[rrosenberry]

have you looked in Yorkie books I have a few that have great photos in them, or do a search on the net and pictures should show the difference in color.

I was looking to try to post a link,, still looking found this though~
Color

Puppies are born black and tan and are normally darker in body color, showing an intermingling of black hair in the tan until they are mature. The mature coat color occurs gradually, therefore puppies should not be faulted for lack of color change until they are two years old. The colors in adult dogs are:
BLUE - a dark steel-blue.

TAN - All tan hairs are darker at the roots than in the middle, shading to a still lighter tan at the tips.

On the body, the dark steel-blue extends over the body, from the back of the neck to the root of the tail. The headfall is a rich golden tan, deeper in color at the sides of the head, at the ear roots and on the muzzle, with the ears being a deep rich tan. The tan color should not extend down the back of the neck.

The hair on the chest and legs is, a bright, rich tan, not extending above the elbow on the forelegs or above the stifle on the hind legs.

Faults: In adult dogs, fawn or bronze hairs mingling with silver-blue color. Sooty or black hair intermingled with the tan.

Disqualifications: Any change in coat color by artificial means. Albinism.