Kesselstone was a mineral that was mined in the spice mines of Kessel to retrieve Kessel spice. Chunks of kesselstone could be ground into powder, which was then used by criminals to create a powerful narcotic. While mining for it, Kessoline, a toxic fossil fuel, was released into Kessel's atmosphere.
- Solo: A Star Wars Story (First appearance)
- Solo: A Star Wars Story The Official Guide (First identified as Kesselstone)
- Solo: A Star Wars Story: Tales from Vandor