Emery paper sanding on glass takes forever, and may not work well. It usually leaves a cloudy surface that can be polished with jeweler's rouge if you have much time and patience. If you are going to try it , nail files that are made for acrylic fingernails are an economical way to get 2 grades of emery paper without having to buy 2 packs of emery paper at the DIY store. Get the file that has a charcoal grey side that actually feels smooth to the touch. It's the same as the finest grade of emery paper. Get one at a $1 store.
Because the file has a foam center, it will be easy to use and can be cut to a desired shape. Use the rougher side first, then the smooth side to finish. Using a small amount of water or mineral oil as you file the glass will help get a smoother finished surface.
If money doesn't make that much difference, you can buy a crystal file called "Crystal Saver" for about $39 .A fast search will show where to get it online. It's a slow going process, but the end result is worth it.
annette, November 2008