Alice Cooper discovered a forgotten Andy Warhol print "rolled up in a tube" after it spent 40 years in a storage locker.

The 'School's Out' singer had kept the red Little Electric Chair silkscreen - a gift from his former girlfriend Cindy Lang - with a number of his old stage artefacts but was urged to dig it out four years ago when art dealer Ruth Bloom told the rocker's manager Shep Gordon how much one of the artist's pieces had recently sold for at auction, and he urged his client to find the print.

Shep said: "Alice's mother remembered it going into storage. So we went and found it rolled up in a tube."

It was then suggested Alice hang the print at home but, as another piece from the collection previously sold for $11.6 million, the 69-year-old singer wasn't keen to have something with such a high value in his house and returned it to storage.

The picture cannot be verified because it is unsigned, but Warhol expert Richard Polsky has seen the print and is "100%" certain it is genuine.

And Alice is now considering hanging it in his home when he comes off tour at the end of the year.

Shep told The Guardian newspaper: "Truthfully, at the time no one thought it had any real value.

"Andy Warhol was not 'Andy Warhol' back then. And it was all a swirl of drugs and drinking. But you should have seen Alice's face when Richard Polsky's estimate came in. His jaw dropped and he looked at me. 'Are you serious? I own that!'"

While Alice thinks he had a conversation with the late artist, who he befriended in the early 1970s, about the piece, he was drinking so heavily at the time, he can't be certain his memory is reliable.

Shep said: "It was back in 72 and Alice had moved to New York with his girlfriend Cindy Lang.

"Andy was kind of a groupie, and so was Alice. They loved famous people. So they started a relationship, and they loved to hang out...

"As I recall, Cindy came to me for $2,500 for the painting. At the time Alice is making two albums a year and touring the rest of the time. It was a rock'n'roll time, none of us thought about anything. He ends up going into an insane asylum for his drinking and then leaves New York for LA.

"Alice says he remembers having a conversation with Warhol about the picture. He thinks the conversation was real, but he couldn't put his hand on a Bible and say that it was."