seems to me that the difference between the classic "triple chrome plating" of steel that all the Harley guys and classic car nuts swear by (and that's copper, followed by nickel, followed by chromium) and aluminum chroming is that aluminum never has the layers of copper and nickel but just the chromium directly applied. It does not seem to stick very well, but that may be due to cleanliness of the skill of the plater. I know I've paid to have plastic parts plated with something called "chrome" and it's not a process that involves heating the plastic (obvious) or passing an electric current through it (obvious, too) but is done with "evaporation" in a chamber or cabinet, and it puts an extremely thin layer of metal on the plastic (also prone to peeling off, as we know from auto trim and model kits).