The only way to remove scratches from glass that has to stand up to heat is to polish them out using successively finer grades of polishing compounds. Simply do a web search for 'glass scratch removal' and you will find lots of info and kits. I found on one search page three kits under $35 each.

Point it out to him. Let him know, if he wants to get paid, he needs to resolve what he said he could.

HomeSealed, Cerium Oxide is widely used for grinding and polishing glass and since it does fall into the rare earth category, it is very possible (likely) that you are using it as a buffing compound. The very finest grade of cerium is reserved for applications such as grinding and polishing high end telescope lenses and it is eye-openingly expensive.

raee, I'll share with you what has worked for me for placement of "the line". After the failures previously mentioned, I decided I needed to be more proactive to "help". When trying again at a new place, after the optician made the measurement and started to write it down, I asked where the line was. The response was "I put it at the point most people find comfortable". "Will I find it suitable for me?" "Yes, you probably will" "Please draw a line on the lens (the plain lens put into frames before sold) so I can see where it is" "You don't trust me?" "I neither trust you nor distrust you, I want to see where it is". Line is drawn, I put on frames "It's too high" "You don't want it much lower" "Please put it lower" New line is drawn "It's still too high" "It can't be much lower, you need enough lens at the bottom for the progressive pattern" "Are you saying it CAN'T be lower at all, or it can't be much lower?" "It can't be much lower" "Fine. Put it lower and let me look" (what I was doing was checking out the field of view for distance viewing) "Okay, that's fine" "I think it's too low" "It's fine. Please use that" It was perfect. I've done it the same way ever since (but haven't gotten new lenses in the last Covid year). I start by having the optician measure the distance down from my cornea to where the line is on my existing glasses. Here's the thing. What works best for me when using progressives, and changing to close-up viewing, is to keep my chin high and look down with my eyes. If you turn your head down, you're then using the distance corrected upper part of the lens and reading will be difficult. . Good luck to all.