Abstract: A method of producing a polyphosphate, orthophosphate, phosphonate or the like chemical treatment cake is disclosed. Conventional commercially available treatment material is obtained in powder form and mixed with water to initiate an exothermic reaction. The material is then poured into a mold and placed inside an insulated hermetic cabinet and allowed to quiescently cool in the passive environment of the cabinet. The cake is harder, more uniform and relatively free of inclusions compared to cakes formed by other methods.