In former studies on archaeological cooking pots or archaeological pyrotechnical ceramics their thermal conductivity was discussed only in relation with other parameters but, it was never actually determined. In the present study a modified Lees' disk setup was used in order to determine the thermal conductivity of a series of experimental ceramic disks. As for the manufacture of these disks typical ceramic fabrics were simulated, which can be observed in archaeological cooking pots. In order to assess the effect of production parameters on the thermal conductivity, two different clays, one non-calcareous and one calcareous, were tempered with different amounts of granite or phyllite and were fired at three different temperatures: 550 degrees C, 850 degrees C and 1050 degrees C. The most important parameters emerged as the degree of vitrification and porosity of the ceramic matrix. (C) 2008 Elsevier B.V. All rights reserved.