Kaolin is formed by a group of hydrated aluminum silicates, mainly kaolinite and haloisite. When found in white color it has higher added value due to low iron oxide content, but depending on the impurities present it may have dark color.

In the ceramic industry, its main functions are to contribute to the white burn color, to provide dimensional stability, to reduce the pyroplasticity index and to act as a suspending agent in glazes and engobes.