Dexters come in several colors, although they are always solid colored; never spotted. Many have white on their udder.  The three basic colors are Black, Dun, and Red. However, animals that are black at birth can sun fade and look quite red, especially their first summer.  They will go back to black when their hair sheds out and should not be considered Red or Dun.  Dun comes in shades of blond, cocoa brown, strawberry blond, and mahogany. Duns always have a tannish brown nose and brown "eyeliner," although their eyes are typically lighter in color than the eyes of other Dexters. 

Red comes in shades from bright carrot red to very deep red.  It is usually the darker Duns that cause confusion, since they start to look like the darkest Reds. There are two types of Red:  Reds with pink noses, and Reds with black noses. The pink nosed Reds have pink "eyeliner" (which helps to tell them from the duns). The pink nosed Reds are associated with the "e" genotype, or "true" red and a lighter coat color. The black nosed Reds are associated with the E+ genotype or "wild-type" red and a darker coat color. However, since other genes are involved with the color of the nose/eyeliner, and the darkness of the coat, there are exceptions, and you cannot be sure of the animal's red genotype without a test. Here are some examples of color variations and nose/eyeliner color.  

Red with Pink Nose

Red with Black Nose

At this point there is still much confusion over Duns and Reds, and up to a few years ago all non-black Dexters were registered as Red, and then Red/Dun. However, it was clear that more than one gene was involved.  For example, breeders with Dun animals could breed Dun bulls to Dun cows and get nothing but Dun calves.  Breeders with Red animals could bred Red bulls to Red cows and get nothing but Red calves. But, when the breeders traded stock and bred Red to Dun, the first generation of calves usually came out Black! When those Black calves were bred together, Black, Red and Dun animals were produced.

We now know that the genes responsible for Red and Dun are not located anywhere near each other, and the two colors are genetically quite different. In order to get this straightened out, the registry requires testing of all Red animals to make sure they are not Dun. It was easier to single out the Red animals because the genetic test for both types of Red is more widely available and most Red animals in the U.S. descend from handful of popular A.I. bulls: Marnel's Black Magic, Lucifer of Knotting, Saturn of Knotting, Saltaire Platinum, and Cornahir Outlaw.

The gene responsible for Dun coloration in Dexters was discovered in 2002 and has not been found in any other breed. The fact that the market for the test is limited to Dexters, (a rare breed) and Dun Dexters (rarer yet) has limited the marketability of the test, and thus the availability.  Of course, you can look at the Dexter Dun coloration as possibly more special, since it is unique to the breed.

It is quite possible that the reason Red and Dun are rare today is because these colors were selected AGAINST in the early stages of the breed.  When all three colors are represented, new buyers (who may not be aware of the scarcity of Red and Dun) often select Black as their preference. Ultimately, color preference is a personal choice. It is important that an animal not be selected for color only, as this trait is not important to the health and function of the animal.