Discovery of copper band shows Native Americans engaged in trade more extensively than thought

August 7, 2018, Binghamton University
Copper band revealed during excavations. Credit: Matthew Sanger

A research team including Matthew Sanger, assistant professor of anthropology at Binghamton University, State University at New York, has found a copper band that indicates ancient Native Americans engaged in extensive trade networks spanning far greater distances than what has been previously thought.

"Our research shows that Native Americans living roughly 3,500 years ago were engaged in extensive spanning far greater distances than we had previously assumed (more than 1,500 km) and across various regions that we did not know were connected (the Great Lakes and the coastal Southeast)," said Matthew Sanger, assistant professor of anthropology at Binghamton University. "While we still struggle to understand the nature of these trade networks, our findings suggest that they moved not only objects (such as the piece of worked copper we recovered) but may also be a pipeline through which belief systems, cultural values and societal norms were also exchanged. The possibility that information also traveled along trade networks is evidenced by the shared use of cremation found alongside the exchange of copper between the two regions."

Sanger and colleagues found a copper band, slightly wider than a bracelet, alongside the cremated remains of at least seven individuals at a burial site in coastal Georgia. Prior to their discovery, both copper and cremated human remains dating to the Archaic period (around 3,000-8,000 years ago) were rarely, if ever, found in the Southeast United States. The copper band and burials were located in the center of a Late Archaic shell ring—circular deposits thought to have been used by Native Americans as both residential sites and as places of ritual gatherings and feasting events. Radiometric dating using an Accelerated Mass Spectrometer indicate that the remains and band are both more than 3,500 years old. This is significant, as it pushes the practice of cremation, as well as the use of copper, in the region more than a millennium older than previously thought.

Remarkably, the copper band was not manufactured from local materials, but rather originated in the Great Lakes region, more than 1,500 km away. Copper sources each have their own unique chemical makeup, including very small amounts of trace elements. As such, archaeologists can match manufactured objects to their sources by comparing their chemical signatures, or "fingerprints." Using Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICPMS), researchers at Ball State, the Field Museum and the New Jersey State Museum determined the chemical makeup of the copper band was most similar to sources found near the Great Lakes. While archaeologists had long known copper was exchanged out of the Great Lakes region, the discovery made by Sanger and his colleagues extended previously documented boundaries of Archaic Period copper exchange by nearly 1,000 km.

Excavations recovering copper band from site in coastal Georgia. Credit: Matthew Sanger

The use of cremation is also notable, as this practice is virtually absent in the Southeast United States during the Archaic period, yet quite common further to the north, including in the Great Lakes, where the copper originated. The co-occurrence of use and cremation practices suggests, according to Sanger and colleagues, that these two regions were more closely linked than previously assumed. The possibility that the two regions shared cosmological worldviews or religious practices would suggest direct connections across huge amounts of space.

According to the authors, these findings lend insight on emergent patterns of hierarchical social organization in the Archaic Southeast United States.

"Defining social complexity is always difficult—but our research shows that people were organized to a degree that allowed the formation of vast trade networks spanning half of a continent more than 3,000 years ago," said Sanger. "Considering that these trade networks likely moved both information and objects, we argue that they were not simple "down the line" exchanges—meaning that objects would slowly move between people over large amounts of time, perhaps through trade between friends and neighbors or as inherited items when someone died. Rather, the movement of information across more than 1,500 km suggests that exchange networks were more formal and direct. Such formal and direct networks suggest sustained relations between diverse communities, which must have been sustained by relatively complex social institutions. We assume these social institutions were religious or ritual in nature considering that we are looking at a multiple-person cremation in the center of a circular deposit of food remains."

Sanger and his colleagues at the University of Georgia and Northern Kentucky University have recently been granted a $300,000 grant from the National Science Foundation to study an additional 12 shell rings. 

"With this grant, myself and my colleagues will begin an ambitious field program and associated analyses to determine whether our findings were unique or part of a broader pattern in the American Southeast," said Sanger.

The paper, "Early metal use and social organization in the southeastern United States," was published in the Proceedings of the National Academy of Sciences.

Explore further: Copper stearate promising for heavy oil oxidation, study says

More information: Matthew C. Sanger et al, Early metal use and crematory practices in the American Southeast, Proceedings of the National Academy of Sciences (2018). DOI: 10.1073/pnas.1808819115

Related Stories

Copper stearate promising for heavy oil oxidation, study says

July 27, 2018

Copper salts have found place in many industries from pharmaceuticals to agriculture, but they are rarely seen in petrochemistry and petroleum extraction. Now, Kazan Federal University scientists have showed that copper stearate ...

Scientists fill in a piece of the copper transport puzzle

February 14, 2018

Researchers have identified the protein that carries copper into mitochondria, where copper is required for the functioning of the cell's energy conversion machinery. The discovery, published in the Feb. 9 issue of the Journal ...

Recommended for you

Chinese Cretaceous fossil highlights avian evolution

September 24, 2018

A newly identified extinct bird species from a 127 million-year-old fossil deposit in northeastern China provides new information about avian development during the early evolution of flight.

Ancient mice discovered by climate cavers

September 24, 2018

The fossils of two extinct mice species have been discovered in caves in tropical Queensland by University of Queensland scientists tracking environment changes.

The first predators and their self-repairing teeth

September 24, 2018

The earliest predators appeared on Earth 480 million years ago—and they even had teeth capable of repairing themselves. A team of palaeontologists led by Bryan Shirley and Madleen Grohganz from the Chair for Palaeoenviromental ...

Fat from 558 million years ago reveals earliest known animal

September 20, 2018

Scientists from The Australian National University (ANU) and overseas have discovered molecules of fat in an ancient fossil to reveal the earliest confirmed animal in the geological record that lived on Earth 558 million ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.