What can be done to get rid of a stain on a Corion sink?

try a scrub powder with oxalic acid, such as Bar Keepers Friend or Zud. If that isn't enough, use bleach in water

I checked and you can soak a Corian sink with bleach for as long as 16 hours. Maybe you just haven't given it enough time. Also, you can Google "Corian sink care" for the manufacturer's suggestions.

Stains have always been easy to get out with cold, yes, cold water and fresh cream of tartar. Make a paste of the powder and let it sit over night, making sure it stays wet and doesn't dry out.You can stick some wax paper or plastic wrap to it to keep it wet. In the morning, it should scour off easily with one of those "for Corian" scrubbie things.. good luck!

Try making a paste with cream of tartar and lemon and allow to sit on overnight.Do not use bleach as it will not take the stain out it will do more damage.

Believe it or not, you can scrub it with ajax or comet--it will not hurt the corian! Sometimes I do this all over just to get extra clean--takes a couple of rinses but turns out very nicely.

Is it a stain or did it get burned because someone set a hot pot in it and scorched it?

I think I remember that you can lightly sand stains in Corian to remove them. Use a very fine grit sandpaper.