A sunken ship cargo of 500 bipyramidal bars? Implications for La Tène period iron production and trade along the Danube

Water is not kind to iron, as demonstrated by the ‘rusty treasure’ uncovered at Deinham in Upper Austria, now revealed as the largest assemblage of bipyramidal iron bars yet found in Europe. While similar bars are generally attributed to the Early Iron Age (eighth–fifth centuries BC), the authors here argue that the Deinham bars are a new variant, radiocarbon dated to the Late Iron Age (fourth–first centuries BC). Discovered in a silted-up branch of the Danube River, the bars were likely lost in a shipwreck, permitting speculation as to the purpose and exchange value of this weighty cargo.