The static dielectric constant epsilon of buckminsterfullerene (C-60) particles is determined in cis-decalin, toluene, and 1,2-dichlorobenzene using continuum models for spherical and spherical shell inclusions. The value for epsilon for isolated C-60 in cis-decalin and toluene agrees well with molecular beam measurements using a spherical shell model, but the epsilon estimate in the highly polar solvent 1,2-dichlorobenzene deviated from these other measurements. Complications of measurements in highly polar solvents are summarized. We conclude that virial measurements have a great potential for determining the effective properties of nanoparticles from the properties of nanofilled materials over a range of dilute filler concentrations.