I had about 90 minutes yesterday to hit a park before dark. I decided to try a spot popular for family reunions and such. My first two hits were clad, then I pulled up a 1946 wheatie. Might be more oldies there, right? Suddenly I just hit coin after coin, none more than 1" down. I guess some parent just tossed a couple of handfuls of coins into the grass to keep the kids quiet and entertained for a few hours. Finally I quit due to darkness, but the hits were still coming. Nothing older than the 70's, but that 1946 kept me there looking.