For scratches to polished crowns and buckles we recommend using Autosol cream as a DIY option. Autosol not only finely abrades the metal, it also removes oxides and dirt. We recommend putting a tiny amount of Autosol onto a soft cloth, stretching it between your fingers and then, holding the whole watch, rubbing the crown in a circular motion into the cloth. You will notice a dark mark appearing on the cloth. Then move to a clean part of the cloth and repeat.