A woman bought a painting for $4 from a thrift store. Turns out, the art could be worth $250,000 — and experts have 'no idea' how it got there.

• A woman bought a painting for $4 while frame shopping at a New Hampshire thrift store.
• Turns out, the piece from American artist Newell Convers Wyeth could be worth up to $250,000.

A woman's $4 thrift-store find could lead to her getting a hefty paycheck in the near future.

The anonymous thrifter found a painting depicting two women while she was shopping for frames at a Savers thrift store in Manchester, New Hampshire, in 2017, auction house Bonhams Skinner told Insider.

That painting — which the woman bought for $4 — is actually a long-lost piece of art from famed American artist Newell Convers Wyeth and could now fetch up to $250,000 at auction.

The woman bought it for $4 and hung it in her bedroom for a few years, Bonhams Skinner said, before she took it down and stored it in her closet.

But while cleaning earlier this year, the thrifter rediscovered the painting and posted photos of it to a Facebook page called "Things Found in Walls," a private group with 562,000 members as of Friday.

That's where painting conservator Lauren Lewis saw photos of the piece for the first time, along with the poster's caption "Is this real?"

At first, Lewis thought, "Nobody's going to find an original painting and not know what they have," Lewis told Insider.

But after inspecting the photos more closely, Lewis realized it actually could be a genuine Wyeth work, so she reached out to the poster.

"We had a long phone conversation," Lewis told Insider. "And it was clear to me that she really didn't know what she had. She just kept saying, 'I don't know anything about art. I don't know anything about this artist.'"

Lewis drove three hours to see the painting in person, and when she first laid eyes on it, she said she got a little choked up. She realized she was one of the first art experts to see the rediscovered painting — a genuine N. C. Wyeth painting that had been lost for 80 years.

Wyeth created the painting as one of four illustrations for a 1939 edition of a novel called "Ramona" by Helen Hunt Jackson, originally written in 1884. And even the painting's frame, Lewis said, appeared to be one that Wyeth chose for the work himself.

Lewis said experts knew that the painting existed because it was printed in the book, but had no information about it.

"We didn't know the size, we didn't know the location, we didn't know anything else about it except just the image," Lewis said.

"It was not uncommon for publishers to just give away the original paintings that were done as illustrations," Lewis explained. "They weren't considered valuable either to the artist or to the publisher after they were done ... being published."

Previous attempts to track down the original work had only hit dead ends, Lewis said.

"The fascination of the art world is that anything can turn up anywhere," Henry Adams, an art history professor and Wyeth expert, told Insider. "This kind of thing does happen, but this would be a dramatic example of that."

What makes the painting itself so unique, Adams said, is its subject matter. It depicts a scene from the book in which Ramona, who is Hispanic and white, tells her Spanish grandmother that she wants to marry a Native American man, Adams said.

And the way Ramona appears in the image versus the grandmother, Adams said, indicates that Wyeth sympathized with the young biracial protagonist.

"It's a subject that's very relevant today and unusual for that period when interracial marriage was often viewed with antipathy," Adams said. "This is a book and an illustration that are celebrating it."

The painting is set to be auctioned off on September 19 by Bonhams Skinner, with a listing price of $150,000 to $250,000.

Have you thrifted any rare items? Insider would like to hear from you. Email akrause@insider.com.