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Magnesium Aluminum Silicate

What Magnesium Aluminum Silicate is & what it does

A mineral clay used to thicken, stabilize, and suspend particles evenly, giving formulas a smooth, creamy body. It also adds a soft, matte feel.

What is Magnesium Aluminum Silicate and what does it do in sunscreen?

Magnesium Aluminum Silicate is a refined mineral clay used to thicken and stabilize a formula. It suspends particles like mineral UV filters evenly so they do not settle, and it gives lotions a smooth, creamy body. It also lends a soft, slightly matte feel.

Is Magnesium Aluminum Silicate safe?

Yes. It is a long-used, well-tolerated mineral thickener that works on the surface and is not absorbed into the skin. It is inert and non-reactive, which is why it appears in many creams and lotions. It is not a known irritant or sensitizer for most people.

Does Magnesium Aluminum Silicate clog pores?

Generally no. It is an inert mineral clay used in small amounts to give texture, not a heavy oil or wax, so it is considered low risk for clogging pores. Its soft, matte feel can actually help oily skin. Clogging usually traces back to richer emollients in a formula instead.

Is Magnesium Aluminum Silicate the same as aluminum metal?

No. Despite the name, it is a stable mineral silicate (a clay), not free aluminum metal and not an antiperspirant aluminum salt. The aluminum is locked into an inert mineral structure that sits on the skin's surface. It is there purely to thicken and stabilize the product.

Is Magnesium Aluminum Silicate natural?

Largely yes. It is derived from naturally occurring clay minerals that are purified and refined for cosmetic use. The processing standardizes its quality, but the base material is a mineral from the earth rather than a lab-built molecule.

Sunscreens with Magnesium Aluminum Silicate

We rate 152 sunscreens that contain it, showing the top 10 by overall score:

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