An old painting found in the kitchen of an elderly woman in France earlier this year — which was determined to be a work of art from a 13th-century artist — made her a multimillionaire on Sunday.

The work, a masterpiece titled “Christ Mocked” and attributed to the Italian painter Cimabue, sold for $26.6 million (24 million euros) to an anonymous buyer near Chantilly, north of Paris, reportedly making it the most expensive medieval painting ever sold.

The expected sale price of the unsigned work, measuring about 10 inches by 8 inches, had been between $4.4 million to $6.6 million.

In June, an auctioneer discovered the painting hanging on a wall while inspecting the woman’s house in Compiegne, which is in northern France, and recommended that she bring it to experts to be evaluated. The painting hadn’t attracted much attention from the woman, who is in her 90s, or her family, who thought it was an old icon from Russia, according to The Guardian.

Acteon Auction House, which sold the masterpiece to the anonymous buyer, said the woman will receive “the majority” of the sale money.

Dominique Le Coent of Acteon Auction House said the sale represented a “world record for a primitive, or a pre-1500 work.”

“It’s a painting that was unique, splendid and monumental. Cimabue was the father of the Renaissance, but this sale goes beyond all our dreams,” Le Coent said.

Art experts said the painting likely was part of a larger diptych that Cimabue painted around 1280; two other panels were displayed at the Frick Collection in New York and the National Gallery in London. The experts at Turquin in Paris reportedly used infrared reflectography to confirm that the piece was part of the diptych containing eight scenes of the passion and crucifixion of Christ.

Cimabue, who was said to have taught Italian master Giotto, broke from the Byzantine style, popular in the Middle Ages, and started including elements of movement and perspective that came to characterize Western painting. Only 11 works painted on wood, none of them signed, have been attributed to Cimabue, as The Guardian reported.

The painting had hung on the kitchen wall of the woman’s home for so long that she reportedly told the auction house she could not remember how she got it.