MINNEAPOLIS — It’s considered the Holy Grail of comic books: Action Comics No. 1 from 1938, featuring the debut of Superman. And David Gonzales found one mixed in with old newspapers insulating a house he was renovating in a small town in Minnesota.

Gonzales did some research that confirmed the comic with a cover showing the Man of Steel holding a car over his head was valuable, though it’s not worth as much as it could have been.

The book sat undisturbed in the ceiling of the house in Hoffman for over 70 years. But a few days after he found it, Gonzales said, he got into a heated discussion with his wife’s aunt about its value, and she wanted a cut of the money. He said he also grew irritated because every time she would turn a page, crumbs of paper would fall out.

Finally he said, he grabbed it and tossed it aside, accidentally tearing the back cover.

“I don’t care about the money,” he recalled telling her. “I don’t care. It’s my comic book. I can burn it if I want to.”

Because of the damage, New York-based online auctioneer ComicConnect.com graded the book a 1.5 on a 10-point scale. By comparison, an Action Comics No. 1 that was graded a 9 recently fetched $2.16 million.

Bidding on Gonzales’ find was up to $127,000 as of Friday. Bidding will close June 11.