Long-distance jade exchange, linguistic boundaries, and migration in pre-contact western Canada

Nephrite (jade) was used for over 3000 years in western North America to make ground stone celts, some of which were transported over one thousand kilometers across boundaries of Indigenous languages and ecological regions. We employ archaeometric means to confirm nephrite identification and plot all known archaeological occurrences east of the Rocky Mountains. Nephrite celts are among the most widely dispersed artifacts in pre-contact Canada but lack clear utilitarian value in the regions to which they were moved. We link their distribution to an interaction sphere in British Columbia that fueled the exchange of coveted goods. Migration of foreign people through a nephrite production center, combined with local patterns of alliance building at forested boundaries, may explain long-distance jade exchange. On a regional scale, jade tools are proxy indicators of cultural change and new relationships. On a continental scale, jade artifacts denote immense social networks that transcended linguistic divides.