Residual kaolins usually form in high rainfall, subtropical or tropical climate because elevated temperatures and high rainfall increase the rate of breakdown of the primary minerals to clay minerals. These types of kaolins are closely related to the tectonic framework of a deposit and the alteration of parent rocks. Hydrothermal kaolins are formed from the hydrothermal alteration of alumina-silicate rocks. Kaolin deposits could be primary (hydrothermal, residual or mixed hydrothermal and residual deposits) or secondary (formed by erosion and transportation of clay particles and their deposition in lacustrine, paludal, deltaic and lagoonal environments) depending on their genesis. Boosting Cameroon’s and Nigeria’s economies will require new investments, and kaolin exploration and exploitation could be one of these. Chronic poverty stands at about 26% in Cameroon and 30.4% in Nigeria. Cameroon and Nigeria rank 158 and 170 on 189, respectively, on the Doing Business 2015 Report. Cameroon is a lower middle income country with a population of 23.3 million people, whereas Nigeria’s population is about 178.5 million people. Though these kaolin occurrences could be economically viable, most of them have not been studied. Twenty-five kaolin occurrences in Cameroon and 40 in Nigeria have been reported. Thus, the studied kaolins have the potential to contribute to improved economic development of these countries. Low MgO, CaO, Na 2O, K 2O and TiO 2 further position the kaolins for pharmaceutics, cosmetics, rubber and plastic applications. The current applications of kaolins from Cameroon and Nigeria include ceramics and manufacturing of bricks and tiles. The CIW versus CIA and ICV versus CIA plots showed that most of the kaolins clearly depicted extreme silicate weathering. Minerals in trace phases included smectite, anatase, muscovite, gibbsite, microcline, palygorskite and calcite. Kaolinite was the major phase, followed by quartz, illite and goethite as minor phases. Geochemical indices, including chemical index of alteration (CIA), chemical index of weathering (CIW) and the index of compositional variability (ICV) were computed and plotted on binary and ternary diagrams to determine the intensity of weathering of the kaolins and discriminate their different source rock types. Major oxides concentrations were subjected to factor analyses in interpreting their relationships. The geochemical characteristics of selected kaolins from Cameroon and Nigeria are presented, with an attempt to elucidate on their possible industrial applications by comparing them to world-known kaolin deposits.
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