In the absolute method for determining thermal conductivityK, the difference in temperature between two points along a rod is measured under conditions of steady‐state flow of heat. The thermal diffusivity &kgr; may also be determined from measurements of the time required for this temperature difference to decrease to half the steady‐state value when the source of heat is removed. FromKand &kgr; data, the specific heat may be calculated, using the general relationshipC=K/&kgr;&rgr;, where &rgr; is the density. The technique permits determination ofK, &kgr;, andCwith a single, small specimen having a wide range ofKand &kgr;. By observing simple experimental precautions, agreement to within 5%–10% has been obtained, for neodymium‐doped yttrium oxide, betweenCvalues calculated fromKand &kgr; data and those derived from calorimetric data.