Packings of micron -sized spherical particles ? Insights from bulk density determination, X-ray microtomography and discrete element simulations

•Determination of packing fraction of copper, glass and zirconia particles.•Comparison of results from bulk density measurements, CT and DEM.•Experimentally determined packing fractions agree well with DEM results.•Confirmation of a simple relationship for dependence of packing fraction on size.•DEM proves that mean coordination number result is sensitive on the CT resolution.