My ACE loves dimes and will ring one up like it is going to a fire! I only use it for coin shooting and I discriminate out foil. Even without discriminating out foil it sounds different on my ACE, usually ringing up as a penny rather than a dime on my machine. Using a burried dime and a similar piece of foil, try backing off your sensitivity a notch at a time until you can hear the difference. Another thing I noticed just recently is that if you are detecting in grass with a heavy dew you may have to back your sensitivity way down to about two notches. The wet grass acts almost like water sometime...sometimes it don't . You just have to expriment at the time and it only takes a few minutes to figure it out. I read in one book on detecting to think of sensitivity as depth, but with it turned way down I am still getting targets at 6". Of course I have no way of knowing if I am missing some unless I turn the sensitivity up and go back over the same area. In my experimenting, most of what I am missing is trash. JIM