Most of the well-stratified Early Bronze Age metal objects from Poliochni, with the exclusion of one hoard find, were analyzed for their chemical and lead isotope compositions. The results show that a major change occurred in the metal used at Poliochni during periods contemporary with Troy I and Troy II. Unalloyed or arsenical copper with relatively high lead contents during the earliest two periods, <i>azzurro</i> and <i>verde</i>, is gradually replaced and supplemented by tin bronze which, during period <i>giallo</i>, i.e., by the end of Troy II, becomes the dominant metal type. Lead isotope abundance ratios in the earlier artifacts are consistent with a derivation of the metal from regional ore sources but the trace element abundance pattern is not. Concurrent with the appearance of tin bronzes is an increase in the diversity of ore deposits exploited; for about one-third of the artifacts from period <i>giallo</i> there is as yet no matching ore source in all Anatolia and the Eastern Mediterranean. It is argued that the tin bronzes have been imported as such but that the lead isotope signature does not provide any direct clues to the origin of the tin.