I have a 2007 penny with a small raised bump right next to the 7... Can anybody tell me what kind of die error this is called?
Since your Cent is Copper Plated Zinc it could be just a case of Zinc Deterioration In other words a plating issue. Zinc Bubble. I want to share this webpage with you - http://www.error-ref.com/zinc-deterioration-on-lincoln-cents/