Characteristics and ceramic properties of clays from Mayoum deposit (West Cameroon)

Four clay samples from Mayouom deposit were studied to evaluate their potential uses in the ceramic industry. Characterization of crude clays involved chemical and mineralogical composition, plasticity and particle size distribution. Fired properties of clays were measured in terms of densification parameters viz linear firing shrinkage, bulk density, open porosity and water absorption. The samples denoted as MY38, MY41g and MY45g were found to be poor in sand and highly plastic, whereas MY45s is sandy and has low plasticity. The alkali and alkaline earth oxides compositions are low (< 0.9 %) while the colouring oxides (TiO2 + Fe2O3) are 0.4-6.1 %. In all the samples, kaolinite is the dominant mineral associated with quartz, illite, goethite, apatite, rutile or anatase. Test-discs from sand-poor samples show important linear firing shrinkage vitrifying above 1300 degrees C, whereas the shrinkage in MY45s was small, its ceramics also vitrified at high temperatures. These properties show that these clays can be successfully used as refractories. In addition, due to its white firing colour, MY45s can be very suitable for use in the production of porcelain and vitreous china.