About ten years ago I was given what I think maybe an 8" solid shot. It weights about 63.5lbs and is alittle less than 8" in diameter which is what I would expect if that indeed is what it is. It has a dark patina overall and is not pitted. However, evenly spaced around the circumference of the ball are 4 small circular endentions or holes, which look either to be lathe marks or where the tips of lifting hooks could be inserted. Anybody ever seen anything like this? Do I have a cannonball or a mill ball?