The hard material coatings chromium (Cr) and chromium nitride (CrN) optimally protect engine components such as piston rings against premature wear and consequently extend the useful life of important engine parts. Chromium is used as a bonding layer for DLC coatings (Diamond Like Carbon), for example on bucket tappets. Furthermore, when used as a decorative coating, our chromium gives watches, electronic goods, operating elements on appliances and a range of other products an attractive sheen.