Exchange, Interactions, and Technological Practices in the upper Great Lakes c. 1630-1730
By: Dr. Heather Walder
This research addresses the timing of the introduction, exchange, and social implications of two complementary lines of evidence, reworked copper and brass objects and glass trade beads, from 38 archaeological sites of the Upper Great Lakes region dated to c. 1630 to 1730. In this situation of intercultural contact and colonialism, local Midwestern Native peoples encountered European-made trade items, displaced Native newcomers, and eventually non-Native explorers, traders, and missionaries. Anthropological questions of regional interaction, technological continuity and change, long-distance trade, and population mobility are the focus of this project, which has identified material correlates for the chronology and scope of socially-structured exchange networks that facilitated intercultural interaction.
I applied elemental characterization and attribute analysis methods that revealed how long-standing technological practices, such as native copper-working, persisted through time and what techniques people developed to adapt to new materials, allowing me to build inferences about the social significance of these technologies. Laser Ablation – Inductively Coupled Plasma – Mass Spectrometry (LA-ICP-MS) was used to identify the “recipes” of 874 glass adornments, which revealed chronological change in glass-making technology in Europe and Native glass reworking methods in North America. A portable X-Ray Fluorescence (pXRF) pilot study and physical attribute analysis of 3,705 copper-base metal artifacts such as beads, tinkling cones, other ornaments, partially worked blanks, and waste products revealed patterns in types and styles of finished objects, the mean size of discarded materials, and continuity of technological practice over time. The project verified pXRF as a viable technique for differentiating native and smelted copper without any cleaning of corroded artifacts.
Conducting new laboratory-based analyses on previously excavated artifacts has enhanced the value of existing collections and highlights the importance of long-term curation strategies for artifacts as well as associated excavation records, maps, and other primary documentation of provenience information and recovery methods. Together, metal and glass analyses demonstrated that the diverse peoples inhabiting the Upper Great Lakes region accessed different quantities and kinds of trade items, and that the trade items themselves and technological methods applied to them varied through time, across space, and according to the historically-attributed ethnic identity of communities.