An electrical lead assembly for devices such as electrical lamps having a metallic foil for providing an electrically conducting path through a hermetic seal formed by pinch sealing a vitreous material. The metallic foil includes an oxidation-inhibiting coating of silica. In another aspect of the invention, methods of coating metallic foils with silica are disclosed. In yet another aspect of the present invention, an electrical lead assembly for lamps is provided wherein the metallic foil is extended to form an outer electrical lead for the lamp.