Silica (Dune) Sand from the Red Deer Area, Alberta

Dune sands from the Red Deer area in central Alberta contain particle sizes predominating in the 70 to 100 mesh (0.210 to 0.149 mm) range. The chemical composition varies between 73 to 87 per cent SiO2; 6 to 9 per cent Al2O3, P205, and TiO2; 1.2 to 1.7 per cent Fe203; 0.7 to 6.8 per cent CaO; 0.3 to 1.8 per cent MgO; and 1.0 to 7.6 per cent loss on ignition. Mineralogically the sands contain more than 85 percent quartz, less than 10 per cent feldspar, and less than 10 per cent other minerals (goethite, garnet, hornblende, and magnetite). The grains are mainly subrounded and commonly stained.

Beneficiation tests on the sands included screening, washing, heavy liquid separation, magnetic separation, and acid treatment. Heavy liquid and magnetic separation procedures effectively reduce the iron content of the sands to a minimum of approximately 0.30 per cent in selected samples.