Number of lithium-based oxide ceramics in Li–Al–Si–O system were synthesized by solid-state reaction route using Li₂CO₃, Al₂O₃, and SiO₂. The progress of the reaction was monitored using thermogravimetry. A modelfree approach was employed to fit the temperature versus mass loss data. Heat capacities were measured as a function of temperature using differential scanning calorimetry. Variation of lithium/silicon ratio resulted in change in heat capacity and average crystallite size in each compound.