<p>A base for a decorative layer is provided comprising a first material capable of forming an anodic oxide and a second capable of forming an interference metal oxide formed on the first material. The material capable of forming an anodic oxide layer may comprise a barrier layer formed on a substrate. A decorative layer is formed by anodic oxidation of the layer comprising a material capable of forming an interference metal oxide to form an oxide layer formed on the material capable of forming an interference metal oxide, wherein the oxide layer is configured to have a thickness suitable to cause interference of incident light.</p>
