Lionel Coal

Lionel and MTH both sell coal for their accessories and that is what I use.

Mikey

Use Lionel's postwar coal. The pieces are more consistent in size, and have rounded edges like they were processed through sieves and tumblers. By contrast, Lionel's modern era coal has a wide variety of sizes, and have sharp, jagged pieces. Some are so small, they jam up coaling accessories like the belt on the 397 conveyor loader. The modern era coal just looks like someone put broken plastic bodies in a blender, then dumped them in a cloth bag.

They both are "chopped up" or crushed something. The post war version was crushed/chopped Bakelite, known not to waste anything, Lionel used the remains from finished transformers, trays... or pieces broken during manufacturing. I prefer Bakelite because it's heavier and slightly larger pieces.

Mike