An aqueous electrolyte solution including a concentration of citric acid in the range of about 1.6 g/L to about 982 g/L and an effective concentration of ammonium bifluoride (ABF), and being substantially free of a strong acid. Methods of micropolishing a surface of a non-ferrous metal workpiece including exposing the surface to a bath of an aqueous electrolyte solution including a concentration of citric acid in the range of about 1.6 g/L to about 780 g/L and a concentration of ammonium bifluoride in the range of about 2 g/L to about 120 g/L and having no more than about 3.35 g/L of a strong acid, controlling the temperature of the bath to be between the freezing point and the boiling point of the solution, connecting the workpiece to an anodic electrode of a DC power supply and immersing a cathodic electrode of the DC power supply in the bath, and applying a current across the bath.