(CN) — During the Bronze Age, beginnings of modern society began to emerge: Tool use expanded, agriculture replaced wild food, and people developed systems to trade money.
The practice of using money dates back to the Early Bronze Age of Europe, which lasted from 2150 to 1700 BCE, according to a new analysis of thousands of standardized copper objects discovered north of the Alps.
Researchers described the object shapes as rings, ribs and axe blades, and ran a statistical analysis to assess the uniformity of each object’s size.
Though the objects’ weights varied, around 70% of the rings — and subsets of the ribs and axe blades, too — were indistinguishable to humans weighing them by hand, indicating they were used as currency.
Each ring weighed around 195.5 grams, but the uniformity was set by casting the metal in molds, rather than assigning a target weight to each ring.
Describing and comparing each of more than 5,000 objects, the researchers present their findings in a study published Wednesday in the journal PLOS ONE.
Maikel H. G. Kuijpers, an assistant archaeology professor at Leiden University in the Netherlands, led the study of the “oldest known form of money from prehistoric Europe.”
Before coins, the objects were “commodity money,” Kuijpers explained in an email. Their value came from the copper material itself, rather than each shape being assigned a specific worth.
As human civilizations expanded during the Bronze Age, materials like bronze and copper “helped this development along,” Kuijpers said, particularly because the metals could be cast in molds to create many copies of a given shape.
Beyond their function as money, bronze and copper changed the way societies perceived value, Kuijpers noted: “Materials help us think!”
The new paper settles a discussion about whether the copper objects were really a type of proto-currency, as had been suggested by some previous research.
“There was lots of discussion, but we lacked a proper methodology to test this idea,” Kuijpers said, adding that the new publication “provides definite evidence that we are dealing with commodity money.”
Kuijpers and colleagues used a psychology principle called the Weber fraction to determine that a human weighing the rings and ribs by hand would not be able to tell the difference between each. (Without scales, it’s likely that weighing by hand was the only option.)
The axes, the team found, were likely a regional currency. They seem to be compatible with rings and ribs, often discovered together, or tied to each other.
By the end of the Early Bronze Age, rings and ribs were already passé. They were replaced by scrap metal and pieces of casting cakes. As the first scales were created in Western Europe, during the Middle Bronze Age, currency standardization could become even more accurate.
Thousands of years later, money itself certainly has not fallen out of style. Learning more about the origins of currency helps researchers understand the important role of money to humans, from early civilization to the dawn of Bitcoin and other cryptocurrencies.
The copper currency research is part of a project to study a peculiar practice throughout ancient Europe: Valuables, like bronze objects, were buried or thrown into rivers, uncovered later by researchers.
Kuijpers is studying this systematic destruction of valuable metals to better understand ancient cultures, and how destroying these items may have created their value.
“So,” he said, “we are looking at a society with an economy that looks familiar and unfamiliar at the same time.”
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