The invention relates to a method for providing an inorganic coating to ammonium nitrate (AN) based particles, in particular to ammonium nitrate-based particles for use as a fertilizer, as well as to an inorganic coating for ammonium nitrate-based particles per se. The method comprises the steps of: a) applying a liquid concentrated mineral acid with a water content of less than 50 weight %, to the particles, in order to at least solubilize ammonium nitrate at the outer surface of the particles such that an acidifled particle grasping layer is obtained, and b) applying a solid mineral alkaline in powder form to the particles of step a) in order to react with the grasping layer of the particles to coat the acidified particle surface; wherein the stoichiometric ratio of solid mineral alkaline in powder form to concentrated mineral acid is equal to or more than 5:1.