An experimental comparison has been made between the properties of the surfaces of an Al@sub70@Pd@sub 21@Mn@sub 9@ quasicrystal and its Al@sub 48@Pd@sub 42@Mn@sub 10@ approximant. This investigation has attempted to identify connections between the quasicrystalline structure and bulk properties. The Al@sub70@Pd@sub 21@Mn@sub 9@ sample was a single grain icosahedral quasicrystal cut to expose its five-fold symmetric (000001) surface. The approximant was polycrystalline @beta@-phase Al@sub70@Pd@sub 42@Mn@sub 10@, which has a CsCl-type cubic structure. Surfaces of both were prepared under ultra-high vacuum (UHV) conditions and then used for comparative measurements of their frictional properties and oxidation rates. The aluminum based quasicrystals and their approximants are oxidized by reaction with O@sub 2@ to form a thin film of aluminum oxide that ultimately passivates their surfaces. The oxidation process was studied using Auger Electron Spectroscopy to measure the oxide film thickness following controlled exposures to both O@sub 2@ and H@sub 2@O. The interesting difference between the two samples is that the rate of oxidation of the approximant is significantly higher than that of the quasicrystal in spite of the fact that the bulk Al concentration of the approximant is lower than that of the quasicrystal. Friction measurements were made under UHV conditions between pairs of quasicrystals and pairs of approximants whose surfaces were either clean or oxidized to varying degrees. The friction measurements were made between pairs of clean surfaces and between pairs of surfaces exposed to controlled oxidation. The friction between pairs of the approximant surfaces is roughly twice that measured between the quasicrystal surfaces under all conditions of surface oxidation. The results of this work do suggest that there is a direction connection between the quasicrystalline structure and low friction.