  Ag/Fe/Ag and Cr/Fe/Cr trilayers with a single $25 nm$ thick ferromagnetic
layer exhibit giant magnetoresistance (GMR) type behavior. The resistance
decreases for parallel and transversal magnetic field alignements with a
Langevin-type magnetic field dependence up to B=12 T. The phenomenon is
explained by a granular interface structure. Results on Fe/Ag multilayers are
also interpreted in terms of a granular interface magnetoresistance.
