The solid solutions [Pb,Sr](NO3)(2) and [Pb,Ba](NO3)(2) show a multiplicity of Pb-207 NMR signals, arising from shifts of the Pb-207 resonances by less polarizable neighbors. The shifts have a unique anisotropic signature that allows tentative assignment of some of the signals. Monte Carlo simulation of the spectral intensities shows that the ions are slightly clustered in the crystal, which disagrees with:a conventional but specious analysis of the dependence of the unit cell volume on composition. The extent of the clustering is attributable to the differences between the van der Waals interaction energies of the ions.