A process is disclosed for stabilizing certain colored anodized coating on aluminum articles against degradation by ultraviolet radiation. Anodized articles colored by an electrolytic or interference process can thereafter be stabilized by heat treating them at temperatures of the order of 350.degree. F. for a period of an hour or so. The process is particularly useful for use on electrolytically colored, anodized vehicular external body panels made from suitably formable sheet metal aluminum alloys.