A method of treating a spent potliner after use in an aluminum smelting process, the method comprising crushing and classifying the spent potliner, placing the classified and crushed spent potliner in a furnace at a temperature greater than 450.degree. C., heating the spent potliner to a temperature greater than 450.degree. C., mixing the heated spent potliner with water to produce reaction gases and residue, burning the reaction gases, mixing the residue with water in a well ventilated area for a period of weeks to cure the residue. The method also embraces blending the cured residue with other chemicals and minerals to provide specific mineral products.