Silver... buy 3M light rubbing compound!! it works great on scratches in the bumper. Dont watersand unless you have to. as a rule of thumb the higher the grit of watersand paper the better the finish as long as you keep it wet! the apply some finishing glaze. Try the 3M stuff first I got a bottle from PepBoys for $5.99 it works great!
Yes! The 3M rubbing compound rocks! My wife's old eclipse "accidentally" grazed the side of my house (my fault). It left hella bunch of scratches. Used the rubbing compound. Couldn't even see my boo boo. She never knew!