Dark Grey Dun, a hallmark of Catskill color palettes, ranges from the darkest medium grey dun to an almost black hue. Generally, this color presents an overall grey tone, but upon closer inspection, subtle dark tans and browns are revealed. Another distinguishing characteristic, particularly prized in Catskill dry fly patterns, is a dark bronze flecking overlaying a darker grey dun base color. This shade transitions into medium grey dun, brown grey dun, dark brown dun, and black, demonstrating the subtle gradations inherent in natural materials. The captivating depth of dark grey dun is often replicated through dyeing, a practice common in the pursuit of achieving those prized Catskill hues. As with the dyed medium grey dun, discerning between natural and dyed feathers can be challenging, and this difficulty is even more pronounced with the dark grey dun, a color so integral to the Catskill fly tying tradition.