Clay masks and facial products are all the rage, but they?re hardly a new phenomenon. Knowledge of the healing powers of clay can be found in the ancient world and in the far reaches of space. The Roman naturalist Pliny the Elder devoted an entire chapter of his Natural History to clay, while American astronauts ingested clay to stave off accelerated osteoporosis from zero-gravity space flights. Used topically, clay has a long history in skin care. It?s a particularly appealing ingredient in the natural products industry—after all, what could be more natural than clay?

There are many types of clay, but they all share similarities on a molecular level and in terms of their healing properties. ?Clays are excellent for purification,? says Jennifer Barckley, communication and public relations manager for Weleda USA, based in Congers, N.Y. The company uses a clay called smectite in its pink toothpaste, both for its gentle abrasive action and anti-inflammatory properties.

?The main benefit of clays is their absorptive property,? says Laura Genoway, products consultant for Avalon Organics in Petaluma, Calif. ?They tend to draw out impurities, including dirt and excess oils.? Alba?s deep-sea facial mask contains kaolin clay, a white clay commonly found in facial care products. It is the least drying of common clays and is suited for a variety of skin types. ?It?s the most versatile of the clays, as well as the most widely available,? Genoway says. ?Illite clays, which are often green, have a molecular structure that causes them to absorb a lot more moisture than white clays, so they?re not as good for normal to dry skin.?

Clays can also help exfoliate in two ways—by pulling dead skin cells away from the top layer of skin and by scrubbing the skin with fine particles. ?We use kaolin clay in a lot of our exfoliants,? says Victoria Palmisano, brand manager for EO Products in Corte Madera, Calif. ?Polish is our gentle exfoliant with clay, targeted for delicate skin, but we also use it in our body polish and foot scrub.?

?Another reason [kaolin clay?s] great in skin care products is its ability to stimulate circulation,? Palmisano says. ?Clay has a drawing action, both physically and through a kind of magnetism because of potassium ions in its structure,? says Kathy White, an ingredients information specialist for Dr. Hauschka Skin Care in Hatfield, Mass. ?This property can be likened to the use of magnets in healing. For skin care, it?s an ideal ingredient, because of its ability to draw out impurities and speed healing, especially for blemished or acne-prone skin.?

But toxins and impurities are found in and on all skin, not just skin that is obviously damaged. ?The skin is the biggest organ in the body and has a key role in eliminating toxins. Clay can both draw toxins out and soak them up from the surface of the skin,? says Genoway.

Dr. Hauschka uses two earth-based ingredients in its products. The company includes a German clay known as ?healing earth? in its cleansing clay mask—not a true clay, but rather a substance called loess, a very fine silt—and white bentonite clay, which is of volcanic origin, in its cleansing milk.

Another company offering clay-based products is Druide, based in Pointe-Clare, Quebec. While most companies use dried clays, which are then reconstituted for use in personal care products, Druide works with a unique deposit of fresh clay from a location near the St. Lawrence River. ?A meteorite created the hole where water collected to create a system of lakes,? says Kevin Alexander, director of the U.S. market for Druide. ?It also left unique chemical residues that created a special kind of clay.?

Alexander believes that because clay is an entirely natural substance, the skin has a special affinity with it. ?When people use clay, the skin accepts it, has a relationship with it,? he says. ?Because this clay is not dried, it still contains micro-algae that feed the skin. The skin actually draws in these microbacteria, and they penetrate to the bottom layer of the skin, pushing out toxins from the root. It takes more time to show its effectiveness, but it?s a richer, deeper effect than other clays, which only nourish the top layer of skin.?

Druide is the first company to base a commercial product line on this particular type of clay, called Manicouagen marine clay. It has already created a purity shampoo for oily hair and scalps and a purifying bar soap, and will have a pure clay facial mask by the end of the year.

So, what makes a clay a clay? ?Clays by strict definition are primarily aluminum silicate, derived from sandstone and such,? says Bruce Akers, director of research and development for EO Products. ?Aluminum silicate is the base molecule, but other soils mixed in create different types of clays. Green clays tend to have more copper, red clays more iron in the soil, and black clays can contain iron or organic matter.?

Some companies market clay-based body and facial products as ?muds,? but Akers says true muds are most likely to be found in spas, where they can be freshly prepared. ?Muds are basically a mixture of earth and water,? he says. ?They usually have a much higher organic content and are more prone to bacterial growth. Clays are much more homogenous.?

All clay, Akers says, works on the outer layer of skin, exfoliating and balancing the skin?s oils. ?It pretty much sits on the top layer, which is dead,? he says. ?But you want to keep that dead skin looking good, just like dead hair and other dead parts of your body. Your skin is always flaking and falling off, but you want to keep it balanced so it doesn?t fall off in big chunks.?

Though aluminum silicate is the primary component of clay, comprising 50 percent to 75 percent of its mass, clay also contains varying amounts of other minerals and salts, including magnesium, calcium, potassium, dolomite, manganese, phosphorous, copper, iron, sodium and titanium. Each of these constituents can affect the texture, color and specific properties of a clay.

But most customers are neither chemists nor geologists. They want clay products because they work. Their ability to draw toxins, balance the skin, absorb excess oil and moisture, and gently exfoliate make them an ancient remedy with a bright future.

Mitchell Clute is a freelance writer in Crestone, Colo.

Natural Foods Merchandiser volume XXVI/number 3/p. 86, 88