When buying a Border Collie, you must pay attention to their eyes. Even dogs that look very similar may not be pure Border Collies.

Dogs with the black genotype should have black and black-based eyes (for example: black and white, multi-toned black, black and red). Dogs with the chocolate genotype should have a dark auburn nose and light brown or amber eyes. Dogs with the blue genotype should have a (similar to slate color) dark bluish-gray nose and lighter colored eyes. Dogs with a red genotype can have both a chocolate genotype and a black genotype. Therefore, some dogs with the red gene will have dark auburn noses and light eyes, while other dogs with the red gene will have black noses and dark hazel/brown eyes.

Some of the standard statements about eye color are often misleading. Of course, except for the merle, which will have blue eyes, the eyes of this breed of dog should be various shades of brown (this does not mean whether this applies to one or both eyes) There is no indication whether this rule applies to one eye or both eyes). However, since colors have a range of levels. Therefore, the statement that "dark eyes are best" applies to any dog ​​is extremely wrong. A Border Collie that is not black as the base color may have light-colored eyes and will not be disparaged in any way because of this.

But the most important thing for the merle dog is the expression of the eyes: "docile, alert, vigilant, and intelligent." When your dog looks at you, you should see trust, loyalty, intelligence, and interest, not just eye color. That is to say, strong or empty expressions can be seen in eyes of any color. (Border collies without black genes have light-colored eyes, and they will not be disparaged for this) Explanation on merle color (marble) dogs: Unfortunately, because there is no merle color in the (Border Collie) standard, The term "marble" dog is used without sufficient explanation or careful consideration, resulting in the standard being contradictory in certain places. Some standards allow merle dogs to have either all blue eyes or one brown and one blue eye, and their coat color can be either solid light or speckled. Some standards allow dogs to have pink spots on their noses. Most standards provide detailed descriptions of coat color and pattern. As there are no merle colored dogs in New South Wales, this document (Border Collie Standard) does not currently provide any explanation of merle colored dogs.