We believe in complete transparency when it comes to dyes that will come into contact with your skin. That’s why we list all of the ingredients in every dye we sell; nothing is hidden as a “trade secret.” Most of our dyes are pigments produced from just three ingredients: a plant extract, alum (potassium aluminate sulfate), and washing soda (sodium carbonate). The alum combines with the plant dye to form a lake (a particle of color) and washing soda, a weak alkali, helps it to precipitate (undissolve). Ember Black is pure cosmetic-grade softwood charcoal, while our Maya Blue and Maya Green dyes are made from indigo and natural sepiolite clay. And that’s it. Just plant extracts, alum, washing soda, and clay.

In the USA, all cosmetics are strictly regulated by the FDA. Only colorants that have been evaluated and approved by the FDA are allowed to be used in cosmetic products. The FDA maintains a short list of approved colorants here. Many of the approved colorants are synthetic chemicals like D&C Red #21, which developed out of research on coal-tar colors in the 1800s. The only natural colorants currently on the list for cosmetics are carmine (the alum lake of cochineal) and annatto. Since the natural colorants we use (like madder lake and weld lake) have not been evaluated or approved by the FDA, they cannot be used in any FDA-regulated products. However, traditional cold process soap is not regulated by the FDA, so our natural dyes can be used in your cold process soap so long as it is not marketed with any medical claims (at which point it would be considered a medicinal product and would fall under the FDA colorant regulations).

Our soap dyes are made from insoluble pigments (color lakes and clays), while our textile dyes are mostly water-soluble extracts. Pigments have several advantages as soap colorants: they produce deep colors in cold process soap and they are less likely to bleed when washed. Also, textile dyes often contain organic plant matter (like tiny bits of root or bark) that don't cause any issues in a dye bath, but can cause unsightly speckles in a bar of soap. In contrast, our soap dyes will create even colors so long as they are dispersed completely into the soap batter.

Plant-based natural dyes are not as lightfast as synthetic dyes, and direct exposure to sunlight will eventually cause them to fade. This is usually a result of UV rays breaking down the bonds that hold together the color particle. Most of our soap dyes can withstand about a week of direct sunlight before noticeable fading occurs. However, the color will remain bright and vibrant for up to a year or more so long as the soaps are stored in a dark place or under artificial indoor light. For that reason, we recommend curing and storing soaps colored with natural dyes out of direct sunlight (and definitely not sitting on a window sill!). However, if you need a soap that never fades we recommend Maya Blue, which in theory can survive a few centuries of sunshine without losing any color.

We recommend dissolving most of our dyes in the lye water solution because the heat and alkalinity will help them to dissolve more evenly (exceptions include Maya Blue and Maya Green, which are clay-based pigments). However, you can always add the dyes at trace — for example if you want to divide up the batter and make each portion a different color. The main challenge will be getting the powder to fully disperse in the oils without any big clumps, which can cause dark speckles when the soap cures. If you need to add the dyes at trace, we recommend mixing them with a small amount of distilled water to make a thick slurry (you can reserve some water from the main recipe before adding lye, if you don’t want to worry about water discounts). This will give you a chance to break up any clumps; then you can add the slurry to the soap at trace and stick-blend it in. However, note that some dyes like Quebracho Brown can accelerate trace, so you may need to blend them in pretty quickly.

It is not necessary to force gel phase; none of our example soap bars went through gel phase. Forcing gel phase can result in slightly deeper colors in cold process soap (and sometimes different hues) but we have not tried it with our own dyes. However, if you give it a try, we'd love to hear about it! Our only caution is that you may get unexpected results with compound colors like Indigo Green, where gel phase can affect the indigo differently than the annatto.

All of our example bars were made with a three-oil base consisting of vegetable shortening, coconut oil, and olive oil. This has quickly become our favorite oil base because all the oils are available at the grocery store, and it produces a bar that hardens quickly without any additives. We have had the best results combining the lye solution and oil at 110F-120F. Since we usually use detailed silicone molds we usually pour at a fairly light trace, and leave for 48-72 hours before unmolding.