The flatly-struck breast is common on 1921-dated Morgans which were hubbed based on a modified and re-engraved 1878 "2nd Reverse of 1878" 7 tailfeather/parallel arrow feather reverse die.
In 1879 (for most issues) the breast feathers were modified to be sharper and more easily discernible, a change which lasted through 1904. A much smaller number of S and CC branch-mint Morgans were made using the "old" flat-breasted reverse design through 1880, to the best of my remembrance.
The other lines you are seeing are known as "die cracks" and occur when the dies used to strike the coins develop stress fractures for a variety of reasons such as improper hardening, impurities, high strike pressure, age, and wear over time. The cracks show up as RAISED lines on the surface of the coin, as opposed to post-strike damage/scratches and gouges which will be LOWER than the surface of the coin.
I would need better pictures (in natural light, no flash) to tell you more about the 21-S.
The rim damage above M in AMERICA in one of the coins you listed is post-strike damage. In between the E and R on the same coin, you can see a die chip in line with the crack, where a small piece of the die actually chipped off.
- EAC - TNA - SSDC
Specializing in 1932-1964 Washington quarters
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