As many horse lovers know, horses come in a variety of colors. There are a few basic coat colors, including bay, chestnut and black, and then there is white. There are a lot of variations within those colors, as well as a number of different types of white markings.
The color of a horse is the result of a combination of genetic factors. These can be very simple or very complex and varied. Some examples of these variations are roan, pinto, and sabino.
Roan horses have white hairs interspersed as a secondary color throughout their bodies, giving the effect of a shimmery appearance. A roan may be red or blue, and the white can also be light or dark.
Chestnut horses have a reddish brown body, often with darker points on the head and lower legs. A chestnut horse can be solid or have a flaxen mane and tail. Some registries do not consider brown to be a base color but it is considered a modification of black by most horse breeders.
Buckskin horses have a golden or yellow coat, but the mane and tail are usually black. Buckskin can be pure or spotted, and the spotted version is called a silver dapple. Silver dapples tend to increase in size as the horse ages, and there is also a roan variation of this color, known as the frost pattern.
Pangare is a modifier not yet officially recognized by most horse registries, but it causes the individual hairs to become lighter as they mature. This is the same effect as sooty, but it is more pronounced and occurs all over the body instead of only on the face and legs. A dappled grulla is a dark horse that has white hairs mixed into its coat.
White horses have either very light roaning or are completely white with no other markings. A minimally expressed sabino gene will produce very light, almost imperceptible roaning while a maximally expressed one produces a completely white coat with splotches of darker color scattered throughout it.
There is also a sabino variant with zebra stripes, known as a zebra dun. This is a more subtle form of sabino with a red dorsal stripe and reddish transverse stripe on the legs and over the withers.
A few horses are born white from birth, but they are very rare and must have the dominant W gene in order to be true white. These horses have pink skin and brown eyes.
A few horses are born with a spot pattern that looks very much like a roan, but is actually a form of white called a sanddollar dapple. It is a very light pattern and the spots do not grow in size as the horse ages, but they do not disappear altogether as they do with a sabino. A full-coverage sanddollar dapple is more rare and looks like this horse. The sanddollar pattern is also seen in some pinto horses.