For a superlattice containing a fraction x 6% = 0.80 of 6% Sn nanocrystals, examining the dipoles induced by excitation at the peak, we find that the 1% Sn nanocrystals are effectively acting as dielectric spacers that have minimal polarization, so 6% Sn nanocrystals near 1% Sn nanocrystals have significantly reduced dipoles because they do not get a mutual polarization boost (Fig. ). These effects weaken the overall response, reducing the extinction intensity. The field is also highly concentrated along the paths formed by 6% Sn nanocrystals, resulting in a heterogeneous distribution of field strengths and dipole orientations (Fig. ). In a superlattice with only a fraction x 6% = 0.20 of 6% Sn nanocrystals, conversely, the 1% Sn nanocrystals' polarization is enhanced by coupling to neighboring 1% Sn and 6% Sn nanocrystals alike, strengthening and better aligning their dipoles with the applied field (Fig. ). As a result, the low frequency extinction peak intensity falls off more gradually than expected from linear mixing as x 6% increases, and the local field enhancement is more evenly distributed (Fig. ). The spectral redistribution of extinction and spatial redistribution of electric field intensity hint at a rich variety of effective metamaterial properties and near-field phenomena that could be realized in mixed nanocrystal superlattices. MPM's ability to rapidly screen a large compositional parameter space will be enabling in the exploration of these possibilities.