My goal is to get more out of my money by purchasing each individual homemade Monster Clay ingredient that I can sculpt my masks with, but I am trying to find the best substitute for the ball clay powder, as I plan to use this clay to make tin-cure and platinum-cure silicone molds, without making a clay that could cause cure inhibition. Could anyone be so kind to let me know what sulfur-free substitute I can use instead of ball clay powder?