Trace‐element analysis of native copper: The view from Northern Minnesota,USA

Native copper, both finished artifacts and worked pieces, are relatively common in pre‐Contact sites of northeastern Minnesota. Fifteen artifact samples and seven sources of native copper were submitted for trace‐element analysis as a test of the procedures developed by G. Rapp, Jr. and colleagues (2000). Although the specific sources chosen had high typicality probabilities, very low posterior probabilities preclude confidence that the artifacts were accurately sourced. Potential problems include incomplete characterization of several sources, as well as the limited number of sources in the database. Of more interest than identification of specific sources is the selection of apparent source pairs. Michipicoten (eastern Lake Superior) and Isle Royale (western Lake Superior) are often chosen together; Weyerhauser Mine (Wisconsin) and the Champion Mine (Keewenaw Peninsula) may form another pair. Future research should concentrate on identifying patterns of sources in the region rather than focusing on specific mines. © 2007 Wiley Periodicals, Inc.