Kaolin
Kaolin , noun
[Chin. kao-ling.]
(Mineralogy) A very pure white clay, ordinarily in the form of an impalpable powder, and used to form the paste of porcelain; China clay; porcelain clay. It is chiefly derived from the decomposition of common feldspar.
The name is now applied to all porcelain clays which endure the fire without discoloration.
Also: Kaoline