  The icosahedral (i-) AlPdRe is the most resistive quasicrystalline alloy
discovered so far. Resistivities ($\rho$) of $1\Omega cm$ at 4K and correlated
resistance ratios ($RRR = \rho_{4K}/\rho_{300K}$) of more than 200 are observed
in polycrystalline samples. These values are two orders of magnitude larger
than for the isomorphous i-AlPdMn phase. We discuss here the controversial
microscopic origin of the i-AlPdRe alloy electrical specificity. It has been
proposed that the high resistivity values are due to extrinsic parameters, such
as secondary phases or oxygen contamination. From comprehensive measurements
and data from the literature including electronic transport correlated with
micro structural and micro chemical analysis, we show that on the contrary
there is mounting evidence in support of an origin intrinsic to the i-phase.
Similarly to the other quasicrystalline alloys, the electrical resistivity of
the i-AlPdRe samples depends critically on minute changes in the structural
quality and chemical composition. The low resistivity in i-AlPdRe single-grains
compared to polycrystaline samples can be explained by difference in chemical
composition, heterogeneity and thermal treatment.
