Silver #19 and it is a first!

[WildDigger]

Went on a short hunt and hit the old court house. They use is for storage now. Only found 1 good find and it was a 1936 Six Pence. Silver and sweet!!!! Don't know how it got to Winder Ga but I like it. It was in a hole with some iron and !!!!. It was about 6 to 7 in down. also found a 1919 wheat and a little gun.

How can I clean this off?