(click to enlarge)
I acquired a bunch of camping gear from a friend who moved out of the country. There was one of these hockey puck shaped disks, half grey half black, remaining in the cooking gear, but I have not a clue how to use it, and the friend is out of contact for a few months. I tried holding a lighter to it, expecting it to be some kind of cooking charcoal pellet, but it didn’t catch on fire. How do I use it? Or is it for something else entirely? I googled and googled and can’t figure out what it is used for.