This copper knife is from the Archaic period, which saw the earliest human use of Isle Royale. It was found during a 2013 excavation along the Isle Royale's ancient Nipissing shoreline, which peaked near 5,000 years ago. Radiocarbon methods have dated this site to approximately 3730 years before present (ybp)making it the oldest known occupation site on Isle Royale. , Older Archaic dates, ca.
4500 ybp, have been identified on Isle Royale. These are associated with mining pits where indigenous people extracted native copper from bedrock fissures found island-wide. In all likelihood, the knife was produced from copper gathered from one of these sources. In 2014 the copper knife was submitted for protein residue analysis, which resulted in evidence that the knife was once used to kill or process animals related to the order rodentia (beaver/squirrel) or possibly the canidae order (fox/coyote/wolf).
Native copper is found on both Isle Royale and the nearby Keweenaw Peninsula which are both part of the same geologic formation. Although glacially transported copper, such as float copper, is found elsewhere in the Lake Superior basin, reliable sources are much harder to come by. Isle Royale has bedrock fissures that provide an extractable source of copper. Native American peoples recognized the inherent value of copper, its qualities and potential. As early as 4500 ybp they took great risk crossing in canoes from the mainland's north shore to Isle Royale. They travelled to the island seasonally, and returned in canoes laden with copper, to be utilized and traded as a commodity among indigenous cultures