Hello, I am buying coal from a coal yard in Escanaba Michigan and it is used by a paper mill and a power plant. It is in various sizes mostly nut and fine rice size. This is my first time burning bituminous coal and it does seems to be awful sooty and I will be cleaning my flue once a month cause I need to. The coal burns well, no complaints there but I guess I am wondering if buying large sized coal would be better for me, I have an Esse Vista stove and have burnt anthracite before but got tired of the high price of bagged coal, it might be worth it though. any advice appreciated.