131 Roman sesterces were analyzed from the period of Augustus (27-14 B.C.) to Gordian III (238-244 AD) by means of atomic absorption spectroscopy. It was found that the composition of these coins changes continuously. The amount of zinc decreases during these 250 years from 27% to 0%. The reduction of zinc is compensated by an increase of tin and lead. The use of copper ores from different mining areas is marked by an obvious variation of antimony during the early and late periods. -- AATA