Gary, I tried the newspaper trick, it was a no-go for me. This was on a new piece of glass in a LeisureLine Pioneer burning only about a 1.5" fire, just above an idle.
Mark, I have some car cleaner/polish, I'll give it a try, I assume only on a cool/cold glass surface??
I may try rubbing compound too....
It's tough stuff! 150 grit sandpaper, wet/dry type??
PS: elkvu, please turn off the CAPS LOCK on your keyboard. Typing in all caps is considered YELLING. Hard on the eyes too.