Large copper disk with a few letters and numbers and a bust ?

[Deepdiger60]

I went back to the old field today not much but a copper disk much larger then a dollar piece i can see a bust just to the left of a dent in the middle facing left and there is a few numbers on it 8 and 7 and some letters on the top i used the LC as a size reference plus i dug 3 clad quarters in 1 hole all 1970,s strange seeing new with the old . Good hunting Dd60