METHOD FOR TREATING PHOSPHATE ROCK

A method for treating calcium sulphate containing rare earths comprising the steps of sulphuric-acid leaching of dehydrated cured calcium sulphate containing said rare earths, thus obtaining a suspension formed from a solid phase containing said dehydrated calcium sulphate and a liquid phase containing said rare earths in solution, and a separation of said solid phase formed from said dehydrated calcium sulphate and said liquid phase in the form of a solution containing said rare earths and sulphuric acid, the leaching solution thus obtained and the calcium sulphate.