Strange metal from beyond our planet found in ancient treasure cache: ScienceAlert
Amidst a wealth of glittering gold treasures from the Iberian Bronze Age, two corroded objects may be the most precious of all.
A blunt bracelet and a rusted, hollow hemisphere decorated with gold were, researchers found, forged not from metal found in the earth, but from iron from meteorites that fell from the sky.
The discovery was made under the direction of the now-retired head of the restoration department at Spain’s National Archaeological Museum, Salvador Rovira-Llorens. It was revealed in a paper published in January and suggests that metalworking technology and techniques in the Iberian Peninsula were far more advanced than previously thought over 3,000 years ago.
The Treasure of Villena, as the find of 66 predominantly gold objects is called, was discovered over 60 years ago, in 1963, in what is now Alicante in Spain and has since been considered one of the most important examples of Bronze Age goldsmith art on the Iberian Peninsula and in all of Europe.
However, determining the age of the collection was somewhat difficult due to two objects: a small, hollow hemisphere, believed to be part of a scepter or sword hilt, and a single torque-like bracelet. Both have an appearance that archaeologists have described as “ferruginous” – that is, they appear to be made of iron.
In the Iberian Peninsula, the Iron Age – when molten iron began to replace bronze – did not begin until around 850 BC. The problem is that the gold materials were dated to between 1500 and 1200 BC, so it was quite a puzzle to figure out where to place the iron-looking artifacts in the context of the Villena treasure.
But iron ore from the Earth’s crust is not the only source of malleable iron. There are a number of iron artifacts around the world dating to before the Iron Age that were forged from meteorite material. Perhaps the most famous is the meteorite dagger of the Pharaoh Tutankhamun, but there are other Bronze Age weapons made from this material that were highly prized.
There is one way to tell the difference: iron from meteorites has a much higher nickel content than iron dug out of the ground. So the researchers got permission from the Municipal Archaeological Museum of Villena, which houses the collection, to carefully examine the two artifacts and determine how much nickel they contained.
They carefully took samples from both artifacts and subjected the material to mass spectrometry to determine their composition. Despite the high level of corrosion altering the elemental composition of the artifact, the results strongly suggest that both the hemisphere and the bracelet were made from meteoric iron.
This elegantly solves the dilemma of how the two artifacts fit in with the rest of the collection: they were made around the same time period, i.e. around 1400 to 1200 BC.
“The available data suggest that the cap and bracelet from the Villena treasure are currently the first two pieces attributable to meteoric iron on the Iberian Peninsula,” the researchers explain in their article, “which is consistent with a chronology from the Late Bronze Age, before the beginning of widespread production of terrestrial iron.”
Because the objects are so heavily corroded, the results are not yet conclusive, but there are newer, non-invasive techniques that could be applied to the objects to obtain a more detailed dataset that would help corroborate the results, the team says.
The results were published in Works from prehistory.
An earlier version of this article was published in February 2024.
