You probably don't want to know what happened to that Lincoln cent. That coin might as well be an open-air petri dish at this point.
Harsh Chemical exposure damage. The copper plating was compromised and the inner zinc started to rot. Zincolns suck. Not a Mint Error of any kind.
Hey Mountain Man, we can call it Zincvid-20, what do yo think? By the way, it is just PMD, very common with zincolns sorry. Thanks for the post.
could id be that someone tried cleaning the coin, put some kind of cleaner on the coin and the person got distracted and just forgot about the coin and when he did remember about it but it was to late. having been forgotten the cleaner became rock hard and at that time it was just to late