Thermal analysis-mass spectrometry (TA-MS) has been used to study the reactions of Al Maghara coal and its low temperature ash (LTA) under combustion-related conditions. The TA-MS profile of the coal gives information on combustion performance (ignition, peak combustion and burnout temperatures) and on chemical changes to the volatile matter (H2O, SO2, CO2 and NO2), char and minerals. X-ray diffraction identified pyrite as the major mineral component in the coal. The major and only feature of the TA-MS profile of the LTA is SO2 evolution associated with decomposition of pyrite and iron sulphates. The high sulphur content of Al Maghara coal is a severe obstacle to its use in combustion. Cleaning of the coal to reduce the sulphur to an acceptable level is considered to be essential.