Digging whisper tones in a junk field

I was at an old park where there is an old ball field, plus back in the forties and fifties they used to hold kite flying competitions. A big open meadow and field. Well needless to say there is a ton of junk, pull tabs etc, I've been digging the faint tones that sound good and so far I have found 6 Wheaties ranging from 1940 to 1956. Waiting to find some silver, I know its there, I just have to be patient.