The iron of the Bronze Age was meteoritic
Protohistory was characterized by the Age of Copper, then the Bronze Age and finally the Iron Age. Each age, as its name indicates, bearing the mark of the mastery of specific metals and of the technical progress resulting from it. Yet, researchers have kept finding objects made of iron dating to the bronze age…
Recent discoveries have shown that this iron actually came from meteorites. This had been known before, as in the case of Tutankhamun’s dagger, but the scientific community didn’t know if this was true of all the objects or if this was only an exceptional occurence.
The question has been resolved by French researcher Albert Jambon, at the Centre National de la Recherche Scientifique’s Institute of Mineralogy, physics of materials and cosmochemistry. Thanks to his investigations, published in the December edition of the Journal of Archaeological Science, he was able to prove that iron used in the Bronze Age was systematically of exoterrestrial origin, as well as to explain why the earlier technology of using iron had disappeared in the iron age.
In a communiqué published on December 1st, the CNRS reminds that the Iron Age started in Anatolia and in the Caucasus around 1200 BC. Yet, almost 2,000 years earlier, varied cultures were already making objects out of iron. Early research found that some had been made with iron coming from meteorites.
This discoveries convinced Albert Jambon to carry out research to determine how great a share of these relics were actually of exo-terrestrial origin. The scientist first looked up already available data, then carried out his own, non-destructive research with the help of specialized tools. He analyzed :
- iron beads found in Gerzeh (Egypt, 3200 BC)
- a dagger found at Alaça Huyuk (Turkey, 2500 BC)
- a pendant from Umm el Marra (Syria, 2300 BC)
- an ax from Ugarit (Syria, 1400 BC)
- several objects from the Shang dynasty (China, 1400 BC)
- the dagger, the bracelet and the headrest of Tutankhamun (Egypt, 1350 BC).
- several objects of Shank Dynasty (China, 1400 BC),
The result : all these artefacts were indeed made of meteoritic iron.
In order to understand how the scientist was able to determine that he was dealing with exoterrestrial iron, one must point out that when the Earth was formed, another metal, nickel, migrated almost wholly towards the liquid iron core. Nickel is therefore very rare at the surface of Earth. But some meteorites originate in the destruction of planets. If they are a fragment of their core, they are made up principally of iron which is very rich in nickel (as well as in colbalt). This makes it possible to determine whether the iron is coming from Earth or from a meteorite.
Why then does the Bronze Age bear its name, if its artisans were already able to work iron ? In fact, iron present in meteorites is already in a metal state, and therefore can be used directly. On Earth, iron comes from ore – rocks – which must first be transformed in order to extract the metal and remove the oxygen. And this technique was mastered by humans only in the… Iron Age. At that time, the very rare exoterrestrial metals were abandoned in favor of the abundant terrestrial iron ores.
Victor Garcia, L'Express, Dec. 2, 2017
translated from the French by Anne-Marie de Grazia