Last month I found myself at Maria Hurley’s Mayan Clay Spa in Tulum, laying inside a jungle bungalow, completely covered in clay. Not your standard “part of the facial' clay mask. No—a very kind masseuse applied layer upon layer to my face, body, and hair until I was nice and crusty. Then she led me to the ocean, where I tried my best to rinse off. Eventually, I turned to the outdoor shower to get rid of the rest of it.

At first dollop of clay, it's tempting to think, is this too much of a good thing? But after washing off the clay—which feels sort of like peeling the shell off of a hard-boiled egg if the egg is your body—my legs were smoother and my face was noticeably calmer following some recent acne flareups. It's less of an exfoliating experience and more like molting. Weird, but also gentle and soft.

Initially, I was under the impression that the clay treatment, as decadent as it was, only pertained to my skin. Not so, Maria told me. “The Mayan people believe that the first man was actually full of clay,” she said. Originally from New Zealand, Maria began looking into new ways to incorporate clay into her routine after growing up with it as a topical solution. “If we had mosquito bites, cuts, or abrasions, we always put clay on it because that’s part of the culture. But a lot of people also say that because clay is formed in the river and is left out in the sunlight, wind, and rain for thousands of years, it absorbs all of those properties of nature. It takes on the energy, so when you look at it as a substance, you can say that it's the sum of the pull of nature’s energy.”

That pull can be alluring—by now Shailene Woodley using and ingesting her own clay toothpaste is fairly old news. But once you've cleaned your pores (and teeth) thoroughly, what's left? Plenty, according to Maria, who's used clay treatments on everything from rashes to stomach aches. Read below for her take:

To combat eczema:

“Clay can be used for rashes, mosquito bites, and any dermatological problems on the skin because it helps decrease inflammation. Applying the clay and letting it dry absorbs the toxins,”

To feed skin some nutrients:

“I always recommend that the first time you use clay as a facial mask, wet it down slightly as it begins to dry. That way, skin absorbs more minerals from the clay.”

To darken hair and condition:

“It can be used as a very light hair conditioning treatment—people often buy it because it helps to darken their color. Don’t use a lot—it shouldn’t be a thick application, but it helps neutralize the effects that conditioners, shampoos, and treatments have had. Then you can make a hydrating treatment on top of wet hair. You could mix up a milky solution of honey with a bit of clay and water and use that as a rinse to help soften the clay mask underneath,”

To exfoliate gently:

“Wet your face, apply your clay, and just begin to lightly massage the clay in for about two or three minutes. Then, wash it off, and you've got just enough of a soft, natural exfoliation. Apply your night cream right after, and it'll absorb quickly. I think doing this at night is better because that’s when the face is relaxed,”

To de-puff eyes:

“Some people have very inflamed under-eye bags. Moisten the under-eye area and apply quite a thick application of clay around the eyes. Leave it on for at least 20 minutes, then wash it off. Doing this even a couple of times a week helps decrease puffiness because clay will absorb excess fluid.”

To moisturize skin:

'Clay can be mixed with honey or chamomile tea to make a very lovely hydrating mask for the skin. It's especially nice around the eye area, but probably do without the honey then—just the chamomile tea for the eyes is nice.”

To eliminate acne:

“When skin has acne, it's an indication that you shouldn’t massage it. Just leave it alone and put clay on it every day to soothe,”

To relieve stomach pain:

“If someone has an upset stomach, a massage might be too much, but you can apply a thick layer of clay and just let it sit. Leave it on, and it will absorb the gas and the liquid and calm your stomach ache. When you’re treating individual organs, it should just be applied to that organ. For example, over the kidneys or over the liver. Apply clay in one area at least half-a-centimeter thick.”

To alleviate back pain:

“It can be used just over the spine to calm down nerves. When people are going through a very stressful time or even menopause or depression, apply a thick layer of clay to the spine and relax the central nervous system,”

Got any other ideas on how I can use these leftover jars of clay? Ceramics are off the table.

—Claire Knebl

Photos courtesy of the author. For more on clay, read The Clay Toothpaste Roundtable.