The chapter discusses the variation of peak temperature with heating rate in differential thermal analysis (DTA). DTA is a widely used method in mineralogical laboratories to record thermal effects during sample heating, where deflections in the differential temperature curve represent changes in heat content. The peak temperature, which often differs from the known transition or decomposition temperature, is influenced by factors such as heating rate and technique. The work of Murray and White on the kinetics of clay mineral decomposition provides a theoretical framework for interpreting DTA patterns. They derived an equation that relates the peak temperature to the kinetic constants of the material and the heating rate. This equation was tested using kaolinite and halloysite samples, with results showing that the peak temperature varies with heating rate, as predicted by the equation. The study also found that the precision of DTA measurements is limited by the standard deviation of a single measurement, and the agreement between DTA and isothermal results confirms the validity of the theoretical model.The chapter discusses the variation of peak temperature with heating rate in differential thermal analysis (DTA). DTA is a widely used method in mineralogical laboratories to record thermal effects during sample heating, where deflections in the differential temperature curve represent changes in heat content. The peak temperature, which often differs from the known transition or decomposition temperature, is influenced by factors such as heating rate and technique. The work of Murray and White on the kinetics of clay mineral decomposition provides a theoretical framework for interpreting DTA patterns. They derived an equation that relates the peak temperature to the kinetic constants of the material and the heating rate. This equation was tested using kaolinite and halloysite samples, with results showing that the peak temperature varies with heating rate, as predicted by the equation. The study also found that the precision of DTA measurements is limited by the standard deviation of a single measurement, and the agreement between DTA and isothermal results confirms the validity of the theoretical model.