Bronze Age artefacts made from meteorites

You may be impressed to hear that there are iron objects in existence today that date back to the Bronze Age, but their meteorite origin is even more astonishing.

The Iron Age began in Anatolia and the Caucasus around 1200 BC. But nearly 2000 years earlier, during the Bronze Age, various cultures were already fashioning objects out of iron — items that were extremely rare and always greatly treasured.

So what made these artefacts so valuable, especially since iron ore abounds on the Earth’s surface? Research has shown that some Bronze Age artefacts were made with iron from meteorites, which led scientists to wonder whether they accounted for most of these artefacts or simply a few. Albert Jambon, as part of his work at the Institut de minéralogie, de physique des matériaux et de cosmochimie, gathered the available data and conducted his own non-destructive chemical analyses of samples using a portable X-ray fluorescence spectrometer.

Jambon’s collection of iron artefacts includes beads from Gerzeh (Egypt, 3200 BC); a dagger from Alaca Höyük (Turkey, 2500 BC); a pendant from Umm el-Marra (Syria, 2300 BC); an axe from Ugarit (Syria, 1400 BC) and several others from the Shang dynasty (China, 1400 BCE); and the dagger, bracelet and headrest of Tutankhamen (Egypt, 1350 BCE). Published in the Journal of Archaeological Science, his analysis reveals that each of these artefacts was made with meteoric iron — and explains the reason why.

When large celestial bodies like our planet are forming, nearly all nickel drifts towards the molten iron core. Thus, it is extremely rare to find nickel on the surface. However, some meteorites are created when celestial bodies are shattered. If these meteorites are composed of core material, they mostly contain iron with high levels of nickel and cobalt. This characteristic makes it possible to identify the source of iron. Meteoric iron is also already in a metal state, ready for use, which explains why it went into all Bronze Age iron artefacts.

In contrast, the iron compounds in terrestrial ores must first undergo the process of reduction, which removes bound oxygen to yield the desired metal. This is the basis of smelting in furnaces — a breakthrough that marked the beginning of the Iron Age. With smelting, Iron Age cultures could forget rare extraterrestrial metal and tap into terrestrial iron ores, which were far more abundant and easier to procure.

Jambon’s findings thus demonstrate that iron used during the Bronze Age is always meteoric, refuting certain theories that nickel-laden iron alloys were obtained from terrestrial ores.

Image credit: ©stock.adobe.com/au/Romolo Tavani