Micro Coin Characteristics we can find on our coins.
Insider2
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Striations that were on the original planchet that were not obliterated by the strike. When they are similar to these, they probably came from worn rollers as the strip was being made. Our modern planchets are made outside the mint so if any member knows differently feel free to educate us.
The parallel lines are into the coin's surface. We can tell these are not scratches (PMD) to the coin because of the microscopic original surface inside the lines.
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I though the striking process always obliterated everything on the planchet.
Sure does look like a feeder problem, either in the planchet or finishing unit.
Posting another per same.
If true in line production guess, were these dirty rollers?
Jut putting it out there, if I may?
Come on Bryce, I believe you are trolling
to be funny. Now please edit your post as it will lead many astray! 
This is a completely different characteristic on a coin. Can you guess what it is and point out the differences?
Well, I think I'll leave the post....... people who go outside by themselves and tie their own shoes should be able to interpret a
without getting too suckered in.
To be a good sport, here's another example with the striations evident on both sides. They seem to be common on modern cents, and I've seen them on Ikes a few times. Evidently they don't bother our host much as they gave this coin a 69 grade:
I was able to find these old photos of an Ike I used to own:
You would be very surprised at how little many dealers and collectors who tie their shoes and dress themselves very well know about coins! Slabs have leveled the numismatic playing field for those folks.
Still studying and learning,
Could this be caused by improper alloy mix?
I have had a few coins look like this
Here's another common way that surface features on a planchet can end up on a final coin. The 1921 Peace dollar is famous for not being completely struck up in the centers. Compared to most coins (and perhaps because De Francisci knew more about sculpture than coinage), the original design was done in pronounced high-relief. The highest parts of the design are produced by the deepest parts of the dies.
In late 1921 the workers at the Philly mint discovered that the only way to fully strike the coin was to exert a much greater than usual striking pressure. As a result, the dies were failing very quickly. In order to get a few coins minted before the end of the year, they reduced the striking pressure and settled for an incompletely struck coin. Modifications to the coin's relief were made for the 1922 and subsequent issues.
Consider this coin:
The highest part of the portrait relief is the hair detail above Liberty's ear. As you can see, the coin is relatively flat in the area contained within the red circle below. Most 1921 Peace dollars are even more poorly struck than this example, but this is the weakest strike that I have a photo of. The planchet in this particular area never touched the dies and remains as it was before it went into the press. These areas will not demonstrate normal mint luster. Any irregularity to the planchet in this region will persist on the final coin.
The TPGs will often overlook a bit of roughness in these unstruck areas. To the casual observer, it may appear to be a central patch of hairlines, a bad central abrasion, or high-point rub, but in reality it's only an incompletely struck coin.
A careful look at the coin will also reveal a few regular contact marks (or hits, or abrasions) in the green circle and die polish lines in the blue oval.
Yes.
I hope this gets "Best of Posts."