Instructions from Dupont (Corian manufacturer)
I've polished parts of mine 2-3 times in the past 8 years. Our Corian tabletop gets a lot of scratches, as does the primary galley work area. Other places, not so bad and I've just given them one light polishing.
There are polishing creams available in stores that work ok to bring up a new shine, but aren't strong enough to remove any actual scratches.
2004 American Tradition; 2014 Buick LaCRosse
Homebase in the Ocala Nat'l Forest near Ocala, FL