Cupriferous mineralisations of red beds type occur in a pelagic serie of paleocene age belonging to the Préalpes Medianes nappe in the Préalpes Romandes (Switzerland) and the Chablais (France). The copper-bearing minerals form concentrations sparcily disseminated in marls which can be observed in the same stratigraphic horizon for over 60 kilometers along the strike. Two distinct mineral assemblages were found and studied: 1. native copper and cuprite, 2. bornite, chalcocite sensu lato, covellite and chalcopyrite. In the bornite, very small inclusions of an undetermined mineral contain the elements Fe, As, S and Se (determination by microprobe analysis). The copper-bearing mineralisations examined appear to be of no economic significance.