IMO the white is a gamble that probably won't pay off. Just because you can't tell anything about her. She may be silver but you won't know until you breed her. The other problem is you don't know what else she is.
For gold sex links you need chicks that hatch with enough gold/silver areas to see which they are. If she's black underneath the chicks will hatch mostly black so there won't be any gold/silver showing to sex them by.
The white silkie will have the same issues. He should be recessive white so could work crossing him to cuckoo.
He can be used with any of them to make skin color sex links. Cross a silkie rooster with your yellow skin cochins and pullet chicks will have dark skin like the silkie and cockerel chicks will have yellow like the Cochin.
For gold sex links you need chicks that hatch with enough gold/silver areas to see which they are. If she's black underneath the chicks will hatch mostly black so there won't be any gold/silver showing to sex them by.
The white silkie will have the same issues. He should be recessive white so could work crossing him to cuckoo.
He can be used with any of them to make skin color sex links. Cross a silkie rooster with your yellow skin cochins and pullet chicks will have dark skin like the silkie and cockerel chicks will have yellow like the Cochin.
