Density is an essential comparative measure for all structural models of glasses. Molar volume and packing efficiency seek to normalise density for both the masses and volumes of ions before comparison to atomic-level order. In this presentation, packing fractions from five oxide glass systems were determined and compared to each other and to atomic-level structural models. Both short-range and intermediate-range order may be discerned in the resulting trends of packing fraction as a function of glass composition. Furthermore, in several specific glass systems, generalisations have been found in the packing trends that are independent of alkali type. In glasses with small modifier ions the packing is strongly influenced by the atomic structure of the glass forming network while in the case of larger modifiers random packaging of these large ions controls the overall packaging and is independent of modifier itself.
