Analyses of the distribution and nature of abrasion on ceramic rings from the third millennium BC portion of the Godin III pottery assemblage in western Iran (2600-1400 BC) indicate that it represents use wear. Residual scars on pottery vessels and reconstruction of vessel-forming sequences support identification of these rings as potter's tools. They provide interconnections among varied sizes of Buff Common ware vessels made using different forming and finishing methods. This strengthens the inference of workshop production by specialist potters who make the full range of Buff Common ware vessels.