Kaolin deposits Mineralogical geochemical and isotopic properties

Hydrothermal alteration processes form clay minerals. Argillic alteration constitute exploration objectives for epithermal and porphyry-type deposits. Argillic alteration exhibits lateral and down zonation that can be divided into mineral assemblages. These assemblages were as follows: silicified zone (silica cap) quartz+ kaolin minerals + alunite zone and K-feldspar + illite + montmorillonite zone.On the basis of geochemical and mineralogical characteristics the hydrothermal fluids that formed the kaolin deposits were acidic.