Most likely being exposed to the elements for decades before @paddyman98 had a chance to find it. Only other suggestion would be allowing a cent to sit in a drink holder covered in soda for a period of time. That stuff is like battery acid to a coin.
Erosion Most of the damaged Cents that I find that look like yours were found in rocks near water.. Freshwater and Saltwater have the same affect after many years submerged in wet sand.
i found it in my great grandfathers collection his coins were stored individually in little cardboard slips...my dad said he remembers this specific coin from when he was a child so...that would cancle out soda option...so i guess maybe he found it buried somewhere however...couldn't have been buried for decades...hmm anyway thanx for responding its a penny he kept forever and so will I.
