Abstract: A method can, in one general aspect, include steps for the recovery of potassium sulfate and mirabilite from glaserite. In another general aspect, a method includes dissolving glaserite in water at an elevated temperature to produce a saturated or nearly saturated solution, and cooling the solution to a temperature where potassium sulfate and mirabilite will crystallize from the solution as stable phases. In yet another general aspect, a method includes adding glaserite to a saturated solution of glaserite in water and mixing for enough time at a temperature where the glaserite will decompose into potassium sulfate and mirabilite as stable phases. In yet another general aspect, a method includes separating potassium sulfate from mirabilite using a froth floatation process.