Characterization and origin of steatite beads made by Northern Iroquoians in the St. Lawrence Valley during the 15th and 16th centuries
Résumé
Since Precontact times, First Nations' groups from northeastern North America used steatite to make many artifacts, such as ornaments and vessels. Only a few studies have been dedicated to this topic, such as on steatite vessels from northern Dorset sites and from Eastern North America. In these regions, steatite vessels are common. In the regions occupied by Iroquoian groups during the Late Woodland period in the St. Lawrence Valley, many beads and some pipes have been discovered but steatite vessels are nonexistent. Steatite quarries are known for steatite vessels, but not for the Iroquoian region. Consequently, tracing the geological origin of steatite materials and the distribution of artifacts represents a scientific challenge. The aim of both archaeological and geological approaches is to define the origin of materials via a precise and accurate geochemical characterization. Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) was chosen for its micro-destructive feature, and provides a precise measure of the chemical composition of the materials. The results presented here have allowed us to highlight the use of steatite from only carbonate rocks and not steatite hosted in ultramafic rocks, which is different from most of the previous studies. Moreover, relationships between a limited number of sources and some archaeological artifacts have been identified.