Leslie, the drawing to which I referred you was done on plain white Canson Mi-tientes paper, on the smooth side. I used three hardnesses of charcoal to help -- the lighter the value, the harder the charcoal used, and then the darker, the softer. This prevents your having to grind charcoal into the paper to get a dark value. I sandpapered the charcoal sticks to a sharp point, and used them in conjunction with a kneaded eraser, also shaped to have a sharp point. It's a slow drawing method but works well to get a certain result.
I haven't seen the drawing for some years now (it's in storage in the U.S.) but it was done sight-size, with the easel next to the cast, so I guess the dimensions of the cast must have been roughly 18 x 12 inches, since as I recall, the Canson paper runs about 25 x 19 inches. (I could go check, but that's close enough for our purposes.)