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The Şahin-village clay deposit, situated in the vicinity of Kütahya, western Turkey, has a promising reserve suitable for tile production. In order to evaluate its potential use, 27 clay samples were collected and their mineralogical, chemical, firing and technological properties were evaluated. The reaction of samples with dilute HCl, dispersion in water and their swelling properties were determined. Mineral identification studies were conducted using X-ray powder diffraction (XRD), differential thermal analyses (DTA) and scanning electron microscopy (SEM) techniques. Analysis showed that clay minerals are illite, kaolinite and montmorillonite. Non-clay minerals are quartz, muscovite, microcline and goethite. The clay samples consisted mainly of SiO2 and Al2O3 corresponding to about 81–83% (average) because of the presence of clay minerals and quartz, accompanied by a significant amount of iron oxide. Mineralogical, chemical, thermal analysis and technological tests showed that the clays from Şahin village could be used for stoneware tiles, tile and brick-making.

The aim of this study was to identify interaction mechanisms among particles in the hydration of pozzolan cements. To this end, chemical, physical, mineralogical and electrokinetic analyses of samples were conducted. Furthermore, free surface energy components were defined by Van Oss, Chaudry and Good equations and the contact angle values of samples were determined by using the thin layer wicking method. The results show that the addition of water turns solid–air interfaces into solid–liquid interfaces (wetting), while attraction and repulsion take place depending on the electrical charges on particle surfaces. While total surface energy and components of particles seek to attain balance as a result of wetting, hydration and pozzolanic reactions occur.

This study was conducted to determine the interaction mechanisms among particles during the hydration of composite cements prepared with crystal and amorphous pozzolans. Chemical, physical, mineralogical and electrokinetic analyses of samples were conducted. Furthermore, free surface energy components defined with Van Oss, Chaudhury and Good equations and contact angle values of samples were determined by using the thin layer wicking method. The results demonstrate that particle charges, hydrophilic/hydrophobic properties of surfaces and surface energies could be effective in interactions of ordinary Portland cement and pozzolan suspensions.

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