This mill was build using Chooch stone retaining wall material..(not a cheap
way to do it!), kind of a foam-like material. (accumulating the material for
a structure gives you a clue why these O scale structure kits aren't cheap).
It is a free lance design I developed from photographing a number of mills,
in SW Missouri, and, stone ones are common in Eastern Pa. (but have to be
hunted down). I plan to do a barn red wooden one, and that should do it for
me for mills.