Rob Henke — A field guide to metal detecting: coil | robhenke.com
The 0-95 scale is a shortlist of suspects, not a verdict — here is what each band usually holds.
On most machines the target ID runs from 0 to 95. The number estimates how the target conducts, so it groups metals by behaviour rather than by name — which is why a pull-tab can impersonate a gold ring.
Iron reads about 10-25. That band holds nails, wire and rusted junk, but it is not safe to ignore entirely: once a coin sits much past 15 cm down, its signal can start reading as low iron, so a deep coin can land in the same numbers as a nail.
Pull-tabs and ring-pulls read about 20-35, overlapping the top of iron. No notch removes them without also removing small gold, which is why experienced detectorists dig them on clean sites and curse them anyway.
On narrow screens, swipe or scroll the plate sideways.
British hammered copper coins read about 45-55, and US coins about 55-70. These are the bands most coin shooters memorise first, and the bands where a stable, repeating number most often means something worth a careful hole.
Confidence comes from repetition, not from the number itself. A target that returns the same ID across 3-4 sweeps from different directions is telling you something; a number that wanders between passes is junk, ground noise or a target at the edge of the coil's reach.
The usable discrimination spacing is 8-12 inches of coil-to-target separation. Sweep slowly, overlap passes, and let the machine see the target from two angles before deciding — the coil page shows why depth and spacing are the same problem.
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