What Would Cause This?

ok I'm far from an expert but my opinion is that it was probably grease or something on the die when it was struck. I would get a second opinion though. there are many people on here that are far more knowledgeable than I.

John1

In my opinion, it was Struck Through Grease. The boundary between the well-struck areas and unstruck areas is too abrupt for a low-pressure strike. The rest of the design and the design rim are too well-struck for this to be a low-pressure strike. In many cases, grease tends to flow toward the areas of lowest effective striking pressure, which in this case would be the area opposite Lincoln's head and his coat. That's roughly the pattern we see here. I'm not sure I've ever seen a "weakly hubbed" die. You wouldn't expect a weakly hubbed die to show absence of the design so far into the coin, since this is near the apex of the cone-shaped face of the unfinished working die, where effective hubbing pressure is quite high.

Maybe 50 cents.

Not all grease strikes show a texture. The coarseness of the gunk filling the die is quite variable. As for thinned peripheral lettering, I think a more prosaic explanation would be intentional die abrasion.