A: This is going to depend on whether you're actually removing a scratch or just polishing what seems to be a very dull area. If you are removing a scratch, keep in mind the process is going to work a lot like sanding and finishing. It will require starting with a point that can reduce the appearance of the scratch. Then work into finer accessories from there. You may have to try a couple of items. For example, you may want to try a diamond wheel point. This will tend to create a more etched appearance on the glass. If removing a larger scratch, start with that. Then move to finer items like emery-impregnated points, a felt polishing point with polishing compound on it and finally rubber polishing points.
A: This will depend on the stone. It may be very difficult to achieve a high polish on some stones. Semi-precious stones are going to polish in a fashion similar to glass, where the scratches or flaws are reduced in size and then polishing compound helps draw out the shine. Keep in mind that the polishing compound we offer is not the only compound available. Polishing compounds will also have a higher grit rating. You may have to move up the scale to get the appearance you desire.
A: Brass is one of the softer metals, and should only be polished with soft materials like the cloth polishing wheel. Care should be given to start with polishing items that will not create more scratching. Start with polishing compound and then proceed from there. If you are removing a scratch, keep the polishing area small, or you could find yourself polishing forever. Keep in mind that if you are polishing an item that is only brass plated, you could easily remove the plating with the polishing compound and tool. Stainless steel is a little different. It's tougher than brass. You could also find that polishing compound could get caught in the porous finish of stainless, and it would be difficult to polish out. If you are not achieving the look you need on stainless, consider a polishing compound that has higher grit.
A: Try cleaning with a bristle brush. The bristle brush will get in and around many areas that might otherwise be tough to get at. The bristle brush isn't aggressive enough to scratch or damage the gemstone.
A: It is a solid compound. There is a fallacy that exists about polishing compounds and waxes. It is the concept that "more is better." That isn't really true. When using waxes and polishes, it is often more effective to use a more conservative amount and then repeat rather than have to remove an excess. If you apply too much polishing compound to the material being polished, the excess polish coupled with the speed of the tool will create swirl marks on the surface being polished. Removing those will require several clean felt or cloth polishing wheels.