The little bit I know about chrome is (and could be wrong) that the older and better ways used copper underneath to fill in the rougher spots. When the chrome was applied over the top of the copper and buffed out, it made better shine and smoother finish. Many rechromers use nickel instead of copper. It is cheaper and adequate in most cases. The guys who still use copper are a lot more expensive and most show cars use the copper process over the nickel.
