Grammy-winning keyboardist Dr. Fink announced the auction of an unreleased Prince album later this week and said he didn’t feel any guilt at parting with it.Matt Fink worked with Prince from the late ‘70s until the early ‘90s, mainly as a member of The Revolution, and was part of Prince’s short-lived Rebels side-project, who in 1979 recorded the unreleased album currently being auctioned by Fink. The Rebels also featured Dez Dickerson, André Cymone, Gayle Chapman and Bobby Z.The record was never released because the label didn’t want to dilute Prince’s image after he’d already put out two albums under his own name.READ MORE: Was Prince’s Famous Rock Hall Guitar Solo an ‘Act of Revenge’?“Prince did it on the sly,” Fink told the Star Tribune in a new interview, “and then came to Warners after the fact and said, ‘Look what I did. Can you do something with this?’” He added: “That Rebels cassette has been out there as bootlegs [but] I’ve never bootlegged anything.”The auction takes place on Nov. 15 via the U.K.-based Popstore. Among the lots on offer from Fink are an ‘80s Oberheim OB-8 synth used on tour with Prince, a tour-used mixing desk, 39 cassette tapes recorded during rehearsals with Prince, a draft script for Purple Rain, a number of gold and platinum discs and a range of stage costumes and tour shirts.Why Dr. Fink is Selling His Prince MemorabiliaThe 66-year-old noted that he was keeping some of his most prized items – including his Grammy for the Purple Rain album – but that his sons weren’t interested in his collection, and also that his music career had forced him to draw down on his pension scheme.“Income is very inconsistent in this industry,” he said. “Prince did take care of us. [But] there were difficult times between then and now.”He was reported to be “neither guilty about selling nor sentimental about the items,” which run to 54 lots and are expected to sell for between $150,000 and $300,000 in total.Bids are now being taken on the Popstore website. it’s unlikely that the winner of the unreleased album will have the rights necessary to legally release it.Prince Year by Year: 1977-2016 PhotographsThe prolific, genre-blending musician’s fashion sense evolved just as often as his music during his four decades in the public eye.Gallery Credit: Matthew Wilkening