GEOTECHNICAL CHARACTERISTICS OF SOME CLAYS FROM SOUTH-WESTERN NIGERIA - IMPLICATIONS FOR INDUSTRIAL UTILIZATION

Clays in adequate quantity and of quality for industrial use occur in the Ifon area of Ondo State, Nigeria, in the form of alluvial deposits at Sobe, as sedimentary deposits at Ifon and Arimogija and as residual clays at Omialafara. The alluvial clays from Sobe and the sedimentary clays from Ifon are highly plastic while the sedimentary clays from Arimogija are moderately plastic and the Omialafara residual clays only slightly plastic. The clays in general are kaolinitic in composition with minor amounts of illite. The unconfined compressive strength characteristics of fired pellets of these various clays indicate that the reddish to greyish-brown alluvial clays at Sobe tend to have higher strength values than the dark gey clays of Arimogija. Porosity, firing shrinkage, clay mineralogy and colour after firing all indicate that the clays are very suitable for the manufacture of ceramic wares.