  Persistent currents and Drude weights are investigated for the tight-binding
approximation to one-dimensional rings threaded by a magnetic flux and with
potential given by some almost-periodic substitution sequences with different
degrees of randomness, and for various potential strengths. The Drude weight D
distinguishes correctly conductors and insulators, in accordance with the
results shown by the currents. In the case of insulators the decay of D(N) for
large ring lengths N provides an estimate for the localization length of the
system. It is shown that the more random the sequence does not imply the
smaller conducting properties. This discrepancy between the hierarchy of
disorder of the sequences and the capacity of conduction of the system is
explained by the gaps in the energy spectra.
