Cordierite is a naturally occurring magnesium aluminosilicate and in the MgO–Al2O3 – SiO2 ternary system, the stoichiometric point of cordierite corresponds to the composition of 2MgO·2Al2O3·5SiO2. Cordierite is characterized by a complex polymorphism dominated by two thermodynamically stable α- and β-cordierite phases. In this work two illite type clays (A and B) from local deposits were used to obtain cordierite ceramic materials. Mixtures corresponding to stoichiometric cordierite composition were obtained by mixing these clays with MgCO3, Al(OH)3 and ground quartz sand. Samples from compositions containing A and B were tested for their thermal properties using dilatometry for CTE measurements, laser “flash” analysis for thermal conduction, diffusion and heat capacity and water quenching/acoustic analysis for determination of thermal shock behavior. The results of thermal shock evaluation over cycled water quenching/drying show that sample A passed all 10 test cycles without reaching the elastic modulus reduction threshold of more than 30%, while sample B reached this limit twice – after cycles 5 and 10. It can be concluded that the materials made of composition A are more resistant to thermal shock than the composition B. A phenomenon of “self-healing” effect (a recovery of previously “lost” elastic modulus) was observed for both samples over the course of cyclic thermal shock treatment.