CHARACTERIZATION OF CLAYS

This study represents a comparative mineralogical and geochemical evaluation of clay deposits from Igo and Okhoro, located within the Benin Formation of Southern Nigeria, with the aim of determining their industrial suitability and economic potential. Field observations revealed that the Igo clay occurs as reddish to brownish lateritic clay interbedded with sands, whereas the khoro clay is predominantly light grey with brown patches and is more quartz-rich. X-ray Fluorescence (XRF) analysis of the Igo samples shows high concentrations of silica (SiO₂: with mean value 68.57%) and alumina (Al₂O₃: with mean value 22.59%), with relatively low levels of fluxing oxides. In contrast, the Okhoro samples contain lower silica (mean 59.25%), comparable alumina (mean 21.86%), but noticeably higher iron oxide (Fe₂O₃: up to 7.34%) Trace element concentrations in both locations were generally low, indicating minimal impurity influence on industrial applications. The X-ray Diffraction (XRD) data reveal that the Igo clays are dominated by kaolinite (24.5–45%) and quartz (36–62%), with significant amounts of feldspar minerals (orthoclase and albite) and muscovite. Okhoro samples, however, are overwhelmingly quartz-dominated (88.6–98.04%) with only minor kaolinite (0.98–9.42%) and no detectable feldspars, signifying a highly mature, intensely weathered sediment. These mineralogical differences indicate that Igo represents a submature kaolinite-quartz-feldspathic clay, while Okhoro represents a supermature quartzose deposit. Comparisons with industrial specifications show that both clay types meet some requirements for refractory bricks, hough beneficiation is needed to adjust fluxing oxide levels. Igo clays, due to their higher kaolinite content and natural feldspar fluxes, exhibit stronger potential for ceramic applications, including tiles, earthenware, and fillers for paint or rubber after processing. Okhoro clays, because of their extreme quartz dominance , are more suitable as construction fillers, low-grade refractory blends, or materials for brick manufacturing. Overall, the Igo clay deposit displays broader and more economically valuable industrial potential than the Okhoro deposit, which is limited by its mineralogical maturity.