Self-hardening clay is smoother, finer and less sticky than traditional clay. Great for pinch, coil or slab techniques! No need for baking or firing. If carving is desired, allow to dry overnight, or until it reaches a leather-hard consistency. Once completely dry, it can be painted. Reconstitutes with water. 25 lb. package of white clay. AP Seal, non-toxic. Does not qualify for free shipping.