I dont see how this could have happened at the mint. Looks like the copper was very neatly taken off exposing the zinc underneath. A nice hexigon too. Looks like a bullet hole to the head. Its so tiny ! Usually it shows alot of surrounding damage.
Plating bubble most likely. Very common in post 82 cents. Have something like this on the coin, it gets buried in the ground, and a few years later the coin is simply gone.
I tossed it back in the coinstar pile. I think it was a mid 90s because I had it in a stack to check for WAMs.