NO. Down and Feather are like human hair and it may contain a very small amount of darker down or feather. There are no official standards that explicitly describe the tolerance for dark material in a white feather or down. In the USA a general rule for textile tolerance of 5% is sometimes used. In Europe a tradition of 2% allowance is sometime used.
Our quality internal standard for white is less than 3% and super white is less than 1%
in dark points.