Vivid hues can be achieved with all natural colorants. In fact, you can create just about every color in the rainbow! For this Natural Rainbow Cold Process Soap, I used six colorants in the Natural Colorants Sampler Pack to create layers of red, orange, yellow, green, blue and purple. This soap is fragranced with a combination of lime and lemongrass essential oil for a scent that’s as bright as the layers.
For this project, I added the majority of the colorants directly to the soap batter. The one exception was annatto seed. I made an infusion with the seeds and used the infused oils to create the orange and yellow hues. To help the colors really pop, I recommend soaping at slightly higher temperatures (around 120-130° F) to help the soap go through a complete gel phase. I also recommend insulating the soap, and placing it on a heating pad if your room temperature is on the cooler side. Gel phase really helps natural colors pop! Click here to read more about gel phase, and when to insulate your soap.
The drawback of natural colorants is they do tend to fade with time. These photos were taken about one week after cutting. The colors have faded slightly since then, but are still quite vivid. To help prevent the colors from fading, be sure to keep your bars out of direct sunlight. If you’ve never used natural colorants before, check out the Sunday Night Spotlight on natural colorants here. My new book, Pure Soapmaking, is also full of information on natural colorants, including how to infuse them and what they look like after they fade.
UPDATE 7/6/2016: Below is a photo of the soap about 5 months after unmolding. As you can see, some of the colors have faded slightly. Specifically, the green shade has faded the most. This soap was stored in a dry, cool and dark place. Most of the colors still look quite vivid!