Thermochemical equilibrium calculations indicate the possibility of considerable fuel savings and CO2 emission avoidance in the three steps of the Pidgeon process: (a) calcination of dolomite; (b) production of ferrosilicon from quartz sand, coal, and iron oxide; (c) silicothermic reduction of calcined dolomite by ferrosilicon to magnesium. All three steps should benefit from application of concentrated solar energy as the source of high-temperature process heat, while the first two steps may be adapted to the coproduction of syngas. For the production of ferrosilicon, an experimental study was carried out by thermogravimetry as a model for a solar-driven process. The net reaction at 1823 K was shown to be represented by Fe2O3 + 4SiO(2) + 11C -> 2FeSi(s) + 10CO(g) + SiC(s) + SiO(g), confirmed by gas chromatographic analysis of the evolved CO and by XRD identification of the solid products FeSi and SiC. This product mixture agrees with that predicted for the thermochemical equilibrium, but differs from that reported in the literature for the electric arc process.