Kaolinite is formed by weathering or hydrothermal alteration of aluminosilicate minerals. Thus, rocks rich in feldspar commonly weather to kaolinite. In order to form, ions like Na, K, Ca, Mg, and Fe must first be leached away by the weathering or alteration process.
What kind of rock is kaolinite found in?
2.2.
Kaolin has, in places, been derived from well-stratified argillaceous sedimentary rocks with more than 50% of their grains of a particle size of less than 0.062 mm and strongly enriched in phyllosilicates.
How is kaolin manufactured?
Kaolin is extracted from the ground by surface working (open cast method). It is tradtionally liberated from its host rock by powerful water jets (monitors) and the resultant slurry undergoes settlement and separation to remove the quartz, mica and unaltered feldspar.