NEW YORK, NY.- Paul Brown, an antiques collector from Lancaster, Pennsylvania, said that he typically collects 19th-century grocery store products, old gas station signs and advertising — pieces of Americana that he can haul away in the back of his Chevy pickup truck.

But last fall, he decided to buy two large round windows that were covered in grime and encased high in the stone walls of a dilapidated Gothic Revival church in West Philadelphia, which was built in 1901 and had originally been named St. Paul’s Presbyterian Church.

The church’s new owner, the Emmanuel Christian Center, planned to get rid of the windows to convert the building into a worship space and youth center for its 400 members.

Brown, 56, said he had heard about the windows on Facebook Marketplace and ran into a salvager he knew at the church, who told him, “Do you want to get these windows out before we sledgehammer them out?”

Brown said he paid $6,000 for the windows, as well as some wooden pews and doors, and hired workers who spent weeks on scaffolds, grinding and cutting the glass out of the wall.

He packed the pieces in moving blankets, put them in the back of his truck and took them to Freeman’s, a Philadelphia auction house, to have them appraised, he said.

What the auction house told him days later was a shock, he said.

According to Freeman’s, the rose windows, roughly 8 feet in diameter, had been crafted in about 1904 by Tiffany Studios, the renowned New York firm founded by Louis Comfort Tiffany, the Gilded Age designer known for his ornate leaded-glass lamps.

Both windows are slated for auction May 18 and have an estimated value of $150,000 to $250,000 each, Freeman’s said.

Brown said that he had no idea that the windows were made of Tiffany glass when he bought them in a deal previously reported by The Philadelphia Inquirer.

“To be honest, Tiffany, in my world, has always been lamps, not windows,” he said.

He said he had paid $15,000 to have the windows removed because they were “round and big and they had purple in them.”

“From what I gathered, round windows were not common,” he said. “I thought, for the unique size and colors, someone’s got to want them.”

After learning that they had been made by Tiffany Studios, he paid an additional $50,000 to have the windows restored, he said.

William A. Brownlee Sr., the senior pastor of Emmanuel Christian Center, said he had no idea that the windows were valuable when he sold them to Brown. Brownlee said that he had asked his contractor to get rid of them because, to his eyes, they were not salvageable. The windows, he said, appeared to be cracked and coated in mold and grime.

“I feel embarrassed that I didn’t know,” Brownlee said. “I feel like, because I didn’t have a knowledgeable team, my ignorance was taken advantage of.”

But it may be that nobody knew that the church had Tiffany windows.

In 2021, when a local historical society submitted a nomination to have the church listed on the Philadelphia Register of Historic Places, its report on the building’s historical significance did not mention Tiffany glass. And the group dropped its nomination last year amid opposition by the Hickman Temple African Methodist Episcopal Church, which had owned the church since 1972 and sold it to the Emmanuel Christian Center last year for about $1.7 million, according to records. Hickman’s leaders had expressed concern that the designation would hurt the value of the property, Axios reported.

Identifying Tiffany windows is difficult, especially if they are caked in dirt, said Carl Heck, a collector from Aspen, Colorado, who has been collecting the windows since the 1970s. Some Tiffany windows are signed, but most are not, he said.

“How do you tell if a painting was Rembrandt or Picasso?” he said. “You could look at the style or brushwork or things like that. But it takes an expert — somebody who has done it a long time.”

Tim Andreadis, the director of decorative arts and design at Freeman’s, said the auction house was able to authenticate the windows by consulting with experts. St. Paul’s Presbyterian Church was also referenced in a list of window patrons published by Tiffany Studios in 1910, he said.

The windows, he said, were originally commissioned for an auxiliary chapel to accommodate St. Paul’s affluent and growing congregation and Sunday school.

One of the windows depicts a crown, representing Christ, at its center. The other features a dove, representing the Holy Spirit, with a cross at its center that is revealed only when light passes through its layered glass.

Although Tiffany may be best known for his lamps, his studio made dozens of rose windows for churches across the country, and even more vertically oriented lancet windows, which were often dedicated in memory of the family members of wealthy church members, Andreadis said.

“Tiffany was the gold standard that wealthy donors turned to support their churches,” Andreadis said.

Brownlee said he was looking for his own donors to help him renovate the future home of the Emmanuel Christian Center. The church has a brace holding up a wall, mold and asbestos, a bell tower that is falling down and major damage to the roof, he said.

“These windows are $250,000, and we need that much to get the work done,” Brownlee said. “I would have kept them if I had known that.”

This article originally appeared in The New York Times.