gave it an estimate of dollars 25,000 to dollars 35,000, linked the drawing to two similar studies in the Louvre - though this example 'represents a step further in the development of the final composition'.
The National Gallery in London has acquired an important late work by Jacques-Louis David, the French neo-classical artist. Portrait of the Vicomtesse Vilain and her Daughter, 1816, goes on view from today.
A collection of eight original drawings by Beatrix Potter sold for more than pounds 29,430 at Christie's South Kensington.Reuse content