It's purely a particular artistic style. Because the word "of" is considered to be a minor preposition it is often not capitalized in titles and headlines. Sculptors and inscribers sometimes morph that idea into the peculiar-looking combination of a small "o" and large "F". The practice was more common in the early 20th century, along with using the Roman alphabet that substituted the letter V for U*. See for example the lettering on a $2.50 Indian Head gold piece and on the famous St. Gaudens $20 coin.
(*) There's a very long thread where several of us try to convince posters that "In God We Trvst" is NOT a typographical error!!
25 cents.
The date is 1776-1976 and it's only a quarter.
Yes. There were US quarter dollars struck in 1975 but all of them carried the date 1776-1976. Likewise, all 1976 quarter dollars also carried the 1776-1976 date. There is no way to identify the coins struck in 1975 from those struck in 1976.
Only face value unless in mint packaging.
All US Quarters made in 1975 & 1976 have the dual date 1776-1976 so if the coin has a date of 1975 it's not a US coin.
All bicentennial coins were minted in the years 1975 and '76.
Not a lot, and most people ask too much.
Please check your quarter again and post a new, separate question. The first US quarters were minted in 1796. If you have a dual-dated 1776-1976 quarter it's one of the billions minted for the US Bicentennial, and is worth only face value.
It may have been plated with gold but it adds nothing to the value of the coin.
It is worth face value unless it is still in the original mint package.
It's the Denver mint mark, indicating where it was made. And does not add to the value it's just a quarter
No US quarters are dated 1975, all have the dual date 1776-1976