Would love your thoughts on this one. It is raised to the same height pretty much as the lettering, almost if a drip fell there during the minting process. I am still new at this, so would love some insight into this mark. Thank you. Mark is right above the M in America
Cents Minted after mid 1982 are Copper Plated Zinc. They have issues with the plating. As mentioned, it's a plating blister/bubble.