Making Natural Clay Soap Samplers

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

As I was reorganizing my soap making space recently, I got out my jars of clay...not the kind you make cups or pots out of, but the kind you make soap with. I've used clays in shaving soap recipes but clay is a wonderful additive for everyday soap too. The first time I made soap with clay, I couldn't pick just one, though, I ended up making four batches using kaolin, bentonite rose and rhassoul clays.

I cut the normal size bars in four pieces, and then assembled a full "bar" of the four different varieties.
The four clays I used were:

  • Kaolin - a mild, white, fluffy clay. It's good for light masks or scrubs and gives a silkiness and creaminess to soaps.
  • Bentonite - a light green clay, it is highly absorbent and good for oily skin. It gives a slippery silkiness which makes it good in shaving soaps.
  • Rose clay - a general purpose medium weight clay used mostly for its lovely rose color, but also adds silkiness, slip, and absorbency to soaps.
  • Rhassoul - 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.

To allow people to compare the differences between the clays, I used the same recipe for all four batches:

  • 30% Olive Oil
  • 25% Palm Oil (you can substitute lard or tallow as well)
  • 25% Coconut Oil
  • 15% Sunflower Oil (you can substitute other liquid oils like canola, soybean, or almond too)
  • 5% Castor Oil

I used about 2 teaspoons of clay for every pound of oils. My recipe had about 53 ounces of oils in it, so I ended up with a little over 2 tablespoons of clay in each of the batches.

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. You can:

  1. 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. This is my least favorite method.
  2. Add it directly to the oils.I think this method 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/dispersed. Look for clumps sitting on the bottom of the pot. Once the clay has all been dispersed in the oils, just add your lye-water and proceed as you normally would. This is the easiest method (and the method I used in these batches) but the clay is dispersed evenly throughout the whole batch for an even color.
  3. 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 - don't 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's 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 - you need to work quickly.