Chemical Conversion coatings, also known as Chem Film, Iridite, Alodine…etc, are Conversion coatings, typically produced by Chromates and are thin protective coatings or layers of chromium oxide and other chemical compounds. They can be used to treat aluminum, zinc, cadmium, copper, silver, magnesium and their alloys. These coatings are used to provide a surface suitable to be painted and to enhance corrosion resistance where low electrical resistance is desired. The natural coloration of this coating can range from a translucent clear to a golden yellow and up to t brown color and are acknowledged as Type I. RoHs complaint conversion coatings are produced using trivalent chromates which are environmental friendly and are now available. These coatings are clear to a lightly bluish translucent colored and are now acknowledged by the MIL-DTL-5541 specification as Type II coatings.