I have seen Burt work very similar and even dot-sizs inserts which do not
touch the edge... meaning it was a shallow indentation of composition and in several forms of running over during pressing. The biggest dot (on SmKey) was no more than 3/16-inch. They were part of the "Newhouse '94 Find" that had the $5 Harrah's Reno chips which I was accused of making in my basement since no one has ever seen those chips before I introduce them to the hobby. Problem is I don't have a basement...