Knapping quality of local versus exotic Upper Mercer chert (Ohio, USA) during the Holocene

Stone that fractured conchoidally was an important resource for prehistoric hunter-gatherers. In recent years, archaeologists have come to realize that rather than defining stone “quality” simply and implicitly as “high” or “low,” a stone's quality can be best defined in several different explicit and often quantitative ways involving production, function, or social benefits. Here, we examine the stone quality—defined as “fracture predictability”—of Upper Mercer chert when it is locally versus nonlocally acquired by prehistoric people in Ohio, USA. By quantitatively assessing silicon dioxide (SiO₂) content and loss on ignition, we compared stone tools from a site at the Upper Mercer outcrop (n = 42) to those found at archaeological sites over 100 km north of it (n = 126). Our results showed that the former on average were of significantly higher quality than the latter. We conclude with a consideration of factors that could cause this difference in quality, suggesting that the lower quality of Upper Mercer chert in northern Ohio might be explained by northern people's decreased familiarity with it during the Archaic period and by their decreased access to it during the Woodland and Late Precontact periods.