F in of looks funny, as does the E on United and the undwrsiun of the word quarter. Probably nothing, I have an appt with an optometrist tomorrow.
Could be small Die Chips and a bit of Circulation wear. Honestly anything that needs that much magnification is not worth it.
The F is normal, that was how it was designed. As far as QUARTER goes I see some die wear but the entire coin appears pitted. I can't tell if it really is, or if I'm just seeing pixilation from over-enlarged low resolution images. I'm also not sure what you are saying is there because "undwrsiun" doesn't mean anything to me.