Abstract: Elemental silicon of utility as a corrosion resistant coating, as an absorber in a solar thermal conversion system, etc. is provided by nonaqueous electrolytic deposition thereof on a cathode body through electrolytic reduction of a silicon halide or haloid silane compound as a solute in a liquid aprotic dipolar organic solvent for the compound by passing therethrough an electrolyzing current, generally at near ambient temperature and near atmospheric pressure yet under cover of an inert gas, and desirably by pulse electrolysis. The electroplating composition consists essentially of a nonaqueous solvent solution of the anhydrous liquid aprotic dipolar organic solvent, for example propylene carbonate, dimethylformamide, etc., containing the silicon solute, such as illustrated by silicon tetrachloride and trichlorosilane, in an amount providing, or providing by inclusion therewith of a dissociable electrolyte (e.g.