Electroplating:

Electroplating is to make usage of electrolytic principle to plate a thin layer of metal or alloy on some kinds of metals’ surface, which is a technology by means of electrolytic action to adhese metal file on metals or other material surface, in order to prevent metal oxides (eg rust), improve abrasion resistance, electrical conductivity, reflectivity and enhance aesthetic effects. Many coin outer layer are plated.

electroplating