Wild-type blacks to show some brownish tinges. Dusky blacks have most or all of their brownish tinges removed.
Your birds have some white feathers on the heads -- are they under 2 years old? If so, I'd suspect they have the white-head gene, which takes a couple of molts to show completely.
Your birds have some white feathers on the heads -- are they under 2 years old? If so, I'd suspect they have the white-head gene, which takes a couple of molts to show completely.
