Alberto: Unless we are suffering from some international misunderstanding my definition of muriate of potash is KCl.. See below: "Muriate of Potash: It's odd how this old-fashioned name remains in use! Muriate comes from Muria, the Latin for brine. Muriate of potash is potassium chloride containing between 50 and 60 per cent potash. It was deposited eons ago by ancient seas and should be considered a natural product, blessed by organocultists, but it is not. Its chlorine content passes off rapidly when applied to soil. As explained under soil organisms, however, muriate of potash is harmful to certain beneficial bacteria. Some authorities think sulfate of potash makes a better potash fertilizer." Arnold