One of the most disappointing moments in Hip-Hop relates not to something that happened, but rather something that didn’t. After releasing the nearly universally acclaimed album Mos Def & Talib Kweli Are Black Star, Yasiin Bey (pka Mos Def) and Talib never united again for a follow up. At the time, for many, that album was the first exposure of the two masterful MCs and it seemed they were a group destined for a catalog of classics. In reality, the two had been hard at work for years, both as solo artists and as part of other collectives, and the Black Star project was simply another gem in the expanding repertoire of Rawkus Records.

Over the years, Black Star have released a song here and there to whet fans’ appetites for more, but another full collaboration has yet to surface. There are still some jewels though, that while they’ve been around the Web for a while, may not have been heard by all.

One such recording is this freestyle between Mos and Talib on a Baltimore radio Reflection Eternal/Black Star takeover. The two MCs trade off the top verses for nearly 6 minutes, building momentum as they go. As with all true freestyles, the rhymes are not perfect, but showcase the talents and fearlessness of both artists. Check it out.

Related: Black Star perform at the Lyricist Lounge 20th Anniversary Celebration (Video)