Evaluating the usefulness of phytoliths and starch grains found on survey artifacts

Archaeologists use survey artifacts to study any number of interesting topics. The focus of this study is to test the usefulness of starch grains and phytoliths found on artifacts recovered during archaeological survey. Phytolith and starch grain analysis was used to determine the level of environmental contamination on three types of medieval ceramics collected during survey work from plowed fields in the parish of Wicken, Northamptonshire, England. The plant residues found on these artifacts were compared with their surrounding soil and with contemporaneous excavated artifacts recovered from under the floorboards of a medieval house in nearby Wyton, Cambridgeshire, England. Through the use of the piggyback approach pioneered by Chandler-Ezell and Pearsall, phytoliths and starch grains were systematically removed from the artifacts surface. Residues associated with contamination were removed from the outermost layer of the artifact surface while potentially uncontaminated residues were removed from the innermost layer of the artifact surface. Matching phytoliths and starch grains were found on the outermost surface of the survey artifacts and in the surrounding soils. No phytoliths and starch grains were found on the innermost surface of the survey artifacts suggesting that residues from the surrounding soils did not penetrate into the pores and crevices of the artifacts. The overall results suggest that, although they are preliminary, there is potential for plant residue analysis of survey artifacts. (C) 2011 Elsevier Ltd. All rights reserved.