The "never never" people will get all up in arms, but here's how the coins were restored. To dissolve the PVC contaminant, they were all soaked in lighter fluid for as long as it took to shed the stuff. Some came out of the fluid relatively quickly, while others took probably 3 hours. after that, they were rinsed with hot tap water, and then soaked in a 50% solution of ammonia and water. This left the coins basically "stripped". The final "dip" was tarnex, very quickly, into a bowl of water, and then into a bowl of water with baking soda dissolved in it to neuutralize any remaining acid. The coins were rinsed with hot water one more time, and patted dry between layers of paper towels.
There were maybe 6 coins in the entire lot that had significant etching from the PVC. None of the green contaminant was the culprit in those instances. It was the coins that had heavy "black" residue build up that were etched.
The 1904-S
Barber dime, the 1906-O
Barber dime, the Barber half ... were not even subjected to the ammonia and water. They appear much brighter than they actually are. It was a good opportunity for me to swap
Roosevelt dimes and silver
Washington quarters in my collection for some pretty nice Barbers and Morgans. The 1912-D half is a real prize in my book. I figured that with that fat, round rim that was raised so high above the field, that I was looking at a very nearly uncirculated coin. I'm actually still working on that one. There's some stubborn material on the back. It's coming off, but agonizingly slowly. The reeded edge on that coin is still sharp.
Chance
Chance