In a nut shell, two main pigments are responsible for horse coat colours are eumelanin (black) and pheomelanin (red/yellow). The chestnut or red coat occurs due to the absence of extension gene (‘e’) while black is produced by the presence of extension gene (‘E’).
Black, gray, bay, and chestnut are the fundamental coat colours, but they are not the only coat colours. There are many more coat colours and patterns, including those created by the interaction of these basic colours with various dilution genes and modifiers.
The mixing or absence of pigments, as well as the presence of various genetic factors, can create a wide and diverse range of coat colours. For example, the interaction of black and various dilution genes can produce coat colours like buckskin, dun, and grullo, among others.
Paint and Appaloosa: Paint and Appaloosa are not coat colours but rather horse breeds known for their distinctive coat patterns. Paint horses typically have large, irregular patches of white and another colour (tobiano or overo patterns), while Appaloosas are known for their unique spots and patterns, which can vary widely.
While a few horses may change colour as they age, most horses retain the same coat colour through their whole life. However, the underlying skin colour may change due to a disease.
What are the five basic horse coat colours?
Horses exhibit a variety of coat colours, but they can be categorised into five fundamental hues:
- Bay: Bay horses have a reddish-brown body with black points, which include the mane, tail, and lower legs. This colour is one of the most common in the equine world.
- Chestnut/Sorrel: Chestnut or sorrel horses have a reddish-brown body with a mane and tail of a similar or slightly lighter shade. They have no black points, making them distinct from bay horses.
- Black: Black horses have solid black coats, manes, and tails. This colour is striking in its simplicity and is admired for its elegance.
- Grey: Grey is an interesting colour because horses born with any coat colour can eventually turn grey as they age. These horses progressively lighten with time, and their final coat colour can vary from light grey to white.
- Palomino: Palomino horses have a golden coat with a white or pale mane and tail. They are known for their striking beauty and are often associated with a touch of glamour.
Horses come in a wide variety of coat colours, and these colours can be further modified by various patterns and markings.
Here is a comprehensive list of horse coat colours, along with some common patterns and markings:
Bay horse colour
Bay is one of the most common coat colours in many horse breeds.
Bay is a hair coat colour of horses, characterised by a reddish-brown or brown body colour with a black point colouration on the mane, tail, ear edges, and lower legs.
The black areas of a bay horse’s hair coat are called “black points”, and without them, a horse is not a bay horse. Black points may sometimes be covered by white markings, however such markings do not alter a horse’s classification as “bay”.
Blood bay horses have a black base (as all bays do) which is brought on by the Agouti gene. The job of the Agouti gene is to decipher whether or not the horse with a black base will be brown or fully black. A dominant Agouti gene means the black will be limited to the points (mane, tail, ears) and the body will most likely be a shade of brown. If the Agouti gene is recessive, the horse will be completely black.
Essentially, this means that when a black horse has a dominant Agouti gene, that horse’s appearance is what we call bay.
Chestnut/Sorrel horse colour
Reddish-brown to dark red coat with a mane and tail of the same colour.
Chestnut horses can be pale reddish to dark coffee colour, and all reddish-brown shades in between. Most associations recognise the chestnut colour, but they can’t seem to agree on the same terminology for each shade of Chestnut.
The one thing breed associations can agree on is that a chestnut horse has a reddish-brown coat with no black points. If the horse has any black hairs at the points, they cannot be registered as a chestnut.
Liver chestnuts are darker than the other shades of chestnut. Sometimes, their coats are so dark that they are even mistaken for bays, but the key difference is that their manes and tails are the same shade of brown as the rest of their bodies instead of black.
Flaxen chestnuts have a genetic trait in which the mane and tail of chestnut-coloured horses are noticeably lighter than the body coat colour, often a golden blonde shade. Manes and tails can also be a mixture of darker and lighter hairs. Certain horse breeds such as the Haflinger carry flaxen chestnut colouration as a breed trait.
Black horse colour
A solid black in which the entire hair coat is black. Black is a relatively uncommon coat colour, and it’s common to mistake dark chestnuts or dark bays for black.
