As part of the celebration of Workingman’s Dead‘s 50th anniversary, the Grateful Dead have released ‘The Angel’s Share,’ which features “more than two-and-a-half hours of unreleased studio outtakes from the album’s recording sessions.”

According to a press release: “Compiled from dozens of 16-track reels that were recently discovered in unlabeled boxes, the collection includes outtakes for every song on the album, which have been unheard since they left the studio over 50 years ago. Under the supervision of Grateful Dead legacy manager David Lemieux, engineer Brian Kehew and archivist Mike Johnson spent countless hours compiling and piecing these reels together to create the final opus.”

The release continues: “The collection takes its name from a term used by whiskey distillers. The ‘angel’s share’ is the percentage of whiskey that’s lost to evaporation each year as the liquid is aged in oak barrels. Much like the whiskey distillation process, there were also ingredients that were vital to the creation of Workingman’s Dead that were lost and did not end up on the final album, the band’s own version of the ‘angel’s share’.”

The new compilation is available to stream now; to listen to it, click here. The collection comes ahead of Workingman’s Dead 50th Anniversary box set, which will drop on July 10.