Nordic RoyalTM is an alloy of copper with aluminium and zinc, giving it a rich golden though-colour and making it very stable. It has a thin protective oxide layer containing all three alloy elements when produced. As a result, the surface retains its golden colour and simply loses some of its sheen as the oxide layer thickens with exposure to the atmosphere to give a matt finish. It behaves differently to other Aurubis copper products over time and does not develop a blue or green patina.
Facades clad with Nordic RoyalTM convey a distinctive, pleasing and unique quality. In order to maintain this lasting impression, the surfaces changes little over time. Further colour changes due to oxidation processes are much less dramatic compared with mill-finished copper.