Kaolin is a clay rock and part of the group of industrial minerals with the chemical composition (Al2Si205 (OH)4.
It is a layered silicate mineral with one tetrahedral sheet linked through oxygen atoms to one octahedral sheet alumina i.e. structurally composed of silicate sheet (Si2O5) bonded to aluminum oxide/hydroxide layer Al2 (OH)4 called gibbsite layers and repeating layer of the mineral are hydrogen bonded together. (Rost, 1992; Bish, 1993; Klein and Kuribut, 1993; Slivka, 2002).
Kaolin is a plastic raw material, particular consisting of clay mineral kaolinite. In systematic mineralogy, Kaolin ranks among phyllosilicates, which are stratified clay minerals formed by a network of tetrahedral and octahedral layers. Phyllosillicates are classified into the main groups according to the type of layers, inter-layer contents, charge of the layers and chemical formulas. Besides kaolinite groups, serpentine, halloysite, pyrofylite, mica and montmorillonite groups also ranks among phylllosillicates. Group of kaolinites includes di-octahedral mineral with two layers and one silica (SiO4) tetrahedral layer and one aluminum (Al2(OH)4) octahedral layer. The layers are bondecd together by sharing oxygen anion between Al and Si together, these two layers are called platelets (Pauk,et al.,1962; Stejskal, 1971., Duda et al., and Hurlbut, 1993).