Magnesium Aluminum Silicate
Magnesium Aluminum Silicate (MAS) is a clay mineral used as a helper ingredient in cosmetic formulations. Its platelets carry a negative charge on the face and a positive charge on the edge, allowing them to form a "house of cards" structure that thickens and stabilizes products. This structure also enables thixotropy — the formula is thick at rest but becomes easily spreadable upon application. It is additionally used to suspend non-soluble particles such as color pigments and inorganic sunscreens like zinc oxide and titanium dioxide.
MAS thickens and stabilizes cosmetic formulas, helps suspend insoluble particles, and provides a non-tacky, rich, creamy skin feel. It works synergistically with other thickeners such as Cellulose Gum and Xanthan Gum. It also functions as an absorbent and mattifier.
