High Quality Content by WIKIPEDIA articles! Chromate conversion coating is a type of conversion coating used to passivate aluminum, zinc, cadmium, copper, silver, magnesium, and tin alloys. It is primarily used as a corrosion inhibitor, primer, decorative finish, or to retain electrical conductivity. The process is named after the chromate found in the chromic acid used in the bath, more commonly known as hexavalent chromium. This type of bath is still the most widely used, however hexavalent chromium is toxic and, thus, highly regulated, so new non-hexavalent chromium based processes are becoming commercially available.