Horses come in a wide range of colors and patterns. While many horses are described as brown, some have white markings that make them look quite different. The difference between a brown and white horse depends on the gene pattern and where the color is located. White marks can range from large snips and blankets to the more common spots scattered throughout the body.
The word skewbald refers to a coat made up of white patches on a non-black base color, such as chestnut or dark bay. Some skewbald horses are solid white, and others have pink skin under the white markings. A skewbald horse with a black mane and tail is often called tricolored. A spotted skewbald has spots of varying sizes on a solid colored background, and may have pink or red skin under the white markings.
A silver dapple is caused by a gene that lightens the pigment of the body hair to a chocolate brown and also lightens the mane and tail to a metallic silver. A spotting gene produces a similar effect, but the pattern is lighter and more pronounced.
Some horses are born with a lethal white gene that affects the skin, as well as internal organs. This pattern is so dangerous that it results in the death of most foals that are born with it. A lethal white horse is very difficult to identify. Most horses that are born white will die in infancy because their internal organs are not developing normally.
Brown is the most common color of horse, but there are many other shades that are considered brown. Chestnut is a rich reddish-brown, and there are various tinges of that color as well. Dark chestnut, roan, and seal brown are other examples of brown. The word roan usually applies to horses that have white and dark points, but there are many other combinations as well.
There are also several types of dappling. A spotting gene causes light rings of grey to be flecked over the body, but it is usually not a true roan pattern.
A snowflake pattern is a white horse with splotches of darker colour on its body that lighten as the horse ages. A frost pattern has larger white spots that appear on the body and legs. The term leopard has the same meaning but is reserved for a white horse with small dark spots of varying sizes.
Other types of roaning include rabicano, sabino, and calico. Sabino has a high concentration of white on the legs and belly that connects with roaning elsewhere on the body. A rabicano has a mealy, splotchy appearance that is not a pure roan, but it is a more serious disease than a sabinos.
A paint horse has a pattern of white and brown spots that can cover a majority of the body. The color is not a breed of horse, but it is used to distinguish horses with large spotted patterns from those that are solid or pinto.