Additives can be added to fertilizers to impart desirable characteristics. For example, a class of additives have been disclosed to stabilize the explosive potential of AN fertilizers are desirable, however, such additives can react with the AN fertilizer during its manufacture or during its storage. This is particularly the case where the additives contain carbonates, oxides, hydroxides, contain water of hydration or water locked within the structure (e.g. within an interlayer substructure). This reaction can be avoided if the additive has a passivation layer substantially covering the surface of the additive. The passivation layer, being substantially non-reactive and substantially insoluble, protects the additive so that the additive keeps its desired properties and the fertilizer keeps its quality. In other aspects, methods of making the fertilizer are provided.
