PURPOSE: To recover F and rare earth elements, by a method wherein bastnaesite ore is roasted in the presence of moisture to gasify CO2 and F as hydride from fluorinated carbonate and, while the formed gaseous products are scrubbed with an aqueous alkali medium, a caustic alkali liquid is added to the roasted ore to extract the same with a mineral acid under heating.

CONSTITUTION: When bastnaesite ore is heated to 400°C or more in the presence of moisture, CO2 and F are gasified as a hydride from fluorinated carbonate by hydrothermal reaction. When said gas components are surubbed with an aqueous KOH or NaOH solution, F is fixed as CaF2 and recovered as a water insoluble precipitate. On the other hand, a conc. caustic alkali aqueous solution is added to the roasted ore to be heated to 120°C or more and said roasted ore is subsequently extracted with warm water to elute phosphorus. In addition, when the residue is extracted with a mineral acid, especially, conc. hydrochloric acid, 90% or more of rare earth elements are recovered as rare earth metal chlorides solution.