I see no one has replied yet. I wish I could give you a educated answer, however I also have a silkie mix that has some of that splotchy black skin. It's not as noticeable on my silkie mix though. In my case it seems to be under the feathers on its body. The only way I know it's even there is because the chick is a white silkie mix. I just thought it was pigmentation from both parents. I am under the impression that pure bred silkies will have black skin, and I have pure silkie who do. Then any mixes that hatch seem to have either white skin, or splotchy black.
