Fig. 1 shows exemplar optical image

Fig. 1 shows exemplar optical images of cold sintered xBF12-(1-x)LMO composites in which the black colour arises due to the presence of the ferrimagnetic BF12 phase. XRD traces of cold sintered xBF12-(1-x)LMO are shown in Fig. 2. Each trace depicts two structures, BF12 and LMO, with no evidence of parasitic phases arising from interfacial reactions. The relative intensities of the BF12 peaks increase with x. SEM images of xBF12-(1-x)LMO composites as a function of x are shown in Fig. 3. The microstructure exhibits a two phase mix (as confirmed by EDX spectra, Fig. 4) with smaller BF12 surrounding larger LMO grains and little porosity. Consistent with the XRD results, no secondary phases were observed in the SEM images.