Ancient silver artifacts, when exposed to environments that contain sulfides (H2S), become tarnished and a black film is formed on the surface. The current study deals with the role of copper content and oxygen in the formation of tarnishing in the silver alloys 0.925, 0.800 and 0.720. An ammonium sulfide solution was used as an accelerator of the tarnishing process for different immersion conditions. The analysis of the tarnishing layer in silver alloys was performed by Raman Spectroscopy, Scanning Electron Microscopy - Energy Dispersive X-ray spectroscopy (SEM-EDS) and X-Ray Fluorescence (XRF). The formation of the tarnishing layer was found to be influenced by copper and oxygen contents. The corrosion products under the conditions studied were found to be mainly acanthite and jalpaite.