The application of image intensification techniques to the study of the spatial, temporal and spectral characteristics of the light emitted during the crystallisation of sodium chloride is described. The crystallisation is induced by adding concentrated hydrochloric acid to a saturated aqueous solution of sodium chloride. It is found that during an early stage of its growth a homogeneously nucleated crystal emits a burst of some 105 photons (measured in the range 390 to 570 nm). Assuming that this light emission accompanies an amorphous-to-crystalline transition in the growing 'crystal', simple thermodynamic arguments indicate that it occurs when the crystal diameter is of order 10-7 m. Comparisons of the crystalloluminescent spectrum with the photoluminescent spectra of the crystalline and dissolved salt suggest that the light emission occurs from crystalline sodium chloride. Temporal studies revealed some long-lived crystalloluminescent emission (lasting up to several seconds) that are consistent with local high levels of supersaturation. Overall, the results broadly support the conclusions reached in earlier photomultiplier-based work by Garten and Head (1963). Unlike photomultipliers, image intensifier allow the spatial behaviour of crystalloluminescence to be studied and provide a sensitive and accurate way of recording the spectra of these transient and low-level light emissions.