This work is devoted to the study of ammonium chloride (NH4Cl) crystallization from an aqueous solution in a stirred vessel. Initial supersaturation is created by the addition of potassium chloride (KCI) crystals into a nearly saturated NH4Cl solution. From continuous recording of both electrical conductivity and turbidity of the medium information can be derived about the crystallization rate and the granular state of the so formed NH4Cl crystals. These are ramified agglomerates of 5 mu m primary crystals. Their size is clearly correlated with the Kolmogorov microscale. Respective roles of primary and secondary nucleation, growth, agglomeration and fragmentation are discussed in the framework of a model.