Coarse-grained sand, semi-weathered and decomposed granite, composed mainly of feldspar and quartz, with mica, kaolin, and other minerals. It is white, light gray or light brown in color. It is produced in large quantities in various parts of Aichi and Gifu Prefectures, and is an important raw material for ceramics. As a raw material for ceramics, it is relatively rich in feldspar and contains little biotite, but recently it is increasingly being refined by hydrochloric acid and other chemical processes to remove iron from the metal.
