A United States woman will soon be $US100,000 richer after she unwittingly bought a Renoir masterpiece at a flea market.
The unnamed woman bought a box of random items, including the painting, for $US50 in Virginia.
Her mother later convinced her to take the painting to a local auction house after noticing Pierre August Renoir's faded signature on the back, the ABC reports.
The director of the Potomac auction house, Ann Cramer, says an art critic took one look at the painting and knew it was the work of the French master.
"Straight away it just looked right," she said.
"I mean it's the colour, it's the vibrant colour, it's the pinks and the purples. Renoir is known for his rapid brush strokes. And colour is really important with Renoir."
Ms Craner believes the painting is a lost treasure. The river scene with vibrant purples and pinks from about 1879 has not been seen for almost a century.
But when the woman first snapped up the box, it was a doll and a plastic cow that caught her eye.
She stuffed the painting into a white rubbish bag and moved from place to place, even being tempted to throw it out.
The painting will go under the hammer on 29 September.
