How could people living during the Bronze Age pull off the difficult process of making iron? They didn't, concludes a new study; instead, they got the iron for the rare iron artifacts discovered from the period in an easy-to-use form: meteorites hitting Earth.
     There have always been rare objects made of iron long before the Bronze Age faded. Archaeologists have been stumped by these objects because iron is much more difficult to process than bronze, and they didn't think any Bronze Age civilizations had the skills needed to do so.
     Albert Jambon, a mineralogist at the Pierre and Marie Curie University in France, tackles these weird early iron exceptions in a paper, published in the Journal of Archaeological Science. Jambon wanted to determine plausibility that there was some, as he describes it in the paper, 'precocious smelting' of iron during the Bronze Age.
     So Jambon tracked down the early pieces of iron that popped up during the Bronze Age, when iron was more valuable than gold. Those included a Syrian ax made around 1400 BCE and bracelets found in Poland from about 700 BCE.
     Then, he analyzed those items, looking at ratios of the elements iron, cobalt and nickel to evaluate the iron's origins and found that everything before about 1200 BCE seemed to come from meteorites. Iron from meteorites is much harder to track down than terrestrial iron, but it's much easier to process. That means that while it was certainly a luxury item because of its rarity, it doesn't represent a previously unknown technological advance.
     Pre-smelting iron artifacts made from meteorites have been discovered around the world, including in Greenland, eastern North America and Tibet.

Edited from Newsweek (4 December 2017)