It's polished, as in polished bright on a buffing lathe? If the corrosion is very shallow, some 0000 steel wool, followed by polishing. If it's deeper, I've had good results using a blue (fine) Nyalox wheel (nylon bristles impregnated with abrasive-- it's very gentle and controllable compared to metal wire) turned no faster than about 1750 RPM or the nylon overheats. If it's too deep for that, sandpaper it. I like 400 grit carbide, dry, followed by 600 grit carbide paper with oil, followed by buffing for a bright finish. On steel, the oiled papering gives you pretty close to a bright polished surface all on its own. For satin, the 600 paper, dry, and/or 0000 wool is plenty good. There is a carbide abrasive-coated mesh strapping material that works very well also, and I use it a lot on steel to remove small pitts and scratches.
Never try to buff out any but the smallest of pits on a buffing machine. You remove them with the abrasives first, then buff (for the really nasty stuff, I use a file, then sandpaper, then buff). Otherwise you just end up smearing the pits into larger pits and troughs. As you buff, you must also continously change the angle, for the same reason. But then I'm getting into the industrial art, rather than the home hobby.