LOL She is going to be typing a long time!
I think destiny mentioned earlier than other breeds were introduced along the way to make different varieties of Silkies. In the beginning, there was just the whites. So, some colors (black and white usually) are silver based colors. Colors like buff and reds are gold based. So, depending on what the genetic soup is that makes up your white chickens, you can have gold that comes as a bird ages, as is the case with one of mine that I know, or exposure to sun. Eating corn, especially a diet higher in corn or feeding it as an extra can help give chickens more yellow legs and beaks, but this is the first I have heard it effects feathering color.
The gold base is what gives the Black Sex Links their orange or red or yellow coloration around the neck. The gold base color is being expressed like a leakage. That is why in some crosses, you may have a barred bird, like Ralphies crosses, but then they get gold leakage in the shoulders or hackles or saddle feathers. It is kind of like natural highlights. Sun will intensify that and make it look more yellow. It can and does do that to a lot of white chickens though, which is why show breeders won't just turn their white birds outside all the time. My New Hampshires, if out all Spring and Summer, their feathers go from golden bay to yellow and look terrible.
There is so much that goes into color genetics, it can get really crazy. I know there are threads on here that are just about color genetics, but be careful, because a little knowledge is a dangerous thing, which is why I always try to remind people, don't just listen to what I say, research further.