RESEARCH Physico-chemical and geotechnical characterization of Bargou clays (Northwestern Tunisia): application on traditional ceramics A. Bennour 1,2 & S. Mahmoudi 3 & E. Srasra 4 Received: 8 April 2017 /Revised: 13 July 2017 /Accepted: 8 September 2017 # Australian Ceramic Society 2017 Abstract 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 character- ization 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 consid- ered as a non-refractory material. The X-ray diffraction min- eralogical analysis on whole rock and clay fractions reveals the presence of phyllitic minerals (illite, kaolinite, and inter- stratified illite/smectite). Associated minerals are mainly rep- resented by dolomite, calcite, quartz and feldspar, and occa- sionally gypsum. The chemical analysis of major elements reveals a moderate level in Al 2 O 3 (10–18%) and SiO 2 (36– 64%) with a SiO 2 :Al 2 O 3 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 resis- tance 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. Keywords Bargou clays . Lower aptian clays . Traditional ceramic . Ceramic properties . Thermal behavior Introduction The inventory of mineral substances of Tunisia carried out by the National Office of Mines enabled us to bring to light a number of indices of materials which can have industrial uses. Accordingly, various prospection studies have been interested in these inventoried fields (e.g., [2–4, 6, 14, 15, 18–21]). The Drija clays are part of this group and they have been subjected to a systematic study in order to elucidate their min- eralogical and chemical characteristics and to identify their industrial use, namely, setting up a pottery factory. The study zone is located in the center of Bargou Mountain and within the topographical map, at 1/50000 from Bargou, at the coordinates UTMC: X = 564810; Y = 3991486 (Fig. 1). The entry to the field is through the main road linking the capital, Tunis, to the village of Bargou then by the paved road which leads to the village of Drija at a distance of roughly 5 km. The geological study shows that the studied zone is com- posed of marley-calcerous alternations with overlying gray clays. The middle part of this lithological section is character- ized by the presence of gray and green silteous clays interca- lated by small sandstone levels. At the summit, the lithological section ends with marley-calcerous alternations representing the carbonate series of the transition to the Upper Aptian geo- logical stage. * A. Bennour bennour_ali@hotmail.com 1 Department of Geology, Faculty of Sciences of Bizerte, 7021 Zarzouna, Tunisia 2 Mineralogical Laboratory, National Office of Mines, 3023 Charguia I, Tunisia 3 Department of Earth Sciences, Faculty of Sciences of Gabes, 6072 Zrig, Tunisia 4 Physical Chemistry Laboratory of Mineral Materials and its Applications National Centre of Research in Materials Sciences BP95, 2050 Hammam Lif, Tunisia J Aust Ceram Soc DOI 10.1007/s41779-017-0136-5