Experimental and archaeological verification of an index of retouch for hafted bifaces

`The relative amount of retouch on stone tools is central to many archaeological studies linking stone tool assemblages to broader issues of human social and economic land-use strategies. Unfortunately, most retouch measures deal with flake and blade tools and few (if any) have been developed,for hafted bifaces and projectile points. This paper introduces anew index for measuring and comparing amount of retouch on hafted bifaces and projectile points that can be applied regardless of size or typological variance. The retouch index is assessed initially with an experimental data set of hafted bifaces that were dulled and resharpened on five occasions. The retouch index is then applied to a hafted biface assemblage made from tool stone that has been sourced by X-Ray Fluorescence (XRF). Results of both assessments show that the hafted biface retouch index (HRI) is effective for determining the amount of retouch and the degree to which the hafted bifaces have been curated.