These are the last pictures that I'll post of this coin as it is going in the safe. There were a couple of places on the coin that were cankered a little. These were the green looking spots in the original pictures. All the black gunk was removed with acetone. There was or is no corrosion on any of the nickel surfaces only had a couple on the copper and they were quite small. They show up in the pictures as a dark spot. The copper area has what appears to be and is commonly called woodgrain on a coin where the alloy wasn't mixed thoroughly.
I have to ask all you chemistry experts how or what chemical reaction you are basing your answers on? It would have to be one that will remove the nickel from a copper nickel alloy and leave only the copper. Also can you post any pictures of a coin that closely or remotely resembles the ones posted here? I'm done with this.