My oldest yorkie Bentley is also a lighter blonde color and his hair is just now starting to turn the steel blue color (he's 16 months old) and he's been accused of being a silkie or not a yorkie at all. He is also akc and while I'm sure he's probably just pet quality I still paid a thousand dollars for him. I have calanders, magaz ines, and just about every yorkie book there is to buy, and I see lots of pictures in these of the "lighter" colored yorkies!
It is my opinion that most vets and onlookers too are not that knowledgable on the breed! Bentely knows he's a yorkie and I know he's a yorkie so I don't really care what anyone else thinks
Just because a vet has a degree on the wall does NOT make him/her a Yorkie expert!
I totally agree with Yorkierose!