New Mexico Clay - Ironstone (Cone 5/6) Ironstone Black Clay is a newly improved black clay with a high iron content, which makes it magnetically reactive and visually striking. Fired to cone 6, it features a medium texture that is easy to work with and won't stain your hands. The iron-rich body influences glaze reactions, potentially causing speckling and unique surface effects. Due to its wide range of reactions to temperature, glazes, and firing atmospheres, extensive testing is recommended to fully understand its behavior and achieve the desired results. Ideal for experimental and creative projects, IRONSTONE offers both bold aesthetics and versatility.