I have a couple of light scratches on the back of my iPhone 4. I babied my iPhone but I have now realised the scratches are from my wedding ring when I hold it. I am now using a case but does anyone have any ideas if it is possible to remove scratches from the glass on the back? I have heard toothpaste might do the trick. The scratches are very light and I cannot feel them with my finger nail. Does the back glass have a special coating or anything that could be ruined?