Thanks, gents, I felt truly honored to be asked!
@Alberto: the wire is silver wire, the thinnest non-tarnishing wire I could find. As for the hackle: I normally use Whiting rooster saddle, dyed Coachman brown for this pattern but ran out of the right size of that color. So I used Grizzly dyed dark brown instead - so one color. The pic has a reddish cast over it though.