What it is
Montmorillonite is a soft phyllosilicate clay mineral and the main component of bentonite, formed from weathered volcanic ash. Its layered structure swells with water and absorbs oils, which makes it useful for thickening formulas, mattifying skin, and stabilizing emulsions and suspensions. In mineral sunscreens it can help structure the product and improve the spread and suspension of UV-filter powders.
Safety & warnings
Montmorillonite clay is generally considered inert and well tolerated on skin and is not a fragrance allergen. As an oil-absorbing mineral it is non-comedogenic, though it can feel drying for some users at high levels.
Origin & sourcing
Natural mineral clay, mined from geological deposits derived from volcanic ash.
Questions everyone asks
What is montmorillonite used for in sunscreen?
It is a clay mineral that absorbs oil, thickens the formula, and helps suspend and spread mineral UV filters evenly.
Is montmorillonite natural?
Yes. It is a naturally occurring clay mineral mined from deposits and is the main component of bentonite.