True black horses have dark brown eyes, black skin, and wholly black hair coats without any areas of permanently reddish or brownish hair. They may have pink skin beneath any white markings under the areas of white hair, and if such white markings include one or both eyes, the eyes may be blue.
Many black horses “sun bleach” with exposure to the elements and sweat, and therefore their coats may lose some of their rich black character and may even resemble bay or seal brown, though examination of the colour of hair around the eyes, muzzle and genitals often will determine colour. Black horses that do not sun bleach are called “true” blacks.
Some breeds of horses, such as the Friesian horse, Murgese and Ariegeois (or Merens), are almost exclusively black. Black is also common in the Fell pony, Dales pony, Ostfriesen and Alt-Oldenburger, Kladruber, and Groningen.
Grey horse colour
Horses start with any colour and gradually turn grey as they age, eventually becoming mostly white.
A grey horse has a coat colour characterised by progressive depigmentation of the coloured hairs of the coat. Most grey horses have black skin and dark eyes.
Grey horses may be born any base colour, depending on other colour genes present. White hairs begin to appear at or shortly after birth and become progressively more prevalent as the horse ages and white hairs become intermingled with hairs of other colours.
Greying can occur at different rates—very quickly on one horse and very slowly on another. As adults, most gray horses eventually become completely white, though some retain intermixed light and dark hairs.
The stages of greying vary widely. Some horses develop a dappled pattern for a period of time, others resemble a roan with more uniform intermixing of light and dark hairs. As they age, some gray horses, particularly those heterozygous for the grey gene, may develop pigmented speckles in addition to a white coat, a pattern colloquially called a “fleabitten grey”.
An intermediate stage typically seen in young horses in the early stages of turning grey is when white hairs are mixed with the dark birth colour. In horses born black or dark bay, the horse shows mostly black and white hairs intermingled on the body. This dappling is sometimes called “salt and pepper”, “iron grey”, or “steel grey.” This is the most common intermediate form of grey, which can give a silvery look to the coat.
A reddish tinge, called a “rose gray”, describes this intermediate stage for a horse born a chestnut or bright bay. Young horses just starting to grey out are sometimes confused with roans, but a grey continues to lighten with age, while a roan does not. Roaning also causes fewer white hairs on the legs and head, giving the horse the appearance of dark points, which is usually not true of grey.
Palomino horse colour
Palomino consists of a gold coat and white mane and tail. The degree of whiteness can vary from bright white to yellow. The classic palomino is known as the “gold coin” palomino.
Genetically, the palomino colour is created by a single allele of a dilution gene called the cream gene working on a “red” (chestnut) base coat.
Palomino horses have a yellow or gold coat, with a white or light cream mane and tail. The shades of the body coat colour range from cream to a dark gold.
Palomino is created by a genetic mechanism of incomplete dominance, hence it is not considered true-breeding. However, most colour breed registries that record palomino horses were founded before equine coat colour genetics were understood as well as they are today, therefore the standard definition of a palomino is based on the visible coat colour, not heritability nor the underlying presence of the dilution gene. In today’s horse breeding the palomino colour can be created by crossing a chestnut with a cremello.
Due to their distinct colour, palominos stand out in a show ring, and are much sought after as parade horses. They were particularly popular in movies and television during the 1940s and 1950s.
Palomino is a Spanish word meaning juvenile pigeon (the diminutive of paloma, pigeon) and its equine usage refers to the colour of such birds.
What are the dilute horse coat colours?
Dilute coat colours in horses are the result of genetic variations that affect the intensity or concentration of pigments in the horse’s coat. These dilutions can create a range of beautiful and unique colours.
Buckskin horse colour
Buckskin is a colour that resembles certain shades of tanned deerskin. The horse has a tan or gold coloured coat with black points (mane, tail, and lower legs).
Buckskin occurs as a result of the cream dilution gene acting on a bay horse. Therefore, a buckskin has the Extension, or “black base coat” (E) gene, the agouti gene (A) gene (see bay for more on the agouti gene), which restricts the black base coat to the points, and one copy of the cream gene (CCr), which lightens the red/brown colour of the bay coat to a tan/gold.
