AN ANALYSIS OF HOCKING VALLEY, OH POTTERY USING X-RAY DIFFRACTION, X-RAY FLUORESCENCE, AND OPTICAL PETROGRAPHY

The Allen Site, located near Athens in the Hocking River valley of SE Ohio, is a multilevel, Woodland / Fort Ancient site dating from ~6000BP to ~600BP. The site contained a variety of ceramic artifacts that were associated with periods of occupation radiocarbon dated to between 1300 BP and 700 BP. A total of 247 potsherds were recovered, most of which are small and in poor condition. Eight representative sherds were studied. Six of these are visually very similar, but two stand out as morphologically different. One sherd is redder and more fine-grained than the rest, and a second exhibits deep gray color and large angular inclusions. Distinct decoration on the outside of the gray piece suggests it may be Fuert in origin, associated with the later Fort Ancient phase, and perhaps suggests a shift in cultural behavior.

The main objective of this study was to use bulk chemical, mineralogical, and micro-morphological analyses of clays and inclusions in order to 1) distinguish pottery types from each other, and 2) to link pottery types to local clay sources. We used x-ray diffraction (XRD), x-ray fluorescence (XRF), and optical petrography to analyze the eight sherds included in this study. We also used the same techniques to analyze 3 local clay sources: a ~305 M.Y. paleosol from the Upper Glenshaw Formation, an early Pleistocene clay associated with the Teays river system, and a lacustrine clay likely dating to the Late Wisconsin.

XRF and optical petrography yielded the most promising results. Bulk chemical studies of the matrix suggest that the same source clay was used among all the sherds. A calcium peak present in the sherds and in the Teays clay is lacking in the other two clay sources, and presently points to the Teays as a likely source of raw material. The suspected 'Fuert' piece contains large angular inclusions that vary compositionally, do not appear to have been deposited naturally, and are not present in any other pieces. This may suggest the inclusion of a temper, and therefore a different manufacturing technology. This work, although presently limited in scope, shows great potential for the combined use of XRF and micro-petrographic analysis in the study of archeological pottery both in terms of distinguishing pieces from each other, understanding production techniques, source material locations, and possibly trade practices.