The artifacts of obsidians discovered in Alberta offer new clues on prehistoric commercial routes
Black fragments of volcanic glass inks discovered in Alberta are helping researchers to trace the movements of the natives in the centuries ago of western Canada.
Hand carved arrow and jagged oxidian lance, an acute rock formed by volcanic magma, are remains of vast prehistoric commercial networks that once cross western North America.
No volcano has ever burst in Alberta, which means that every fragment of Obsidian found in the province was transported here. With X -ray technology, researchers can trace each piece to its source.
A new document that examines artifacts discovered by the eastern slopes of Alberta suggests that hunting for bison in the southern feet and a vast exchange network along the rivers of the north of the province have contributed to distributing the stones throughout the province.
The archaeologist Timothy Allan, the author of the report, said he wanted to better understand the role of Alberta in a vast indigenous commercial network that once has crossed more than three million square kilometers.
A single piece of obsidian has probably changed his hands many times.
“The scope of the oxidian trade tells us that probably millions of people were in contact with each other,” said Allan, who works with Ember Archaeology, a consultancy company for archeology and historical resources based in Sherwood Park, Alta.
“The area of the commercial network was much more enormous than we thought.”
Understanding the travels of the artifacts of obsidian can provide new information on how people have moved through the landscape and the complex cultural ties that modeled the continent centuries ago, said Allan.
“It is certainly part of our role in reconciliation, as archaeologists, to help tell these stories”.
The research, published by The Archaeological Survey of Alberta, is the last offer of the Obsidian Alberta project, a collaboration being researchers and archaeologists who examine the vast obsidian record in the province.
Chemistry sealed over time
In the last decade, the researchers of the project have studied and cataloged over 1,200 artifacts of oxidians Alberta.
The artifacts and the trade itself date back to a period between 13,000 and 300 years ago, before European contact.
More than 520 archaeological sites have been identified in the province. The oriental slopes, which extend from the alpine slopes of the rocky mountains to the feet, offer the largest number of samples.
Fragments were found in 285 archaeological sites in the region. Allan’s analysis examined 383 specimens from 96 sites.
Obsidian’s unique qualities made him precious for prehistoric peoples who used him and for archaeologists today.
The most acute material in natural material on Earth was appreciated by the indigenous populations that sculpted it in cutting tools and weapons.
Each piece of oxidian, formed by volcanic magma, has a unique chemical signature. Using X -ray fluorescence, researchers can identify unique geochemical markers and confirm the origin of each piece.
“It is formed when a volcano explodes and lava cools very, very quickly,” said Allan. “Because it cools so quickly, seal its chemistry over time.”
Each piece is a test in good faith of a long distance exchange in the past, Allan said.
“If you find Obsidian, you know that material has traveled a lot.”
Distinct commercial routes
Alberta said Alberta seems to be the northern edge of the commercial network, which has extended through the American Midwest until the south of Texas, and in Canada north of what is today Fort McMurray, high.
The artifacts found in Alberta traveled between 400 and 1,200 kilometers, with the vast majority from Bear Gulch in Idaho and Obsidian Cliff in the Yellowstone of Wyoming National Park. Other sources include the sites of Anahim Peak and Mount Edziza in BC
Bear Gulch’s samples represented 62 % of all samples. Examples of obsidian cliffs formed about 30 %.
But the data suggest that the commercial routes were distinct from each other, with the North Saskatchewan river and the Red Deer river that served as natural boundaries between the commercial routes.
People in what are today the northern Alberta were more connected to the tribes to the west, while people in the south were more closely linked with other tribes who lived in the open plains of the southern feet.
In the north, the trade seems to have been more sporadic, with the obsidian who probably moved to Alberta from BC along the large networks of the East-West river that crossed the rocky mountains.
To the south, the hunt for the common bison seems to have shaped the trade.
Obsidian in these regions has been exchanged in relatively larger quantities and exchanges seem to be part of a large social network shared by people who lived and collected together in the plains of what is now the south of Alberta and the American Midwest.
Much of the Ossidian discovered in the south of the Alberta comes from sources south of the border. The jumps of the bison – where the herds were driven out by the cliffs during large hugs – represent some of the highest concentrations of obsidian artifacts in the province.
A portal in the past
Todd Kristensen, a regional archaeologist of the Archeological Survey of Alberta, said that the data eliminated significant models on how people shared the earth and resources.
“We can use obsidian to understand how several indigenous groups in different ecological regions have adapted differently to the landscape,” said Kristensen.
“It’s one of those small portals that we can use to understand how people have adapted.”
Alberta’s obsidians record is univocally positioned to provide a vision of the past. The research offers a rare look at the links between various indigenous peoples, said Kristensen.
He said that further research is needed to understand the cultural meaning of these prehistoric kinship connections – and the stone itself – between the indigenous populations.
“Obsidian is fascinating because he tells us about human relationships,” he said. “It is really rare that archaeologists can find.”
