Mica

Mica is a series of silicate minerals (CAS #12001-26-2) with varying chemical composition but similar physical properties, including well-defined cleavage that allows splitting into very thin sheets. It comes in different particle sizes and is widely used in cosmetics as a multi-tasker. It can improve skin feel, increase product slip, give light-reflecting properties, enhance skin adhesion, and serve as an anti-caking agent. It is also the most commonly used base material for layered composite pigments such as pearl-effect pigments, where it is coated with metal oxides like titanium dioxide to achieve a pearl effect via optical interference.