So I was in a public park where the property dates back to the 1790s as farm land. I was going through the woods and found a few items which I am not sure of including a coin. Any help would be appreciated. They coin is slightly larger than a quarter but seems thin. I know the one part is a clock circle (sprocket). I know the one piece is a makeup compact. The jar is a Maryland Nox jar. It is the oval silver colored thing and coin (if a coin) I am at a loss for. The coin also has a jagged tooth or so on the edge. I wasn't sure if that was from corrosion or what.