Random black skin?

[Athiena14]

Guys I am so confused right now. So cleaning a poopy bum for the first time in this week old chick, I noticed something strange. It has black skin. I know there are a couple breeds that have it but... I dont have those breeds that I know of.

My current laying hens that I have is a cream legbar, barred rock, rir, cinnamon queen, and ee x buff orpington mix.

Roos are ee x rir mix and an unsure mix. The unsure mix is where I think this gene might have been thrown.

I have 1 silkie mix, but its 3 months old.

Any ideas on what the rooster in pic might be and if it could throw this gene out there.

Btw this baby came from a brown egg

 

[Athiena14]

Double checked, this roo does not have black skin

 

[Uff Da]

Is the Silkie mix a rooster? I've heard of roosters beginning to mate that early.

 

[Athiena14]

Is the Silkie mix a rooster? I've heard of roosters beginning to mate that early.

I was rounding up. It's about 9 weeks old. So far looking like a pullet and staying away from everyone with 3-5 week olds in a brooder