It is a layered silicate mineral, with one tetrahedral sheet linked through oxygen atoms to one octahedral sheet of alumina octahedral.
China clay or Kaolin is a natural mineral found in partly decomposed granite, an igneous feldsparic rock. Chemically, kaolin is a hydrated aluminium silicate containing Al2O3.2SiO2.2H2O.
Kaolin was first discovered in the mountainous province of Kiangsi, China in A.D. 500. The word “kaolin” derives from the Chinese character ‘kao lin’ which means high ridge. It was first used by the Chinese to make high quality porcelain.
• It fills out the rubber to increase the volume
• Strength and rigidity can be improved
• Good oil adsorption
• High cost: performance ratio
• High level of reinforcement at a low cost
• High tear strength
• It has low moisture content (Max 0.2 %)
• Fine particle size with very low grit levels
• High surface area
• It is a naturally-occurring clay mineral which is inert and harmless, even if consumed
• Water-washed kaolin is soft and non-abrasive
• Pumps and machinery are not affected
• Consistent colour