Dun horse colour
The terms buckskin and dun are often used interchangeably, but there are differences. Buckskin is a yellowish gray with dark points. Dun tends to have more red in the coat.
And what’s the difference between a dun and a bay? The dun gene is a dilution gene that affects both red and black pigments in the coat colour of a horse. The dun gene lightens most of the body while leaving the mane, tail, legs, and primitive markings the shade of the undiluted base coat colour.
A dun horse always has a dark dorsal stripe down the middle of its back, usually has a darker face and legs, and may have transverse striping across the shoulders or horizontal striping on the back of the forelegs.
Body colour depends on the underlying coat colour genetics. A classic “bay dun” is a gray-gold or tan, characterized by a body colour ranging from sandy yellow to reddish brown. Duns with a chestnut base may appear a light tan shade, and those with black base colouration are a smoky gray.
Manes, tails, primitive markings, and other dark areas are usually the shade of the undiluted base coat colour. The dun gene may interact with all other coat colour alleles.
Dun is believed to be the ancestral or wild type colour of horses. Many equines appearing in prehistoric cave paintings are dun, and several closely related species in the genus Equus show dun characteristics.
Cremello and perlino horse colours
The cream gene is responsible for a number of horse coat colours. Horses that have the cream gene in addition to a base coat colour that is chestnut will become palomino if they are heterozygous (having one copy of the cream gene) or cremello, if they are homozygous (having two identical copies of the cream gene).
Horses with a bay base coat and the cream gene will be buckskin or perlino.
Cream horses, even those with blue eyes, are not white horses. Dilution colouring is also not related to any of the white spotting patterns, such as Pinto.
What is the difference between cremello and perlino?
Cremellos are homozygous cream chestnuts, and have a cream coloured body with a cream or white mane and tail (see pictures above). Perlinos are homozygous cream bays, which also have a cream-coloured body but a mane and tail that may be somewhat more reddish in colour than a cremello (see pictures below).
Smoky black colour
Smoky black or just smoky is a hair coat colour of horses which appears dark brown to black in colour. Smoky black is produced by the action of a heterozygous (single copy) cream gene on an underlying black coat colour. This makes the smoky black a member of the cream family of coat colour dilutions, and it’s found in horse populations that have other cream-based colours such as palomino, buckskin, perlino, cremello and smoky cream.
All smoky blacks must have at least one parent with the cream gene, and a smoky black can only be verified through DNA testing or parentage. Smoky black has been mistaken for faded black, dark bay or brown, grullo or even liver chestnut.
Smoky black can sometimes be a bit challenging to identify accurately, especially in certain lighting conditions. Smoky black is a diluted black coat colour, which means it appears lighter than a solid black but is not as light as a gray or a true brown. The main challenge with smoky black is distinguishing it from other similar coat colours, such as dark bay or seal brown. This can be especially tricky in foals that may change colour as they mature.
Smoky cream horse colour
Smoky cream horses have a black base coat but are homozygous for the semi-dominant CCr allele at the C locus (the cream dilution gene). They may be true-breeding for black (homozygous for the dominant extension allele) or not, something which can nowadays be tested for. They do however pass on the cream dilution allele to any and all offspring they may have.
The CCr allele does not occur in some breeds, such as Arabs, Haflingers and many of the draught horses. In these breeds there are therefore no cream horses of any type, nor palominos, smoky blacks or buckskin.
Smoky cream horses have cream coats with pink skin and blue or glass eyes. They often have a very attractive coffee coloured hue, like a latte. Their mane, tails and points may be coffee coloured, yellowish, smoky blue or sooty. If they are not white (due to socks or other white markings) the lower legs may be a darker shade than the body.
Roan horse coat colours
Roan is a coat colour pattern characterised by the intermingling of white hairs with a horse’s base colour. Roan can occur in a variety of base colours, resulting in different roan variations:
- Blue roan horses have a dark, usually black, base colour with interspersed white hairs throughout the coat. The overall effect is a horse that appears bluish-gray.
