I'm not sure if its considered Powder River Basin coal or not. I'm pretty sure the coal that comes from the Gillette, WY area is considered Powder River Basin Coal. I know for a fact that it will crumble pretty easily. The coal I've been getting from Decker seems to be much better coal than the coal from Gillette. It seems to be much harder and burns hotter with less ash and clinkers. In fact, I've only had a few clinkers in the two years I've been burning it. It burns to a fine powder ash. If I burn the stove pretty hot during really cold weather, the ash will clinker a little, but not much. The so called "clinkers" are maybe 1/4" in diameter. The Gillette coal I've had experience with seemed to have lots of clay or dirt in it and seemed to make lots of clinker like stuff. It also seemed like from a 5 gallon pail of coal, yod would get 7 gallons of ash. lol Well maybe not quite that bad, but it did produce alot of ash. I'm much happier with the Decker coal. One thing I do notice about the decker coal is that it has a lot of violatles. I've had some pretty good puff backs if I get lazy and shut the air down too early after reloading. If I take the time and give it plenty of air after loading and "bank" the coal I don't have any troubles however. Since the puffbacks, I have names my stove "puff the dragon." lol If you have any more questions about coal from Decker, let me know. I'll try to answer your questions to the best that I can.