Learning from blind tests: determining the function of experimental grinding stones through use-wear and residue analysis
Blind tests provide an objective means to evaluate the accuracy of functional interpretations based on the presence of use-wear and residue traces on stone tools. Previous blind tests have highlighted interpretive errors commonly associated with use-wear and residue analyses leading to significant methodological developments in each of the respective fields. While a number of blind tests have been performed on flaked stone tools, only a single blind test has been published for use-wear on grinding tools. We present the results of a two-part blind test performed on 15 experimental grinding implements that were used in a controlled setting, designed to evaluate the relative importance of residue analysis for determining the worked material (1) when contextual information is available and (2) when contextual information is absent. We argue that use-wear and residue analyses are successful procedures to identify the use of grinding stones, and that residue analysis may be a particularly valuable means for determining the worked material on tools that have insufficient use-wear development. We suggest that residues should be sufficiently abundant to infer use, if we are to avoid the potential confusion caused by contamination.