An international group of researchers in Switzerland has discovered that a late-Bronze Age arrowhead was originally built out of meteoritic iron, according to a study published in August in the Journal of Archaeological Science.
Weighing 2.9 grams and measuring about one and a half inches long and less than an inch wide, the rust-covered arrowhead was initially excavated in the late 19th century from a prehistoric habitation near Mörigen on Switzerland’s Lake Biel, according to the study coordinated by the Natural History Museum of Bern. This site is less than five miles southwest of a known field in Bernese Jura, bestrewn with over 2,000 fragments from the Twannberg meteorite, the largest of the eight meteorites that have been found in Switzerland, according to the Natural History Museum of Bern. Led by Dr. Beda Hofmann, the research team examined the arrowhead with several non-destructive analysis techniques, including X-ray fluorescence, a process that analyzes an object’s chemical composition, and high-sensitivity gamma spectrometry, a method that detects radioactive materials.
Through these studies, the researchers found that the flat arrowhead revealed a deformed laminated texture resembling the distinct Widmanstätten pattern — layered crystalline markings characteristic of iron meteorites. These analyses also showed that the arrowhead was composed of aluminum-26 isotopes, a “cosmogenic” chemical element, as well as traces of an iron and nickel compound that is consistent with meteoritic content, according to the researchers’ findings. However, the iron arrowhead’s structure did not match the scattered fragments of the Twannberg meteorite. Instead, researchers believe that the arrowhead came from a different space rock that fell over 3,500 years ago and left a group of craters in present-day Estonia. They suspect that the meteoritic iron was subsequently traded after it was unearthed, and that additional artifacts originating from the same meteorite “may be present in archaeological collections,” according to the study.
“It is almost impossible to ‘see’ that iron is meteoritic,” Hofmann, who heads the Natural History Museum of Bern’s Earth Sciences Department, told Hyperallergic in an email. “Mostly, these are not too attractive-looking rusty objects.”
Hofmann added that he thinks more information can be gathered if archaeological collections in Europe and beyond were “more or less systematically searched for early meteoritic iron,” especially those containing iron artifacts dating back to the Bronze Age.
“Once more meteoritic objects are identified, additional analyses could be performed to test the source,” Hofmann said.
Before 1200 BCE, iron was a rare material and mostly sourced from meteorites that fell to Earth, according to research published in the Journal of Archaeological Science in 2017.
“Archaeological objects made of meteoritic iron are extremely rare,” according to a news release published by the Natural History Museum of Bern. While meteoritic iron is known to have been used in 55 objects found in 22 different sites across Europe, Asia, and Africa, these artifacts are extremely uncommon in central and western Europe, having only been found twice, both times in Poland: an axe in Wietrzno-Bobrka and bracelets in Częstochowa-Raków, according to the study.
The iron arrowhead will be on display at the Bern History Museum as part of a special Bronze Age exhibition opening in February 2024 and running until April 2025.