The pyrotechnic and thermal properties of a range of binary magnesium-strontium nitrate compositions containing from 10% to 90% by mass of magnesium have been determined. The burning rate and light output were measured after consolidating the compositions into cardboard tubes. The exothermicity, temperature of ignition and time to ignition of the compositions were also determined and the products of combustion were characterized. The compositions were found to burn reliably over the range 20% to 70% magnesium. The composition containing 70% magnesium was found to have the maximum burning rate and light output, while the maximum exothermicity was observed at 40% magnesium. The temperature and times of ignition decreased as the magnesium content was increased to 40% and thereafter did not change significantly.