Gibbsite is not stable in presence of quartz and it will be changed into kaolinite minerals, so gibbsite has formed after the deposition and we can call it neo-formation gibbsite. Now, the main question is about gibbsite formation in the middle of kaolin series. Due to the pH of leaching, a dissolution of Al2O3 or SiO2 can occur (podzol or laterite profile) The first theory tries to describe this with podzol profiles: it assumes the leaching of silica from minerals and accordingly the gibbsite formation from leached kaolin. We thus should find the hyper-aluminous materials, containing gibbsite in the lower series of kaolin. On the other hand, a second theory proposes the procedure of aluminium leaching in a very acid medium, in deposited organic materials (lignite) with clay. The organic materials can accelerate the solubilization and transportation of aluminium ions with intervention of organic complex. proposed the following scenarios for this dissolved aluminium.