Clay is one of the easiest soap making supplies for adding natural color. Every clay here is vegan, palm-free, and paraben-free. Each one has an indefinite shelf life when stored properly.
Choosing the Right Clay Powder for Soap Making
All five clays are recommended for cold process, melt and pour, and bath bombs. Their color will not bleed between layers.
- Kaolin Clay: This is pure kaolin. It is the only clay here sold in a 55-pound bag for production runs.
- Rose Clay: This is kaolin blended with iron oxide. The iron oxide gives your bars their natural pink color.
- French Green Clay: This clay is montmorillonite. It brings a natural green color to soap.
- Bentonite Clay: This is pure bentonite. It soaks up more water than the others.
- Sea Clay: This is hydrous alumina silicate. It adds a soft natural color to your bars.
For brighter shades, layer clay with micas colorants in the same batch.
None of these clays are eye-safe or lip-safe.
How Much Clay to Add to Homemade Soap
We recommend starting at 1 teaspoon of clay per pound of soap. Adding the dry clay to your batter will absorb some of the liquid; this can cause clumps and can thicken cold process soap fast.
- Cold process: Mix 1 teaspoon of clay with 1 tablespoon of distilled water. Add 1 teaspoon of the dispersed clay at a time.
- Melt and pour: Mix 1 teaspoon of clay with 1 tablespoon of 99% isopropyl alcohol. Add 0.5 teaspoon of the dispersed clay at a time.
- Scrubs and bath bombs: Start with about 0.25 teaspoon per pound. Blend the clay into your dry ingredients first.
Bentonite will not disperse in oil. Stirred into oils dry, it leaves dark specks that look like black pepper.
Hydrate it in water a few hours ahead or the night before. Whisk in small splashes until the slurry turns smooth and creamy.
Scaling Colored Clay for Production Batches
Make a 1-pound test batch first to preview the color. Then multiply your batch weight in pounds by 1 teaspoon. A 10-pound batch needs about 10 teaspoons of clay.
Weigh one level teaspoon once for consistent color in every batch.
Every clay has a 1-ounce test size option. Rose, sea, French green, and bentonite clay also have 16-ounce bags to choose from. Kaolin clay has a 2-pound and 55-pound option.
What happens if I add too much clay to cold process soap?
Too much clay can leave bars very hard and crumbly. Grate the batch into a fresh batch of soap, then return to 1 teaspoon per pound next time.
Should the water I use to mix clay come out of my recipe’s total water?
Yes, take it from the water your recipe already calls for, so a 10-ounce recipe still uses only 10 ounces. Note how much goes into the slurry, then mix your lye with what remains. Never go under a 1: 1 ratio of lye to water when dissolving your lye.
Will clay speed up trace in cold process soap?
Clay can thicken batter quickly, especially when it goes in dry. Disperse it in water first and stick-blend in short bursts to keep a pourable trace.
Which clay works best in shaving soap?
Bentonite gives the most slip, which helps a razor glide across the lather. Start at 1 teaspoon per pound and compare it against a clay-free test bar.