Rhassoul Clay

The science

Rhassoul (ghassoul) is a rare volcanic clay from the Atlas Mountains of Morocco, used in hammam rituals for over 1,400 years.

• Ion exchange — the clay carries a strong negative charge, so positively charged sebum and grime are drawn out without surfactants.
• Mineral-rich — about 57% silica and 25% magnesium, plus iron, potassium and calcium.
• Swelling capacity — absorbs up to three times its weight in water and sebum. Harrabi et al., Applied Clay Science 2009, documented its superior ion exchange capacity.

Best for

Oily scalps and oily flaking, deep cleansing of product and hard-water buildup, and curly or coily hair that wants definition and shine.