China clay or Kaolin is a natural mineral found in partly decompo-sed granite, an igneous feldsparic rock. Chemically, china clay is a hydrated aluminium silicate containing Al2O3.2SiO2.2H2O.
The chemical compound silica, also known as silicon dioxide, is the oxide of silicon, chemical formula SiO2. Siliceous is an adjective meaning "referring to silica".
The carbonate mineral calcite is a calcium carbonate corresponding to the formula CaCO3 and is one of the most widely distributed minerals on the Earth's surface.
