Enthalpy increment measurements in the range of (520 to 1570) K were carried out utilizing drop calorimetry on zirconolite (CaZrTi2O7). The high-temperature dependence of the heat capacity of zirconolite has been determined from the simultaneous analysis of our enthalpy increment measurements and published low-temperature heat capacity data. (c) 2005 Elsevier Ltd. All rights reserved.