Post-sintering below 950°C resulted in no considerable increase in the relative density, with compaction of the green pellets at 180°C providing the primary contribution to the final Li2Mg3TiO6 ceramics densification. There was only a minor change in the average grain size, with an almost constant size of ~30 nm for the samples sintered at 180°C–750°C, which was in agreement with the XRD analysis (Table 1).