The Potters Market Pottery Equipment
Ball clays are somewhat the opposite; of kaolin in their properties. They are higher in iron content, more fusible, much more plastic, and fine in particle size. Fire clay is not so well defined a type of clay as either ball clay or kaolin. The term "fire clay" refers to refractoriness or resistance to heat, and clays which vary widely in other properties may be called fire clays if they are