The Lower Aptian clays of the Drija formation (Jebel Bargou-Siliana, Tunisia) have been studied for their use in the ceramic industry. The physico-chemical characterization and advanced technological tests were carried out on two samples, Bargou 1 and Bargou 2 using many analytical methods. The samples indicate that these clays can be considered as a non-refractory material. The X-ray diffraction mineralogical analysis on whole rock and clay fractions reveals the presence of phyllitic minerals (illite, kaolinite, and interstratified illite/smectite). Associated minerals are mainly represented by dolomite, calcite, quartz and feldspar, and occasionally gypsum. The chemical analysis of major elements reveals a moderate level in Al2O3 (10–18%) and SiO2 (36–64%) with a SiO2:Al2O3 ratio that can reach level 3 and a low CaO content. The plasticity index of the samples, cut from the Drija formation, shows that they are low plastic clays (l2% < IP < 15%). The drying curves of various samples show that the clay materials have a quick drying behavior since they have a relatively low drying shrinkage. The tested briquettes, fired at different temperatures of 950, 1050, and 1100 °C, remain flat without deformations or defects; they are of red brick color. These briquettes show a high mechanical resistance to flexion and a good sound. The results obtained show that the Drija formation clays of Lower Aptian from the Bargou region can be directly used in the manufacture of tiles.
Journal of the Australian Ceramic Society – Springer Journals
Published: Oct 12, 2017