The various specifications used in the anodising process, three of which are types of aluminium anodisation (chromic acid anodising, sulfric acid anodising and sulfric acid hardcoat anodising), but also non-aluminium based types such as phosphoric acid anodising, organic acid anodising, plasma electrolytic oxidation, and borate and tartrate baths.
DATA SOURCED FROM ESCO (EUROPEAN COMMISSION) & O*NET (U.S. DEPARTMENT OF LABOR)