Abstract: A process for the production of phosphorus from low-grade phosphate rock containing at least 5% by weight of each of iron and aluminum (calculated as their oxides) by heating a mixture of the rock, calcium oxide and a carbonaceous reductant in a reaction chamber at a temperature of at least 1400.degree. C to produce molten reaction products containing ferrophosphorus and a calcium aluminate slag which is liquid at the reaction temperature, and gaseous reaction products containing elemental phosphorus. The gaseous reaction products are withdrawn from the reaction chamber and elemental phosphorus is recovered therefrom. The ferrophosphorus is separated from the liquid calcium aluminate slag and subjected to an oxidizing treatment in the presence of a calcium-containing material to produce metallic iron and calcium phosphate. Calcium phosphate this produced is recycled to the reaction chamber.