Abstract: A cathode for the electrolytic deposition of non-ferrous metals has a plate (1) which, starting from at least one of its vertical edges, is provided on both sides with coinciding zones (5) of dielectric material. The dielectric material is located where a number of penetrators that cause the upper edges of the deposited layers of zinc to detach contact the plate. The plate (1) is provided with a slot (7) that coincides with upper regions of the dielectric material. The slot has a flat piece (5) of dielectric material in it, equal in thickness to the plate (1) and with surfaces which are flat and coplanar with those of the plate (1). The piece (5) and the slot (7) are provided with mutually cooperating portions that prevent the movement of the piece in any direction.