I'm looking for help in identifying this non magnetic item I found this past weekend in the Brandywine Creek just south of Smithbridge Road in Beaver Valley,DE. A few miles upstream the Battle of Brandywine was fought on Sept. 11, 1777 It weighs .64 oz. I wirebrushed the rear of it and it looks like Silver. It showed 81 on the VDI on my ATPRO.