A natural black nosed dace is very distinctive and they're only found in the cleanest water.
In Art Flick's "Streamside Guide" (c.1947) the recipe is
Body---Best quality medium silver tinsel
Tag----red yarn, very short
Hair---- natural polar bear , black bear or black hair from skunk tail, and brown bucktail
Hook--- No. 4,6,8, or 10
He goes on to say that white bucktail can be substituted for the polar bear, but the polar bear hair is preferred because it has better action.
I caught some nice landlocked salmon and large brook trout on black nosed dace this season.... all tied Clouser style