Rock surface hardness as an indication of exposure age: An archaeological application of the Schmidt hammer

A Schmidt Hammer was employed in evaluating the surface hardness of rocks which line ancient anthropogenic pit features, known as Pukaskwa pits, on the north shore of Lake Superior, Canada. This technique offers a possible new method of producing relative and absolute dates for such exposed stone features. Analysis of the data has provided a relative chronology for the pit features, representing two distinct construction phases. The range of absolute dates generated from the data indicates that the pits were likely constructed by Blackduck peoples c900 to 400 years BP.