Try Zud, an abrasive cleanser available in supermarkets and hardware stores. Heavy rubbing with Zud removes superficial scratches. However, it might dull a mirror finish. Test it out first on old flatware.
Before Zud
After Zud. Before rubbing, piece was laid on a soft cotton rag, and then heavy rubbing was applied.
After Zud. Before rubbing, piece was laid on a soft cotton rag, and then heavy rubbing was applied.
