Update: I posted this to another forum where Mike Diamond remarked:
Quote:
It looks a little too well-defined to be a gas bubble. But you should gently press on it with the tip of a toothpick to see if it flexes. My hunch is that it's a die dent.
It looks a little too well-defined to be a gas bubble. But you should gently press on it with the tip of a toothpick to see if it flexes. My hunch is that it's a die dent.





















