Colored sulfuric anodizing on aluminum is a surface treatment process that creates a protective oxide layer on aluminum by electrolysis. During the process, aluminum is immersed in a bath of sulfuric acid and an electric current is applied to produce a layer of aluminum oxide on the surface of the object.

The color of sulfuric anodizing depends on the selection of pigments that are deposited inside the pores created during the anodizing process. This allows for a variety of colors, including black, blue, green, red, orange, and pink.

This technique is often used to produce decorative and wear-resistant finishes on aluminum parts, such as for bicycle parts, automobile parts, aircraft parts and electronic components.