A search for archaeological artefacts made of meteoritic iron has turned up a Bronze Age arrowhead made from a meteorite that crashed to Earth 3,500 years ago.
The arrowhead was originally discovered in the late 1800s in Mörigen, Switzerland. It sat in Bern Historical Museum for years, assumed to be just like any other arrowhead. But the artefact, produced by Bronze Age hunters around 900–800 BCE, has origins that are out of this world.
Analysis of the arrowhead is published in the Journal of Archaeological Science.
“On the outside it looks like a typical arrowhead coated in rust,” lead author Beda Hofmann, head and curator of mineralogy and meteorites at the Natural History Museum of Bern, says in an article on Live Science.
Scientists used several methods to study the object.
X-ray tomography was used to produce computer images of the arrowhead. Gamma spectrometry showed aluminium-26 isotopes that do not naturally occur on Earth as well as traces of iron and nickel alloy consistent with meteorites.
The arrowhead shows grind marks from when it was shaped into an arrowhead, and tar remains likely used to attach the point to an arrow shaft.
Researchers were surprised by the site from which the meteorite was likely retrieved to make the arrowhead.
It was originally assumed to be linked to the 170,000-year-old Twannberg meteorite site, less than 8 kilometres from Mörigen. However, concentrations of nickel and germanium match those found in the 3,500-year-old Kaalijarv meteorite site in Estonia, more than 2,250 km away.
The 2.9-gram object would have come from the remains of a 1,800 kg meteorite according to the authors.
“It’s been well documented that trade was well established over large distances during the Bronze Age,” Hofmann notes. “These early people likely knew that when the impact happened there in 1500 BCE, the material was precious and had value to it.”
Only 55 meteoritic arrowheads are known from 22 sites across Eurasia and Africa.
Of these, 19 can be found in the tomb of Ancient Egyptian boy pharaoh Tutankhamun who died in 1323 BCE. “King Tut’s” burial chamber also houses a unique 34-centimetre dagger forged from a meteorite that fell to Earth more than 3,300 years ago.
Humans developed the technology to smelt iron (melting point 1,500°C) when the Iron Age began about 1200 BCE.