Le Coent said experts were off the mark because it was the first time a Cimabue had ever gone under the hammer.
An auctioneer spotted the painting while inspecting the woman’s house in Compiegne in northern France and suggested she bring it to experts for an evaluation. It hung on a wall between the kitchen and dining room and its owner had considered it an icon of little importance.
Titled Christ Mocked, the painting measures about 24 by 20 centimetres.
Art experts say it is likely part of a larger diptych that Cimabue painted around 1280, of which two other panels are displayed at the Frick Collection in New York and the National Gallery in London.
The painting’s discovery has sent ripples of excitement through the art world.
Cimabue, who taught Italian master Giotto, is widely considered the forefather of the Italian Renaissance. He broke from the Byzantine style popular in the Middle Ages and began to incorporate elements of movement and perspective that came to characterise Western painting.
Specialists at the Turquin gallery in Paris initially examined the painting and concluded that it bore the hallmarks of Cimabue.
Stephane Pinta, an art specialist with the Turquin, pointed to likenesses in facial expressions and buildings, as well as the painter’s techniques for conveying light and distance.