A unique commercial lead weight from the western Black Sea region is examined in its metrological and historical context.
The style and combination of relief symbols on the object (Athenian owl and Kyzikene tuna) suggest a quarter mina in a market weight-system used equivalently at Athens and Kyzikos by the last quarter of the 5th cent. B.C.
The weight reflects a long-term process of broad commercial integration of the Aegean and Black Seas in Classical times. Such a process was most likely caused by the economic motivations of individual city-states, not the direct Athenian imperialism expressed in the Standards Decree (IG I3 1453).
