Ball Clay

Ball clays are very plastic and much finer-grained than kaolins. They are easily slaked in water when dry. The fine particle size also makes them impermeable to the passage of water for good plasticity. Ball clays are used in ceramic bodies (porcelains, stoneware, earthenware, casting slips, pressing bodies) because of their plastic nature combined with high firing temperatures. Ball clays have very high dry shrinkage combined with high green strength. 

Ball clays would be ideal ceramic materials. However, in practical terms, they are employed to achieve the desired plasticity but are minimized to reduce the detrimental effect on fired whiteness and drying properties.

Ball clay is a binding agent and helps to enhance the plasticity, workability, and strength of a pre-fired ceramic body. Some are highly effective for their fluid and casting properties, particularly in the manufacture of sanitaryware.