I just experimented with different botanicals using Indigo root as the "blue". Top left to right. (purple)Indigo/madder root powder, (green) indigo/gold brazilian clay. Bottom left to right. (green) indigo/annatto oil, (purple) indigo/himalayan rhubarb root oil. I unmolded when the soap was a little too soft. I was too impatient. I think the colors will stay true and not morph. Fingers crossed