What it is
Magnesium aluminum silicate is a naturally derived, refined smectite (clay) mineral that swells in water to form a gel-like network. In sunscreens it is widely used to thicken formulas, suspend insoluble particles such as mineral UV filters and pigments to prevent settling, and stabilize emulsions. It can also impart a smooth texture and help control oiliness through mild absorbency.
Safety & warnings
Inert and well tolerated topically, with very low irritation and sensitization potential; it is not a fragrance allergen and is not considered comedogenic in typical use.
Origin & sourcing
Natural mineral origin; mined as smectite clay and then purified and refined for cosmetic use.
Questions everyone asks
What does magnesium aluminum silicate do in sunscreen?
It thickens the formula and keeps mineral filters and pigments evenly suspended so they do not settle, while also helping stabilize the emulsion and smooth the texture.
Is magnesium aluminum silicate natural?
Yes, it is derived from a naturally occurring smectite clay that is mined and then purified and refined for use in cosmetics.