The use of chemical treatment for Quarternary clay with high illite content It is shown the influence of chemical treatment by different NaOH concentration on illite clays (clay Laza deposit Quaternary period) and the effect of this on the structure and some properties of the obtained ceramic material. It was determined that for chemically treated clays are observed structural changes connected with separation of water molecules from layers. That have effect on sintering temperature of ceramic material. It is shown that ceramic material from teated clays forms at lower temperatures in range from 600 up to 700oC, reaching compresive strength of 20-32 MPa