Kaolin is a non-metallic mineral, mainly composed of kaolinite, halloysite, hydromica, illite, montmorillonite and quartz, feldspar and other minerals, often mixed with pyrite, limonite, anatase, quartz, chalcedony, alum, etc.
Kaolin is widely used in ceramics, paper, rubber, plastics and refractory industries due to its excellent processabilities such as plasticity, cohesiveness, sinterability and fire resistance.
There are three main types of the genesis of kaolin deposits: weathering, sedimentary and hydrothermal alterations. The processing of kaolin ore depends on the nature of the ore and the end-use of the product. There are two processes used in industrial production: the dry process and wet process. Usually, hard kaolin is produced by the dry process, and soft kaolin is produced by a wet process.