Went back to a field that has given up several CW treasures including a US belt plate. Had a weak one way signal but saw the VDI shoot sky high on one pass. Dug a six inch plug and started breaking it up and running it over the cool. When it was so small that I knew nothing could be in it the detector still screamed. Broke the dirt clod up and saw this tiny silver disc fall to the ground. I'm pretty sure I let out a big whoop when I realized what it was. Turned out to be an 1851. I also found an 1868 shield nickel as well.