The late Eocene Medicine Pole Hills sandstone in SW North Dakota has been studied extensively because of its diverse mammalian fossil fauna and to assess its correlation to the Chalky Buttes Member of the Chadron Formation. This study verifies the internal consistency of heavy mineral analysis on the Medicine Pole Hills by comparing analyses from different stratigraphic positions and different grain sizes. This study contributed analyzed data of four different stratigraphic positions and two different grain sizes within the Medicine Pole Hills sandstone for these larger investigations. Older studies of the Chalky Buttes Member in the region used very fine grains while more recent studies, including the Medicine Pole Hills sandstone, have used medium grains to perform heavy mineral analyses. This study concludes that these data sets are compatible for use in comparisons because of the minimal effect of grain size on the heavy mineral abundances. The idea of size shift of the major constituent heavy minerals was investigated using absolute abundances by mass of these samples, but it was determined that more size intervals need to be analyzed to clearly identify trends in size shift. Cluster analysis of data from this study combined with other heavy mineral analyses on the Medicine Pole Hills sandstone and Chalky Butte Member reinforces that neither differences in stratigraphic position nor differences in grain size are sufficient to separate samples from within the same sandstone from one another or cause the Medicine Pole Hills samples to correlate with Chalky Buttes Member sandstones.