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New multinary amorphous materials, based on gold, that can be produced in bulk form due to their high glass-forming tendency, were discovered recently. However little is known about their corrosion properties.In the present study, the characterization of Au 49 Cu 26.9 Ag 5.5 Pd 2.3 Si 16.3 amorphous ribbons produced by melt spinning is reported. Their corrosion properties were tested by incubating the samples in artificial sweat and by monitoring the changes in surface structure by SEM and XRD. Before incubation, the surface of the samples was amorphous and flat, characterized only by microfeatures due to the liquid contact with the wheel during quenching. After treatment with artificial sweat, the formation of nanosized crystallites of Au on the sample surface was observed.The surface chemical composition of both sides of the ribbon samples was investigated by XPS. Atomic concentration and chemical states of constituent elements before and after the incubation in artificial sweat were determined. The depth profiling of both sides of the samples was carried out by using Ar ion sputtering combined with cyclic XPS measurements. The segregation of Si on one side of the samples and the changes of chemical composition, caused by the treatment in artificial sweat, were revealed.