Consider that salt based minerals will be activated by water which are difficult for single freq detectors to eliminate (falsing and senstivity loss). Iron filaments in the soil can when moistened become more reactive and create stronger eddies - which in-turn increases falsing and depth of detection for unwanted iron (to include so-called halos around deteriorated iron). This can cause iron and salts to be more problematic, assuming the soil has these minerals, with resultant depth/sensitivity loss and increased falsing.
On the flip side, digging in moist soil is easier. Yet again, if soil is abundantly wet (porus soils especially) it is possilbe for coins to slip deeper, making them harder to find next time out. If it is winter, damp soil when frozen overnight may push taragets upward toward the surface making them easier to find. Still, damped soil can settle the individual grains and result in denser (more compact) soil, which brings the surface soil down through compactation and thereby decreases the depth of the buried target, making it easier to find. But if you have a cheaply made coil, wet grass on the coil without proper shielding can cause falsing as the coil moves about due to capacitance changes, which is unwanted.
Johnnyanglo
