This came out of a 1973 Mint Set and I noticed the great strike with the feather skirts on the legs of this eagle. How would you grade this Washington Quater?
MS-65 because of small marks on the obverse and the black spot. NGC would probably grade it higher. They are not as tough on modern coins as PCGS which is why PCGS is “the grading service” for modern U.S. coins.
Maybe, but it could also be in the metal. In that case you would have to dig it out which will leave a distracting hole in the surface and maybe a “details” grade.
I think, in this case, it is just a little distracting greese on the surface of the coin. It came from a mint set.