Hi,
I believe white with a black centre is just "badger", and I think ginger with a black centre and black tips is called a "Greenwell's" because it was used for Greenwell's Glory. I've seen some photos of black tipped badger-type feathers, but I've never come across any. A shame as I would think these would make a great hackle. Perhaps, like blue dun, they are quite hard to produce? I'm sure Denny would know.
- Jeff