I learned something new recently after teaching a class at The Nova Studio. (That’s the best part of teaching: learning along the way.)
While I’ve tried out lots of natural ingredients to color cold process soap (ahem, I even wrote an eBook on the subject), I haven’t done a lot of coloring with more than one color in bar at the same time. But in this class, I decided to demonstrate a vertical layer with a swirl using turmeric and madder root to color each half of the batch.
So wasn’t it a lovely surprise to discover that turmeric bleeds in soap?! That is to say that the color doesn’t stay where you place it in the bar: it migrates and blends into the neighboring soap making the border between the two colors fuzzy.
Compare this result with other bars I’ve made using the same technique but using other colorants that don’t bleed into each other. See how crisp the borders are? This soap was colored with micas. Very different.
I suspect that it’s the turmeric that’s migrating because I have made a two-colored soap with madder root before. In that case the other part was colored with clay and there was no color migration. But it could be that turmeric and madder root together act differently than clay and madder root. More testing is in order!
Have you ever discovered something about soapmaking by chance?