Abrader manufactured from a dark gray basalt, with five "u" shaped grooves across its width. The grooves vary slightly with the deepest and widest groove being located in the center of the abrader. Striations run the length of each groove. The abrader's margins are relatively even and pecking scars remain visible on three of the corners. The base is flat and even with a shallow "v" shaped groove running at an angle across one end. Cylindrical holes on either end of the base were drilled historically. This abrader was located on the platform mound at the site of Pueblo Grande. Pueblo Grande was a large village located at the headgates of a major canal system. Occupied as early as AD 500, the site reached its greatest extent during the Classic Period. Museum Accession: 1992.19