Help Window over the rear facing camera is made from.......

[jirams]

......... from plastic. I had a slight scratch on it and managed to polish it out using 1 micron diamond polishing paste on a Q-tip followed by 0.25 micron paste. The scratch is gone too easily and the remaining condition of the window surface is how plastic rather than glass looks after using this paste.

 

[Gearu]

Yeah.
Only solution is to get a gorilla glass screen from someone's broken phone and use something to cut it to shape, polish it on both sides then glue that on.