What is clay?

Potter's clay refers to viscous earth that serves as the material for pottery. It possesses properties suitable for shaping and firing, and is widely used as the primary raw material for ceramics.

The raw material for porcelain produced in the Hizen region (Arita, Imari, Hasami, etc.) is not "clay" but rather powder from a stone called pottery stone.

The quarried pottery stone is crushed, ground into powder, and refined. This refined powder is then kneaded in a pug mill to create soft, pliable clay, making it ready for shaping before moving on to the forming process.

For porcelain, throwing on a potter's wheel is not very common and is considered a very rare technique. Instead, the prevalent method is "slip casting." This method involves pouring liquid potter's clay (slip) into a plaster mold to take its shape, and it is widely used as an efficient manufacturing technique with excellent mass productivity.