Kaolin or china clay is a natural mineral found in partly decompo-sed granite, an igneous feldsparic rock. Chemically, kaolin is a hydrated aluminium silicate containing Al2O3.2SiO2.2H2O. It is one of the most abundantly available clay in the Earth's crust. It is a soft, earthy, usually white to off white and sometimes reddish in colour, produced by the chemical weathering of aluminium silicate minerals like feldspar.
