Abstract: Potassium chloride of at least technical grade is recovered from sylvinite or sylvinite-like starting materials (sylvite) by leaching with hot mother liquor recycled from a crystallizing stage, the residue consisting substantially of sodium chloride is separated and the solution is cooled to crystallize the potassium chloride. In order to avoid losses to potassium chloride and to reduce problems relating to equipment materials in separating water-insoluble impurities the finely ground starting materials are treated at ambient temperatures with a solution which is saturated with sodium chloride and potassium chloride, and water-soluble impurities are entrained with the solution. The solution is then separated from the water-insoluble impurities and is recycled at least in part to produce the pulp.