In 2017, a woman walked into a thrift store in New Hampshire looking for frames to repurpose when a painting stood out.

It portrays two women, one sits in a chair, and the other stands beside her, putting a hand out on the table between them. Priced for only $4 at Savers thrift store in Manchester, New Hampshire, the woman told CNN that, having an uncanny resemblance to the work of American 20th-century painter N.C. Wyeth, she joked about it actually being one of his original pieces.

Unable to find information about the piece online, she hung it up in her home for years, before eventually storing it in a closet, where it remained untouched until this past May, while she was cleaning her home.

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This time, the woman posted a picture of the painting in a Facebook group, “Things Found in Walls,” where users share stories about pieces found in homes or elsewhere.

The painting is only one of four in a collection by the prolific American painter, N.C. Wyeth. Bonhams Skinner.

Comments flooded in, eventually prompting the woman to seek expert help from former curator Lauren Lewis, who had worked with Wyeth’s art for decades. After Lewis saw the painting in person, she was “99 percent” positive it was authentic, the Boston Globe reported.

“While it certainly had some small scratches and it could use a surface clean, it was in remarkable condition considering none of us had any idea of its journey over the last 80 years,” Lewis told the outlet.

After further investigation, the painting was, in fact, confirmed to be not only a Wyeth original but only one of four in a collection the painter did in 1939 for Helen Hunt Jackson’s novel Ramona. According to auctioneer Bonhams Skinner — where the painting will be up for grabs in September — only one other piece in the collection has been recovered.

The woman’s $4 thrift find will be available for auction on September 19th, and Bonhams lists the piece as having estimated starting bids between $150,000 and $250,000.

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