Cannon ball | The High Road
Jul 23, 2014· If I were to guess, seeing you are in MN, it is probably an iron ball for processing mining ore. These were used in "rod and ball mills" where you took your high graded iron ore, dumped it in a rotating drum with rods and balls and then rotated it so the natural weight of the ore would crush it down fine enough that the balls and rods can then finish the job up.