I have seen vidioes getting a slugg on top of a stone but not under a stone and in my finding if your disq is set to knock out a nail you will loose the slugg like any other detector I had to basically put it into all metal to get the slugg under the stone and slow the sweep this is the truth of the blisstool ask me if i like the detector yes its great i would highly recomend it it easaly getts dimes at 10" thru my badd ground but it does have its draw backs in certian eareas nails pointing up will sound like a good target bottle caps sound good and it gets fussy in around Emi[video]http://www.youtube.com/watch?v=DQo8bVLSzqg&feature=relmfu[/video]