Art historians claim to have unearthed a masterpiece by Cimabue, the Florentine painter dubbed "the father of the Renaissance", in an elderly lady’s kitchen at her home near Paris.
Christ Mocked, a tempera painting on a wood panel by the 13th-century artist, is estimated to be worth between €4-6 million (£3.5-5.3m), according to the Old Masters specialists Turquin.
They said the work depicting the Christ’s passion was owned by an old lady in the northern French town of Compiegne, who had it hanging between her kitchen and her sitting room.
It was directly above a hotplate for cooking food. It is not known how the unnamed woman, who is in a home and under legal guardianship, came into possession of the work, which she thought was just a rather old religious icon.
Dominique Le Coënt-de Beaulieu, head of the Actéon auction house, said a judge had called his colleague to empty her house in June after the woman was put in an old people’s home.
“Nothing suggested such a discovery was on the cards as the painting was found among other objects without interest," he told the Telegraph.
It is unclear whether the work has been made available to other Renaissance experts to check its veracity.
The auction house, however, called the finding of the tempera on a gold leaf ground on a poplar panel “a major discovery for the history of Western art” given the rarity of works by Cimabue, who tutored Duccio and Giotto.
The painting is believed to be part of a large diptych dating from 1280 when Cimabue painted eight scenes depicting Christ’s passion and crucifixion.
Historians only recognise a dozen works on panel as being unequivocally by his hand, although none of them are signed. Several Cimabues have been lost in wars, floods and earthquakes.
Mr Le Coënt-de Beaulieu said his colleague had realised there was something special about the work given the emotion of the face of Christ compared to other known Byzantine art figures, which pre-dated the work.
"Cimabue was the first to represent such figures in the terrestrial world with such feelings. The emotion is palpable," he said. It took another couple of months for Turquin to confirm its provenance.
Two other scenes from the work hang in the National Gallery in London — The Virgin and Child with Two Angels – and the Frick Collection in New York (The Flagellation of Christ).
The scene in the National Gallery was also lost for centuries, and only found when a British aristocrat was clearing his ancestral seat in Suffolk.
It was given to the nation in 2000 after a Sotheby’s expert had spotted it in a routine valuation of the contents of Benacre Hall in Suffolk.
That work survived a major fire in the 1920s, when it was among piles of furniture and books dragged by the servants out of the burning house and heaped up on the lawn.
The family believes it may been bought by Sir Edward Sherlock Booth in Florence in the 19th century.
Regarding this latest shock discovery, tests using infrared light meant that there was "no disputing that the painting was done by the same hand" as other known works by Cimabue, said art expert Eric Turquin.
To counter any doubters who may argue it is a strange coincidence that Mr Turquin came across two masterpieces by chance in France in the past five years, Mr Le Coënt-de Beaulieu said there was further proof of provenance: the work was formerly attached to the one hanging in the National Gallery before being cut apart by a French collector. A woodworm trail between the two works fits "like a puzzle", he said.
“Traces of the original framing, the small round dots made with the same sort of stamp, the style, the gold ornamentation, the corresponding of the backs of each of the panels and their similar condition confirm that these panels made up the left side of the same diptych," said his auction house in a statement.
It added: "Notwithstanding a few minimal spots of retouching in the eyes of Christ, one lock of his hair and repainting in the long stick that is hitting his head, the paint surface is in excellent general condition in spite of the heavy dirt that has accumulated over time.”
Analysis also revealed an “underlying drawing”, it said. The work will go under the hammer at Actéon in Senlis, north of Paris, on October 27. The proceeds will go to the woman. It is not known whether she has heirs.