Intact artifacts and features found at the Powars II site, a red ocher (also known as hematite) quarry located in the foothills of the southern Rocky Mountains in Wyoming, demonstrate unequivocal evidence for red ocher quarrying by Paleoindians beginning 12,840 to 12,505 years ago, thus establishing Powars II as the oldest red ocher quarry identified in the Americas.
Red ocher fulfilled a wide range of functions in Paleoindian societies, including as a pigment in rituals, and is present in a relatively large number of early Paleoindian sites in North America.
The Powars II site, located in the Hartville Uplift of southeast Wyoming, is the only red ocher quarry identified in the North American archaeological record north of southern Mexico and one of only five such quarries identified in all of the Americas.
After being collected by Wayne Powars in the early 20th century and revealed to archaeologists in the 1980s, the site was almost destroyed during mine reclamation in 1986 but was saved in part by efforts of archaeologists, who briefly documented the site over several days in 1986.
Among the artifacts previously discovered at the site are Clovis points — believed to be from the first inhabitants of North America — along with other projectile points, tools and shell beads.
“We have unequivocal evidence for use of this site by early Paleoindians as long as 12,840 years ago and continuing by early Americans for about 1,000 years,” said Wyoming State archaeologist Spencer Pelton.
Between 2017 and 2020, Dr. Pelton and colleagues excavated a 6 x 1 m trench bisecting a previously undocumented quarry feature at Powars II.
This excavation documented a combination of intact and redeposited site sediments primarily comprising anthropogenic quarry tailings containing several thousand Paleoindian artifacts as well as many well-preserved animal bones and antlers. The animal bones and antlers were used to extract the red ocher in the quarry.
The projectile points came from numerous locations in the region, including from as far away as the Edwards Plateau in Texas.
That makes it likely that red ocher found at archaeological sites throughout the American midcontinent came from the Powars II quarry.
“Beyond its status as a quarry, the Powars II artifact assemblage is itself one of the densest and most diverse of any thus far discovered in the early Paleoindian record of the Americas,” Dr. Pelton said.
“The site contains over 30 chipped stone tools per square meter, some of the oldest canid remains from an American archaeological site and rare or unique artifacts, among other distinctions.”
The evidence discovered so far indicates the Powars II quarry was used in two primary periods.
During the first, dating to as long as 12,840 years ago and lasting several hundred years, people not only quarried red ocher — using bones and antlers as tools — but also produced and repaired weapons, along with other activities.
After a hiatus of a century or more, the site was occupied by humans who mined red ocher and deposited artifacts in piles in a quarry pit.
“Further excavation of the estimated 800-square-meter remainder of the site will certainly reveal complexity not captured by our sample,” the authors said.
A paper describing the findings was published in the Proceedings of the National Academy of Sciences.
Spencer R. Pelton et al. 2022. In situ evidence for Paleoindian hematite quarrying at the Powars II site (48PL330), Wyoming. PNAS 119 (20): e2201005119; doi: 10.1073/pnas.2201005119