A drive plate for a concrete or stone grinding/polishing machine includes one or more abrasive elements in the form of short sintered metal bars having diamond crystals mixed therein. Due to the triangular profile of the abrasive elements, as the drive plate is rotated by a drive motor and the apex of the triangular abrasive element engages the floor surface being treated, the abrasive elements are able to more readily strip off mastic, sealers, glue, or most any thin film topical coating present on concrete or other hard floors.