This subject comes up so often it is time to get it into its own thread so I can just link to it in the future. It is best to think of metal detectors made for prospecting as "nugget detectors" as that is the truth of the matter. Nuggets have some size to them. Metal detectors are electromagnetic devices, and as such can detect items that are conductive and non-magnetic, like gold, or non-conductive but magnetic, like magnetite. Or both, like metallic iron. When dealing with gold