Defining the provenance of red slipped pottery from Texas and Oklahoma by petrographic methods

Ceramics are among the most important artifacts that archaeologists use to reconstruct patterns of prehistoric trade and exchange. Petrographic analysis of ceramic thin-sections, in addition to providing detailed technological data, enables the identification of sand-tempering agents. These raw materials are potentially important evidence for ceramic provenance, assuming that such common materials themselves would not have been traded. Here we apply methods developed by sedimentary petrographers to the problem of determining the provenance of Red Slipped sherds from late Prehistoric ( c. AD 1000–1400) sites in the Caddoan area and contemporaneous Plains Village sites. Modal frequencies of different kinds of quartz, feldspars and lithic grains are used to construct several triangular graphs that reveal compositional patterns indicative of provenance. Sherds from the Plains Village sites exhibit higher frequencies of lithic grains, feldspars and polycrystalline quartz relative to the sherds from sites in eastern Texas and eastern Oklahoma. While anomalous sherds were identified, the longstanding assumption that Red Slipped sherds in Plains Village contexts were traded from the Caddoan area is not supported by these data. These methods have strong application potentials for other, geologically diverse portions of North America.