Soap? The walnut powder can be used as a colorant and I think someone mentioned it was slightly exfoliating. Tussah silk can be dissolved in the lye solution to add a silky feel to the lather. Peppermint leaves allegedly produces a green-yellowish type of color but again I think someone mentioned the peppermint leaves were more of a rusty orange color. Please don't hold me to that because I might be confusing it with another botanical.