- Red roan horses have a red or chestnut base colour with interspersed white hairs, giving them a reddish appearance with white flecks.
- Bay roan horses have a brown base colour with white hairs mixed in, resulting in a roan horse with a brownish-red appearance and white flecks.
These roan variations can vary in the degree of roaning. Some roans may have a moderate amount of white hairs, while others may have a heavy concentration of white hairs, almost giving them an appearance of being predominantly white with a few patches of their base colour.
Roan is considered a pattern rather than a separate coat colour, as it affects the appearance of the horse’s existing base coat colour by adding the white hairs. The roan pattern is typically stable throughout a horse’s life and does not change with age, as is the case with gray horses that gradually turn white.
It’s important to note that roan is a separate pattern from other coat colour patterns like Pinto or Appaloosa, which involve distinct patches or spots of colour on a white background. Roan patterns can occur in various horse breeds and are often highly sought after for their unique and attractive appearance.
Pinto and Paint patterns in horses
Pinto and Paint are terms used to describe specific coat patterns in horses, characterised by distinct patches or spots of white and another colour (usually black or brown) on the horse’s body. These patterns are popular in various horse breeds and are often associated with specific breed registries.
Tobiano: white patches with sharp, distinct edges over a base colour.
Tobiano is a spotted colour pattern commonly seen in Pinto horses, produced by a dominant gene. The tobiano gene produces white-haired, pink-skinned patches on a base coat colour.
The colouration is almost always present from birth and does not change throughout the horse’s lifetime, unless the horse also carries the gray gene. It is a dominant gene, so any tobiano horse must have at least one parent who carries the tobiano gene.
Overo: white patches with irregular, scattered edges over a base colour.
Overo refers to several genetically unrelated Pinto colouration patterns of white-over-dark body markings in horses, and is a term used by the American Paint Horse Association to classify a set of Pinto patterns that are not tobiano.
Overo is a Spanish word, originally meaning “like an egg”. The most common usage refers to frame overo, but splashed white and sabino are also considered “overo”.
Splashed white or splash is a horse coat color pattern in the overo group of spotting patterns that produces pink-skinned, white markings. Many splashed whites have very modest markings, while others have the distinctive “dipped in white paint” pattern.
Blue eyes are a hallmark of the pattern, and splash may account for otherwise “solid” blue-eyed horses. Splashed white occurs in a variety of different breeds, from Morgans in North America to Kathiawari horses in India. The splashed white pattern is also associated with congenital deafness, though most splashed whites have normal hearing. Splashed white can be caused by multiple variants across two different genes, for which genetic testing is available.
Tovero: a combination of tobiano and overo patterns.
A horse with both tobiano and overo patterns is called tovero.
The tovero (also known as tobero) coloration is a mix of tobiano and overo colorations in Pinto horses and American Paint Horses. The genetics of Pinto coloration are not always fully understood, and some horses have a combination of patterns that does not fit cleanly in either category.
Sabino: irregular white markings, often with roaning or speckles.
Sabino describes a distinct pattern of white spotting in horses. In general, sabino patterning is visually recognized by roaning or irregular edges of white markings, belly spots, white extending past the eyes or onto the chin, white above the knees or hocks, and “splash” or “lacy” marks anywhere on the body.
Some sabinos have patches of roan patterning on part of the body, especially the barrel and flanks. Some sabinos may have a dark leg or two, but many have four white legs. Sabino patterns may range from slightly bold face or leg white markings—as little as white on the chin or lower lip—to horses that are fully white.
Appaloosa: varying spotted coat patterns.
The Appaloosa is an American horse breed best known for its colourful spotted coat pattern. There is a wide range of body types within the breed, stemming from the influence of multiple breeds of horses throughout its history.
Leopard Appaloosa: Spots on a white background.
Few spot leopard Appaloosa: Few small Appaloosa spots on a white coat.
Blanket or Snowcap Appaloosa: White blanket-like pattern over the hips.
Roan Appaloosa: Roan-like coat with Appaloosa markings.
