I love the simplicity of those swirls--great job! What did you use for a black colorant? I've been wanting to try something like this, but am nervous about too much black colorant staining the lather and washcloth. I also have been wanting to try a version of Auntie Claire's "Ghost Swirl" and thought it would be neat to see what happens with the two lye concentrations in a black soap swirl. Your "half 'n half" swirl might show it off nicely.