Hawthorn Fireclay is a refractory, buff colored fireclay. It is a very popular material that is used in many clay recipes. Hawthorne has an incredibly high plasticity and a high temperature, vitrifying around cone 8-10 (with the small addition of a feldspar) and shrinking about 12% at cone 10.Information gathered from Digitalfire Ceramic MaterialsDatabase.50# bag; brown bag, blue textMinerals and 35 Mesh Bond