The winged D. Yes there is a RPM. But the majority that you see on that MM is a die chip. They call these Winged D's, after the Winged Liberty or Mercury dime. Let me see if I can find mine.
I believe there are 4 or more different stages to this Winged D, I believe mine is the 3rd or 4th stage. I can't remember. Yes, there is a chip on the 9 and a very light die crack.