The state of iron deposited at constant potential, on HMDE, was studied by means of the influence of stripping rate on the dissolution peak obtained by anodic stripping polarography, and also by means of radioactive tracers.

If reduction potential is not too negative (>−1.55 V vs. Ag/AgCl, in KSCN 2M), iron stays on the electrode surface. In the opposite case, iron penetrates into the electrode, but it can no more be reoxidized by anodic stripping.

The great sharpness of dissolution peak of iron is attributed to the physical state of the deposit. This metal is perhaps deposited like microcrystals.