Maybe you are thinking it's a die adjustment strike, an early strike trying to determine the die pressure needed......possibly.....heavily grease filled die seems plausible but as mentioned, it should have the upset rim still......my initial thought too was a grinding wheel but I can't understand how Jefferson's nose was not affected......so I am going to go with PMD although I am not at all familiar with the many implements of destruction that are out there so I just can't say how it might have been done.
HH all!
Greg