Thank you! So, I guess I'll have to get out the hammer.
I found a pile of "West Virginia's Finest" along US 52 back in 2012, and collected a gallon. This was modern, machine-dug, coal, the biggest pieces about the size of an egg, down to dust. The first screen I used was 1/8 inch hardware cloth, assuming that nobody would want a chunk bigger than 20 inches (N scale). No, it isn't the highest quality coal - much of what's dug today, even in "Coal County", isn't. It's just generic power plant coal, but that's fine for hopper loads. And there's a lot in a gallon,
