A reel-to-reel tape containing what’s thought to be the first demo of David Bowie track “Starman” will be auctioned after its current owner rediscovered the treasure in his attic.

Kevin Hutchinson was 16 when he was given the tape soon after it was recorded in 1971 by his friend Mick Ronson. Conversation during the session appears to suggest that it was the first time Bowie’s guitarist had heard the song. The tape also contains demos of “Moonage Daydream” and “Hang On to Yourself,” both of which appeared alongside “Starman” on Bowie’s 1972 album The Rise and Fall of Ziggy Stardust and the Spiders from Mars.

Hutchinson only listened once before writing “David Bowie rehearsal tape” on the cover, and eventually putting the box in storage. The tape remained there until he found it two years ago. “I remember listening to it and thinking, ‘This is OK,’” he told the BBC. “I didn’t think, ‘This is fantastic.' At 16, you’re not totally impressed. Nothing impresses you.”

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Auction manager Dan Hampson said: “There's a lot of Bowie mythology around the writing of this timeless classic, and the raw and truly beautiful version heard here helps to provide a fascinating insight into the creative process of a bona fide genius.”

Hutchinson added: “You can tell that Mick has never heard the song before, because at the end he is just about to turn the tape recorder off and Bowie says, ‘Hang on. There’s a little bit more.'"

The auction closes on Tuesday (March 12). Bids had already gone as high as £8000 ($10,470), with an expected sale price of at least £10,000 ($13,080).

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