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Loess

Yellow loess soil

Well toleratedClay / mineralabsorbentbulking

No meaningful concern for most people; irritation is possible but rare.

Also written as: Hwangto · Yellow Earth · Yellow Soil

What it is

Loess is a loose, silt-sized mineral sediment deposited by wind, rich in quartz with some clay minerals and iron oxides that give it a yellow-brown colour. It has a long history in Korean and Chinese folk skincare as hwangto or yellow earth, and appears in Korean wash-off masks. In a formula it behaves as a mild absorbent and bulking powder rather than a strongly swelling clay.

How it shows up on a label

Common in Korean wash-off masks marketed on the hwangto tradition.

What it does well

  • Mild oil absorption with less tightening than bentonite

    Its silt-heavy, low-swelling structure means it mattifies without the pull of a smectite clay. The long record of traditional use is not matched by controlled clinical evidence.

    Traditional use

Worth knowing

  • Composition varies with the deposit

    Loess is defined by how it was deposited rather than by a fixed mineralogy, so quartz content and trace metals differ between sources. Cosmetic-grade material is purified and tested, but this is an ingredient where the supplier matters.

    Matters most toBuyers of unrefined or DIY 'yellow earth' powders.

Where the EU stands

Class entry may apply

Loess is named in none of the annexes of the Cosmetics Regulation. That is no longer enough on its own to conclude there is no limit: Regulation (EU) 2026/909 added Annex III entry 381, a class entry over aluminium-containing ingredients, which from 1 January 2027 caps aluminium in the finished product at 0.89% (as Al) for face and body rinse-off products and 10.59% (as Al) for face leave-on, and which applies by composition rather than by name. Loess is a wind-blown sediment rather than a single mineral - mostly quartz, with clay minerals and iron oxides whose proportions vary from deposit to deposit - so how much aluminium a given grade carries is not fixed, and none of the entries entry 381 excepts names it. No concentration limit attaches to loess itself, and the general safety assessment every cosmetic product must pass before sale applies as it always did.

Regulation (EC) No 1223/2009 - no annex entry; Annex III entry 381 (aluminium-containing ingredients), added by Regulation (EU) 2026/909 and renumbered from 379 by the corrigendum at OJ L, 2026/90354, 5.5.2026 · source ↗

Masks that contain Loess