J Rocc was doing a set of new tracks on Benji B's BBC Radio 1 show to promote his upcoming solo album Some Cold Rock Stuf (Stones Throw) when he dropped a bomb: a new Black Star track produced by Madlib. It’s an untitled two-minute non-stop burst of Mos Def's skills that cuts off before (presumably) Kweli’s verse. No one seems to know what the deal is, but whether it’s a tease at a real sequel to Black Star’s classic thirteen-year-old debut, the follow-up to Mos’ The Ecstatic, or just a one-off that we’ll never hear about again, it’s always great to hear two of the best MCs out there at work. Stream the cut over at Culture King, or download a rip of it here.

If that clip leaves you wanting more Kweli – which no one could blame you for – you’re in luck: on January 25, he’s dropping a new album called Gutter Rainbows on his own Talibra imprint. You can stream the whole album now on his Myspace, and watch the video for “I’m On One” right here.