You know that running joke in My Big Fat Greek Wedding where the dad uses Windex for everything? That’s how I think about St. Meto’s Mother Clay. It’s not literally a cure-all—but as far as scalp and hair resets go, it comes remarkably close, no matter what kind of hair you have.

At its core is volcanic-ash bentonite clay, an ingredient rich in minerals including calcium, magnesium, and silica. In practice, that means it absorbs excess oil, pulls away buildup from styling products and hard water, and helps rebalance the scalp without stripping it raw. Clay has always been a harmonizer in skincare—think masks and cleansers—and in this formulation, it plays the same role for your head. The texture is plush and velvety, almost marshmallow-like, with a cushioning slip that feels nourishing rather than harsh. As you work it through damp hair, it thickens slightly by design, building body while it detoxes.

The payoff is impressively democratic. Fine hair gets a shot of volume. Thick or coarse hair becomes more controlled without needing grease or gel. Frizz settles. Shine improves—not from added gloss, but because the residue that was limiting your hair’s potential is gone. It even works if your hair is very, very short: On a buzz cut or bald scalp, it functions as a purifying, toning scalp treatment that keeps flakes and irritation at bay.

Mother Clay is the hero product from founder Kristen Shaw, a celebrity groomer whose client roster includes Jonathan Bailey, Seth Rogen, David Corenswet, and Brandon Sklenar. She developed it for the realities of Hollywood: long days, heat, heavy product, unforgiving cameras. The philosophy is simple—hair should look healthy before styling even begins. Some of her clients even use it lightly as a finishing or detailing product for a dry, voluminous effect, though it’s primarily formulated as a scalp treatment.

It’s especially good on color-treated or over-processed hair. By removing mineral imbalance and residue, it can brighten blondes, soften straw-like ends, and restore clarity to grays that have picked up a yellow cast over time.

Usage is straightforward: apply the mask to your hair when it’s damp and let it sit and work for about 10 minutes. Then, all you have to do is rinse it out. One tube equals one full treatment for longer hair; shorter styles can stretch it across multiple uses. Most people use it monthly, though very oily or damaged hair may benefit from twice-a-month sessions.

The result is softer, bouncier, more defined hair—and a scalp that feels genuinely reset. Not quite Windex. But close.