A strikethrough -- I hadn't thought about that, thank you.
I should have mentioned with respect to the first photo that it is definitely some kind of gouge, not residue. It's as if someone took a woodworking awl, dug into the tail feathers and chipped a flake off the top layer of the surface.
Yeah, the third photo isn't great. I've included two more below -- more close up, though the quality isn't much better. For what it's worth, the surface of the gouge (or whatever it is) is very rough, like what you'd expect to see if you cut a chunk off a rock.



I should have mentioned with respect to the first photo that it is definitely some kind of gouge, not residue. It's as if someone took a woodworking awl, dug into the tail feathers and chipped a flake off the top layer of the surface.
Yeah, the third photo isn't great. I've included two more below -- more close up, though the quality isn't much better. For what it's worth, the surface of the gouge (or whatever it is) is very rough, like what you'd expect to see if you cut a chunk off a rock.


