showing how the blisstool handles black sand and basalt rocks like the ones in cullper VA, wile still rejecting a nail, I know a test was done with the bullet on the rock but hear it is under black sand and two basalt rocks to eather side to make it fare by the way i like the gold bug its all metal zaps thru that like nothing , but its disq need better ground , but the gold bug is a good detector to work with my blisstool , cleaning up that 1st 6" then the tool goes to the depths , but i will say the 5" gold bug coil in all metal is no wimp getting a nickle easaly at 9"[video]http://www.youtube.com/watch?v=oZ1bXwffcM4&feature=channel&list=UL[/video]