How to Sand Scratches on Rock

"Hi, I'm Jason with expertvillage.com. We're making the rock charm for a necklace today. We've done all the cutting. We've done the edges. We've drilled the holes. And we marked the black marker all the deep scratches. So now with the same cutting bit that you had on the dremel, we just want to go over those. You don't want to actually dig right into it because then the rest of you will have to mark the whole rock all over again. So just go over it, and when the black lines disappear, you know you're gone with that spot. So if you want you can go and move around side to side or you can do one spot all at once. I like to do one spot all at once and move on. Now the marker will wash away with the moisture from the water on the surface but it will still remain in the cracks. So you don't have to worry about messing it up by getting it wet. So we'll grind these scratches out now. Now we'll look over... rinse it off and dry it and look over it and make sure there are no marker marks left inside the scratches."