We’ll never know what the final fruits of Joni Mitchell’s collaboration with jazz legend Charles Mingus might’ve sounded like. Mingus died before the project was completed, and not surprisingly, the album ultimately released has the feel of a rough draft rather than a polished work. Still, Mingus (1979) holds considerable interest for Mitchell fans, both in terms of its historical value and for the haunting, risk-taking nature of the music itself. There’s both an air of intoxication and a pervasive note of sadness to these tracks, as if Joni is serenading Charles’ ghost in some otherworldly nightclub. “A Chair in the Sky” and “Sweet Sucker Dance” combine swooning melodies with urbane, slightly woozy lyrics, underscored by Jaco Pastorius’ burbling bass and Herbie Hancock’s cascading piano. Mitchell conducts a bopping visit to Vegas in “The Dry Cleaner From Des Moines” and reworks Mingus’ standard “Goodbye Pork Pie Hat” into a bittersweet elegy for its composer. You can’t help wondering how these sessions would’ve turned out with Mingus’ participation. As it is, Mingus occupies a unique place in Mitchell’s catalog, sketchy in spots but touched by fitful brilliance.