On the color, if I am understanding it correctly, it is like a recessive that has carried through the generations seen or not depending on the combination of the parents since the founding dogs.
Now the AKC (American Kennel Club, the premier dog registry) does not have the Gold or Blond as a showable color at this moment (standards are always changing), however in my limited search of pedigrees, I have come across a Champion Yorkshire Terrier registered with the AKC that is listed as GOLD as it's color, CH.Pretorius' Dandy Sensation.
So, if you like a color and it is not a current acceptable color, I feel that life is too short to worry about it as it does not harm the dog so enjoy and if you wish to breed, bred for the betterment of the breed, include such things like temperaments and health as well as conformation as very important aspects.

