This is a natural color as far as I can tell.
A single feather from the skin. Strip the short fibers at the base of the feather and use the longer fibers for the wing.
Pull a few fiber from the stem.
Gather the fibers and pinch off the tips.
To get them to look like this.
Tied in bundle.
Make sure you do not leave a big space behind the eye. Otherwise, you will have a long front portion to your flies. I like a short, nice taper in front of the wing.
I use a half of a double sided razor blade for a very close cut. Make sure you break the razor in half because it's very easy to get cut as I found out.
This makes a very close cut that scissors cannot make.
See, what did I tell you? A clean, close shave.
Not the same fly, but the finished fly. Lots of movement in the wing for below the surface use.