This is taken from this website  http://en.wikipedia.org/wiki/Smooth_Collie
        Funny how they have a clearer understanding than the 
CCA!!!!!  Tho they kinda screw up counting the colors.

Color

Smooth Collies come in four colours: 1)sable (Lassie's colour; can be 
light gold to deep mahogany), 2) tricolor (black, with tan and white 
markings), and 3) blue merle (silvery gray marbled with black, and tan 
markings), all marked with white areas on the chest, neck, feet/legs, 
and tail tip. An additional color is white (these Collies are 
predominantly white, with heads and usually a body spot of sable, tri, 
or blue color). The fourth color is sable merle, which is a light 
stippled version of sable, sometimes (as with blue merle) accompanied 
by blue or merled (parti-colored) eyes. Blue eyes or merled eyes in a 
non-blue merle collie are not disqualifications in the AKC standard 
although they are heavily penalized. There are, however, plenty of 
blue-eyed or merled-eyed sable merle collies who are AKC breed 
champions.