A striking or shaping tool structured to size and/or otherwise shape an object such as, but not limited to a jewelry object, which is mounted on a mandrel. The tool comprises a generally hammer-like construction including a head having a base. A striking member, having a striking surface, and an alignment member are connected to the base and are cooperatively dimensioned and disposed. The striking member also includes a mandrel engaging portion comprising one or more recessed, exposed surfaces dimensioned and configured to substantially conform to an exterior surface of the mandrel. The cooperative dispositions and dimensions of a recessed exposed surface and the alignment member facilitate a concurrent, movable engagement thereof with the mandrel during a striking procedure of the striking surface on the mandrel mounted jewelry object, resulting in a predetermined operative orientation of the striking surface relative to the jewelry object, during the striking procedure.