1970 D Error Before The Strike?

I would agree that the two errors are unrelated. The obverse definitely has some sort of peripheral die damage, but I hesitate to characterize it as either collar clash or a die attrition error. I suppose it could be damage from colliding with the top of the collar (a form of collar clash), but the thin, arcing ridges are not entirely consistent with that scenario.

It looks like the poorly-struck areas could be either a grease strike or a slightly weak strike. In either case, it looks like the poor strike has revealed a slightly cracked surface. If so, we're looking at a planchet error. These superficial cracks might have been smoothed-out by the strike in other areas.

I don't understand your observations and analysis. The weakness on the reverse lies opposite the bust of Lincoln in vertical space. That's what you'd expect of a slightly weak strike or a grease strike that produces a "greasy ghost" image. The high points of Lincoln's coat are also poorly struck, which cause me to lean more toward the weak strike diagnosis.

I actually thought this would be an easy call for an expert as only so many things could do this. But seems like it isn't so straightforward!

I debated about using the word "grooves" because what are the marks, the grooves or the ridges? I don't know, but since the grooves are down into the field on the left side I went with that.

Here are some comparative photos to show what is raised and what is grooved. The yellow lines are incised and between them is raised. On the right above the you is a set of four very small stair steps, but they are very small are darn hard to tell exactly which way what goes in the lighting. But they start at the field and end at the top of the rim.

Thank you Mike. I have been doing what research I can on this and now with your comment I think I can label this one as collar clash and be pretty confident with that. IT is a new error type for my collection.