OO> I've been polishing my 8" mirror with CeO and it looks done to me. OO> I've only been polishing for 5 - 6 hours, so I'm skeptical about OO> my Mitch,
It is possible that you actually are finished polishing. There may be other better ways to check the finish but the one that I use seems to be fairly reliable.
Lay your mirror face up on a dark background. Hold a flashlight in one hand at about arms length and at a 45^ angle to the surface of the mirror. Now take a magnifying glass (reading glass) in the other hand and focus the beam of the flashlight to a small spot on the surface of the mirror. If completely polished, you should barely be able to see the spot on the surface...the light just goes through the mirror. If it is not polished, you will see the spot of light on the surface.
Pay particular attention to the intensity of the spot toward the edges. This is where most folks fail to complete polishing.
Good luck!
Mike
* RM 1.3 * Curiosity didn't kill the cat. I got 'im with the mower!