According to the geological site of rocks, there are two types of clays.
Residential Clay is formed at the site of parent rock. It is less common than sedimentary clay, but generally whiter and purer. Most porcelain and kaolin are residential clay. Residential clay contains larger-size particles since it does not go through the storing and grinding of transportation. Therefore, it is less plastic than sedimentary clay.
Sedimentary Clay has been moved far from the original site by action of wind or water. The transportation made the clay particles finer, and therefore sedimentary clay are more plastic than residential clay. Ball clay, stoneware clay, fireclay, earthenware clay ..etc are sedimentary clay.