TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Process: The process further comprises: cooling the silicon- and germanium-bearing metal phase preferably to 450-600 degrees C, before the purification step to convert at least a part of the silicon and of the germanium present as a solute in the silicon- and germanium-bearing metal phase to the solid state; subjecting the separated zinc-chloride to molten salt electrolysis to recover zinc and chlorine; recycling the zinc to the contacting step; recycling the chlorine to a silicon and/or processing of germanium chlorination for the production of silicon tetrachloride and/or germanium tetrachloride; solidifying the purified liquid germanium-bearing silicon alloy using the ribbon growth method or directional solidification (preferred); granulating the purified liquid germanium-bearing silicon alloy; feeding the granules to a melting furnace; and applying a single solidification step, using the ribbon growth method or directional solidification in particular. The contacting and the separating steps are performed simultaneously at a temperature above the boiling point of zinc-chloride to evaporate the zinc chloride. The silicon and germanium present in the solid state is separated to form the silicon- and germanium-bearing metal phase that is further processed in the purification step. The contacting step is performed by injecting silicon tetrachloride and germanium tetrachloride into a bath comprising molten zinc, at a flow rate greater than 10 and up to 50 kg/minute per m2 of bath surface. The purification step is performed at a temperature above the melting point of the germanium-bearing silicon alloy to form purified liquid germanium-bearing silicon alloy. The purification step is performed at reduced pressure or under vacuum. The zinc that is vaporized in the purification step, is condensed and recycled to the contacting step. The un-reacted fractions of silicon tetrachloride and germanium tetrachloride are recycled to the contacting step. The solid material is wafered and further processed to solar cells. Preferred Components: The total amounts of silicon tetrachloride and germanium tetrachloride are chosen so as to obtain a germanium-bearing silicon alloy with 1-5 wt.% of germanium. The silicon- and germanium-bearing metal phase contains at least part of the silicon in the solid state. EXAMPLE - Metallic zinc (8500 g) was heated to 850 degrees C in a graphite reactor. Then germanium chloride (50 g) was injected with a flow rate of approximately 250 g/h. The zinc chloride, which evaporated during the reaction, is condensed, collected in a separate vessel. Any un-reacted germanium tetrachloride was collected in a wet scrubber connected to the zinc tetrachloride vessel. The formed germanium completely dissolved in the zinc. Then, silicon tetrachloride (5500 g) was injected in the same way with a flow rate of approximately 250 g/h. This corresponds to 0.66 kg/minute per m2 of bath surface. The evaporating zinc tetrachloride was again condensed and collected. Any un-reacted silicon tetrachloride was collected in a wet scrubber connected to the zinc tetrachloride vessel. A germanium-bearing silicon alloy, saturated in silicon at the prevalent reactor temperature, was obtained. The total silicon content of the mixture was 16.2%.