Deinham's Danube cache holds about 1 tonne of Iron Age bars
Gravel work at Deinham, on the Danube in Upper Austria, raised at least 500 double-pointed iron bars weighing about 1 tonne. Radiocarbon places the bars in the La Tène centuries, and that mass is enough iron for roughly 500 swords at 1.5 to 2 kilograms each. The bars lay in a silted branch of the river, in a load most likely lost from a boat.
Science··Midday
At least 500 bars came out of the gravel
Gravel extraction at Deinham, on the right bank of the Danube in Upper Austria, brought up at least 500 double-pointed iron bars. Nature's 23 September account puts that cache at about 1 tonne and treats the load as roughly 500 swords. Antiquity's 21 September news calls the same Deinham bars Europe's largest known assemblage of prehistoric iron bars and puts the combined weight above 1 tonne. The pieces are semi-finished bars, not blades pulled finished from the gravel. Both accounts locate the metal on the Danube at Deinham, and both put the scale at a tonne-class cargo of hundreds of bars rather than a handful of tools.[1], [2]
Radiocarbon sits in the La Tène centuries
Antiquity's news says Peter Trebsche of the University of Innsbruck and Marion Berranger radiocarbon-dated the Deinham bars to the La Tène period, and it places the production scale they describe in the third and second centuries BCE. Nature's 23 September summary places the shipment about 2200 years ago and says the metal moved along the river. Those two clocks meet in the same Late Iron Age window: 2200 years before 2026 lands in the third century BCE, inside the span Antiquity names. The radiocarbon sample dates the bars. They are a new morphological variant in the Antiquity news, not the shorter Hallstatt pieces used as the comparison from Durrenentzen in France.[1], [2]
The sword figure is a comparison, and the loss is a boat
Antiquity's news says the bars were likely lost from a boat in a silted branch of the Danube. Trebsche's comparison, quoted there, is that about 1 tonne of iron is enough for roughly 500 swords at 1.5 to 2 kilograms each, even after manufacturing loss, or for a large group of warriors. Nature's summary matches the 1 tonne and the roughly 500 swords, and it says the metal was shipped along the river about 2200 years ago. Nature does not add a separate inventory of finished weapons from the gravel. The published object in both accounts is the bar cargo. The sword number is what that cargo could forge, not a count of blades recovered at Deinham.[1], [2]
