How to Make Natural Clay Soaps

Bentonite, Rhassoul, Kaolin, and Rose Clay Soaps

Clays used in soap
(From left) rose, rhassoul, kaolin and bentonite clays. David Fisher

You can use clay in soap making as a natural and gentle exfoliant, but you can also use it for skin care masks to remove oils and impurities from your skin, and its silkiness makes shaving easier, too. Clay is one great ingredient to use if you want to make special-purpose facial soaps.

Varieties of Clay

There are many different clays to choose from: kaolin, bentonite, rose clay, and rhassoul are among the most common. Each has a slightly different quality that might make you choose one over the other.

  • Kaolin: Kaolin is a mild, white, fluffy clay. It's good for light masks or scrubs and gives a silkiness and creaminess to soaps. It is good to use on dry or sensitive skin. It is used in facials, natural deodorants, and poultices.
  • Bentonite: Bentonite is highly absorbent and good for oily skin. It gives a slippery silkiness which makes it good a good additive in shaving soaps. It is actually not clay, but volcanic ash. It is found in only one place in the U.S., Fort Benton, Wyoming.
  • Rose clay: This is a general purpose clay used mostly for its lovely rose color, but also adds silkiness, slip, and absorbency to soaps. This clay cleanses and detoxifies, exfoliates dead skin cells, treats acne and sun damaged skin, and can increase blood circulation to the skin.
  • Rhassoul: This is a light brown clay that has used for its great ability to absorb oils and impurities from the skin and hair. It gives a lovely brown speckled color and is lightly exfoliating. This clay has been found to improve clarity and elasticity of the skin. It is also good for an oily complexion.

    Recipe for Clay Soap

    You can use the same recipe with the different clay ingredients. You can use 2 teaspoons of clay for every pound of oils. For a recipe that has about 53 ounces of oils, you will use a little over 2 tablespoons of clay in each of the batches. The oil composition is as follows:

    • 30 percent olive oil
    • 25 percent palm oil (you can substitute lard or tallow)
    • 25 percent coconut oil
    • 15 percent sunflower oil (you can substitute other liquid oils like canola, soybean, or almond)
    • 5 percent castor oil

    Methods for Mixing

    There are several methods to incorporate the clay into your soap mixture. Since it's an inert substance, you can add it at any time during the process, as long as it gets mixed in completely. If you were to dump the clay right into the pot, you would have to deal with a lot of lumps. It is best to start in small amounts and use a small whisk to mix well.

    • Add it directly to the lye-water: You can add the clay directly to the lye water. This works best with lighter clays like kaolin. Sometimes the heavier clays won't dissolve well in the water and will tend to clump. There's also the danger of splashing the lye when you're mixing. You might want to avoid this method for your first time.
    • Add it directly to the oils: In general, this is probably the method that works best, especially if you're not using the clay as a colorant to do any sort of swirl. Once your oils have all melted, just add the clay directly to the melted oils. Use your stick blender to make sure that it is completely incorporated. Look for clumps sitting on the bottom of the pot. Once the clay has been dispersed throughout the oil, just add your lye-water and proceed as you normally would.
    • Make a slurry of oil and clay: This is the method you would want to use if you wanted a more variegated or mottled color in your soap or to do a swirl. Once your oils have melted, add your lye-water solution. Just stir it gently until the lye and oils are lightly mixed together, but do not mix too much. Ladle out a cup or two of the lightly mixed raw soap and put it into a large measuring cup or bowl. Add the clay and mix well. Mix the rest of the soap in the pot until it is almost time to pour. Then you can stir the colored reserve of soap back into the pot and make a swirl. Or, you can pour the uncolored soap into the mold and layer or swirl the colored mix into it for an even more defined swirl. The challenge with this method is getting one large portion and one small portion of soap to trace at the same time and you need to work quickly.