Question: What Is the Difference Between Chrome and Chromium?
Have you ever wondered what the difference is between chrome and chromium? Chromium
is an element. It is a hard, corrosion-resistant transition metal. Chrome, which you may see as decorative trim on cars and motorcycles or to harden tools used for industrial processes, is an electroplated layer of chromium over another metal. Either hexavalent chromium or trivalent chromium may be used to produce chrome. The electroplating chemicals for both processes are toxic and regulated in many countries. Hexavalent chromium is extremely toxic, so trivalent chrome or tri-chrome tends to be more popular for modern applications. In 2007 hexa-chrome was banned for use on automobiles in Europe. Some chrome for industrial uses remains hexa-chrome because the corrosion resistance of hexa-chrome plating tends to exceed that of tri-chrome plating.
It's interesting to note that prior to the 1920's the decorating plating on automobiles was nickel and not chrome.