Dominant white horse colour
A white horse is born predominantly white and stays white throughout its life. A white horse has mostly pink skin under its hair coat, and may have brown, blue, or hazel eyes. “True white” horses, especially those that carry one of the dominant white (W) genes, are rare.
Most horses that are commonly referred to as “white” are actually “grey” horses whose hair coats are completely white. Grey horses may be born of any colour and their hairs gradually turn white as time goes by and take on a white appearance.
Nearly all gray horses have dark skin, except under any white markings present at birth. Skin colour is the most common method for an observer to distinguish between mature white and gray horses.
Other unique horse coat colours
While the world of horses boasts its share of classic hues like bay, chestnut, and black, it also harbours a fascinating realm of unique and striking coat colours. These exceptional coat colours defy conventional norms, often owing their distinctive appearances to specific genetic traits and mutations.
Grullo: Mousy gray with dark dorsal stripe and primitive markings.
A grullo (also known as grulla), like all duns, exhibits a lighter body coat than mane and tail colour, clear primitive markings (a distinctive dorsal stripe, horizontal striping on the back of the forelegs, often a transverse stripe over the withers), and the dark “dun mask” on the face. The dun gene also produces light guard hairs in the mane and the tail.
Silver dapple: dark coat lightened by silver gene.
The silver or silver dapple (Z) gene is a dilution gene that affects the black base coat colour and is associated with Multiple Congenital Ocular Abnormalities. It will typically dilute a black mane and tail to a silvery gray or flaxen colour, and a black body to a chocolaty brown, sometimes with dapples. The most common colours in this category are black silver and bay silver, referring to the respective underlying coat colour.
Champagne: various shades with metallic sheen.
The champagne gene is a simple dominant allele responsible for a number of rare horse coat colours. The most distinctive traits of horses with the champagne gene are the hazel eyes and pinkish, freckled skin, which are bright blue and bright pink at birth, respectively.
The coat colour is also affected: any hairs that would have been red are gold, and any hairs that would have been black are chocolate brown. If a horse inherits the champagne gene from either or both parents, a coat that would otherwise be chestnut is instead gold champagne, with bay corresponding to amber champagne, seal brown to sable champagne, and black to classic champagne.
Brindle: striped coat pattern resembling a zebra.
Brindle colouring in horses is extremely rare and in many cases is linked to spontaneous chimerism, resulting in an animal with two sets of DNA, with the brindle pattern being an expression of two different sets of equine coat colour genes in one horse.
Brindle colouring consists of irregular stripes extending vertically over the horse’s body and horizontally around the legs. It basically looks like your horse got caught out in a light, but persistent rain. Brindle horses can also have a dorsal stripe. It usually does not affect the head and legs as much as the body, with the heaviest concentrations of bridling being on the neck, shoulders and hindquarters. The brindling can also be on one side only.
Pangaré: lightening of colour on the muzzle, belly, and inner legs.
Rabicano: white hairs concentrated at the base of the tail and scattered on the body.
Rabicano, sometimes called white ticking, is a horse coat colour characterised by limited roaning in a specific pattern, typically appearing at the flank and top of the tail. Rabicano is distinct from true roan, which causes evenly interspersed white hairs throughout the body, except for a solid-coloured head and legs.
The word, “rabicano” is of Spanish origin – rabo meaning “tail” and cano meaning “white” – thus, it described a horse with white hairs in its tail.
What are the most popular and the most rare horse colours in the world?
While all horse colours have their unique appeal, some are rarer than others.
The title of the rarest horse colour often goes to the “Akhal-Teke metallic golden,” which features a gleaming, almost metallic, gold coat. This stunning colour is exceptionally scarce and is primarily found in the Akhal-Teke breed, originating from Turkmenistan. Their unique coat colour is the result of a special gene that gives them their distinctive sheen.
The title of the most popular horse colour varies depending on geographical regions and individual preferences. However, over the years, bay horses have consistently ranked among the most favoured. Their rich, deep colouring and black points give them a classic, timeless look that appeals to many (I personally love a nice, dark blood bay).