Hair appears brassy when there are orange, orange-yellow and yellow pigments in the hair. In the salon, stylists tone down brassy locks by coloring the hair with pigments found opposite on the color wheel, namely blue-green, blue and blue-violet. This same color theory can be applied at home to counteract brassiness.
According to Beauty Editor, colored hair often fades and becomes brassy because blue color molecules leave the hair shaft first due to their small size. Since a balance of all pigments is needed for natural color, this loss makes hair appear brassy or unusually orange and red. To place more blue pigment into the hair shaft, use a purple color-correcting shampoo at least once per week. For extreme cases of brassiness, use the product every time you shampoo until the desired color balance is achieved.
Hair can also turn brassy due to chlorine and mineral deposits found in the water in your home. Porous hair can absorb these deposits, resulting in a reddish hue. Beauty Editor recommends purchasing a filtering shower head and using a clarifying shampoo weekly to remove mineral deposits from your hair. Once brassiness is removed, keep it at bay by maintaining the overall health of your hair.