Anodizing is an electrochemical conversion process that forms an oxide film, usually on aluminium, in an electrolyte (chemical solution). The aluminium parts are the anode (thus the term “anodizing”) and current is passed between them and a cathode, usually flat aluminium bars, through the above mentioned electrolyte (sulphuric acid is most commonly used). There are different types of anodize, most commonly referred to as Type I-Chromic Acid Anodize, Type II-Sulphuric Acid Anodize, and Type III Hard Anodize or Hard coat from the Mil-A-8625 designation. Other less common types are phosphoric acid and titanium anodize. The anodize is a porous structure that grows out of the base aluminium and absorbs coloured dye very well. This is done through a secondary operation with either an organic or inorganic colouring. Manideep processes black, blue, red, gold, as well as small lots of green and gray using standard organic dyes. We also do electrolytic colouring which produces a gray-black colour using inorganic metallic salts. Any coloured anodize is required to be sealed following processing in order to preserve the colour.