The composition of kaolinite is Al4[Si4O10](OH)8, and it is an important mineral ore for making ceramics. It gets its name because it was first discovered in Gaoling (Kaolin) Village in Jingde Town, Jiangxi Province. Kaolinite belongs to the monoclinic crystal system and appears as small pseudohexagonal or scale-like plates or as blocky, dense, earthy or clayey aggregates. It is white, colourless, light yellow, light brown, light red or light blue with white streaks. It also has transparent to translucent diaphaneity, a pearly to dark earthy lustre, a specific gravity of 2.6–2.63, a Mohs hardness of 2–2.5, and uneven fractures. It is mainly found in weathered feldspar and other alumina-rich silicate minerals, especially in hot and humid areas where the feldspar in granite can weather into loose white kaolin clay.