Ingredient dictionary

Stearalkonium Hectorite

Also listed as: Quaternium-18 Hectorite

A clay-based thickener made from hectorite clay treated with a fatty ammonium salt, used to thicken oil-based formulas. It is on the label of 10 products in our library. Checked against our library November 6, 2026.

What Stearalkonium Hectorite does

Thickens oils and water-free bases
Stops pigments and solids from settling
Builds a smooth, creamy texture

Stearalkonium hectorite starts with hectorite, a natural clay that is mined from the ground. The clay is treated with stearalkonium chloride, a fatty ammonium salt. That treatment changes the clay so it swells and thickens in oils and other water-free bases, where ordinary clays would not work well.

Formulators use it as a rheology modifier, meaning it controls how thick a product is and how it flows. It also keeps pigments and solids from settling in lip glosses and balms. On the skin, it feels smooth and slightly cushiony rather than sticky. It is a common choice when a product needs body without added water.

Good for

Suits water-free and oil-based products, such as lip glosses, balms, and some lotions, that need body.

Frequently asked questions

Is stearalkonium hectorite safe for babies?

It is used in some baby lotions to thicken the formula. Our checks do not flag it in any ingredient family. As with any product, a small patch test is a sensible step, especially for babies with sensitive skin. Ask a pediatrician about skin concerns.

Is it the same as bentonite?

Bentonite is a related clay, but a different one. Both belong to the smectite clay group, and both can be treated to work in oils. Hectorite is the source clay for this ingredient.