Yes it is. IF it is good coal. All coal is not the same. For forging you need a low sulpher, low volatile, high BTU coal that cokes well. Most coal sold for home heating, used for coal burning electrical power generating plants, etc will not work well. If you have access to a local source of good blacksmithing coal, then you are fortunate. It is getting harder to find good blacksmithing coal, and many people have gone to propane forges because of this.