A record collector has found 149 unknown Bob Dylan acetate discs which the musician used during the making of the Nashville Skyline, Self Portrait and New Morning albums.

Some of the acetates are already up for sale, the most expensive item currently being two one-sided discs that comprise an alternate sequence for Nashville Skyline. The two discs are listed at $7,000 (over 5,000 Euros).

The acetates were discovered during the sale of the estate of a woman who had lived at West Houston Street in Greenwich Village in New York.

Bob Dylan had rented rooms there in the late 1960s and early 70s. The woman’s brother found two boxes labelled "Old Records", with labels bearing Dylan's name.

He then contacted record collector Jeff Gold, who was "blown away" by the rare find. Outtakes include full-band covers of Johnny Cash's Ring of Fire and Folsom Prison Blues.

Dylan's Like a Rolling Stone lyric manuscript recently fetched $2.045m at auction.