An illuminator serum is a cosmetic product that is intended to give the skin a luminous and radiant appearance. It is usually made up of light-reflecting particles or components that serve to generate a slight glow or highlight on the face. Illuminator serums are frequently used to give the skin a natural, dewy, or radiant appearance. They can be applied to particular parts of the skin or blended with foundation or moisturiser for an all-over glow.