Quote:
Why can't the debris be soft enough to just leave a "mark" and not press into the planchet?
Because it
did, in fact, leave marks. Just marks formed by what could only have been something close to a "point source," with only a
very small width. Something
sharp. Only a "periphery" is outlined, where an artifact like a dropped letter would assuredly have X, Y and Z dimensions and should be deepest in the center. Or at least clearly deeper in one place than the other.