A team of researchers have confirmed that a Bronze Age arrowhead found 150 years ago in Switzerland was made of iron from a meteorite – but not the meteorite they expected.
The discovery was made during a recent study of archaeological artefacts from the area near Lake Biel, with the aim of identifying objects made of meteoric iron from the 170,000-year-old Twannberg meteorite, which fell nearby. However, the analysis revealed just one meteoric iron object, and to the team’s surprise, the metal did not come from the Twannberg meteorite. The 39mm-long iron arrowhead was found in 1873/74 at a Late Bronze Age site in Mörigen, dated to 900-800 BC. During the recent research, the team applied various non-destructive methods to study the metal’s composition, including light microscopy, X-ray tomography, and gamma spectrometry, among others. This revealed that the object was definitely made of meteoric iron, but the content of nickel (8.3%) was twice as high as that of the Twannberg meteorite; the metal must have come from another source.
Based on the concentrations of nickel and germanium, it is believed that the most likely contender is the Kaalijarv meteorite, which fell in Estonia, probably around 1500 BC. If this is the case, it would mean that the fragment of iron had been transported over 1,600km across Bronze Age Europe – perhaps along the same trade routes as amber coming from the Baltic region – and demonstrates that iron meteorites were being used and traded in central Europe by 800 BC, and possibly earlier.
Until the start of the Iron Age, when people worked out how to extract iron from ore, meteorites were the only source of the metal. This made it a very rare resource – only 55 pre-Iron Age meteoric iron objects are known from all of Eurasia and northern Africa
(19 of them from Tutankhamun’s tomb). It is therefore unlikely that the Mörigen arrowhead was used for everyday hunting; perhaps it had some kind of prestige or symbolic function?
The research has been published in the Journal of Archaeological Science (https://doi.org/10.1016/j.jas.2023.105827), and the object will be on display in
the exhibition, And then came bronze! at Bern Historical Museum next year. As for the original research question, the fact that no artefacts made from the Twannberg meteorite were identified suggests that perhaps its existence was not known at the time.
Text: Amy Brunskill