Abstract: A process for the production of a mixed crystalline non-caking granular mineral fertilizer based on ammonium salts such as ammonium sulphate, ammonium nitrate or ammonium phosphate, as well as mixtures thereof, optionally with further additives, comprising forming a melt or solution susceptible of granulation of the ammonium salts, adding dicyandiamide in an amount to result in a total content of 0.1 to 10% by weight, to the melt or solution susceptible of granulation of the ammonium salt prior to its granulation and then effecting granulation of the ammonium salts.