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NO, I’M NOT making a political comment about policing in the U.S. Upper Midwest. Rather, I’m citing “Great Lakes People Among First Coppersmiths,” as reported by David Malakoff in Science magazine, March 26, 2021.
Malakoff notes, “A new study concludes that one of the world’s earliest metal working cultures emerged, and then mysteriously faded, far earlier than once thought. The Old Copper Culture, known for using copper to craft projectile points, knives, axes, and other tools, flourished around North America’s Great Lakes more than 5000 years ago.”
Here are tidbits gleaned from this AAAS Science article.
Previous Thinking on the Matter. Hitherto, Malakoff writes, “When researchers began to date the artifacts and mines, they saw a perplexing pattern: The dates suggested the people of the Old Copper Culture began to produce metal tools about 6000 years ago and then, for reasons that weren’t clear, mostly abandoned copper implements about 3000 years ago.”
It’s unknown why these people turned away from all but ornamental use of copper and reverted to tools of stone and bone.
A Revised Timeline. Ten years ago, geologist David Pompeani at Kansas State University, Manhattan, began questioning this previous timeline. Writes Malakoff, “He extracted sediment cores from lakes adjacent to prehistoric mines on Michigan’s Keweenaw Peninsula and Isle Royale and measured trace metals in the cores, including lead and titanium, that had been released by processing the ore.”
Note the similarity of his research path to that reported in “Is That What’s Troubling You, Bunkie?” There, researchers deduced good and bad pre-medieval times by analyzing the levels of lead leftover from silver smelting.
This time around, Malakoff says Pompeani’s “analyses showed copper mining began about 9500 years ago in some areas—some 3500 years earlier than once thought. It also ended earlier, about 5400 years ago, Pompeani reported in The Holocene in 2015.”
The Latest Approach. Pompeani and his colleagues “used modern methods to reanalyze 53 radiocarbon dates—including eight newly collected dates—associated with the Old Copper Culture. Some came from wood or cordage still attached to spearpoints; others came from charcoal, wood, or bone found at mines and human burials. The oldest reliably dated artifact turned out to be the 8500-year-old projectile point found in Wisconsin,” Malakoff says.
Why Revert to Stones? Michelle Bebber, Kent State University, is a specialist in Old Copper Culture. To study the question of why this culture eschewed copper, she replicated these tools and compared them to those of stone and bone used for the same purposes.
Malakoff writes, “In controlled laboratory tests, such as shooting arrows into clay blocks that simulate meat, she found that stone and bone implements were mostly just as effective as copper.”
That is, there was little reason to mine and smelt when alternative materials were there for the asking.
Malakoff observes, “That might be because Great Lakes copper is unusually pure, which makes it soft, unlike harder natural copper alloys found elsewhere in the world, she says. Only copper awls proved superior to bone hole punchers.”
Climate Disruption. Malakoff says, “Pompeani has identified another potential contributor to Old Copper’s fade about 5000 years ago. Sediment cores, tree ring data, and other evidence suggest a sustained dry period struck the region around that time, he says. That could have fueled social and ecological disruptions that made it hard to devote time and resources to making copper tools. Over time, copper may have become something of a luxury item, used to signal social status.”
It reminds me of a later age’s (our current one’s) assessment of the Stone Age: The Stone Age didn’t end because of a lack of stones; it ended because something better came along. Similarly, our Fossil-Fuel Age may well end, despite the existence of these resources. ds
© Dennis Simanaitis, SimanaitisSays.com, 2021