Casually googling horse colours and came across this. There is so many colours/variations i have never heard of! SOURCE
Standard Chestnut (Sorrel) One of the two basic horse colors. Chestnut horses produce no eumelanin (black pigment) in their hair, causing their coats to be reddish with a copper sheen. Chestnut comes in many shades, but the most common is standard chestnut, characterized by a carroty brown body with a mane and tail the same shade or only slightly lighter or darker. Black The second basic horse color. Black horses produce both eumelanin and pheomelanin (red pigment). They are uniformly black, save for the sunburnt brown hairtips of fading blacks. Bay A bay horse is a black horse whose black pigment is restricted to its “points” - mane, tail, legs, and ears. The result is a red-brown horse with a black mane, tail, and legs. Primitive Bay (Wild Bay, Faded Bay) A primitive bay horse has markedly less distinct black points than a typical bay horse. Black on the legs in minimal and tends to be concentrated around the pastern, knee, and hock. Standard Brown Many researchers consider brown simply a shade of bay. A brown horse is a black horse that has been lightened to brown, most noticeably in the “soft parts” - the muzzle, girth, flank, and quarters. Seal Brown Another shade of brown. This coloration is frequently mislabeled black. Seal brown horses are indeed very black, but they have brown hairs on their muzzle and other soft parts. This qualify them as brown. Red Dun A red dun horse is a chestnut horse affected by the dun dilution. This dilution lightens the horse’s body and gives it darker points and a dorsal stripe (a stripe down its back). Many duns also have shoulder stripes and zebra striping on their legs. A few also have cobwebbing on their foreheads, shadowing, and pale guard hairs. Grullo This is a black or dark brown horse affected by the dun dilution. It is sometimes called blue dun. The body is murky brown-gray to gunmetal silver with black points and markings. Dun The classic dun color, a bay horse under the influence of the dun dilution. It very closely resembles buckskin, but it possesses the tell-tale marking of a dun: a dorsal stripe. The horse pictured here also has a shoulder stripe, leg barring (zebra striping), and pale guard hairs around the mane and tail. Palomino A palomino horse is a chestnut horse possessing one cream dilute allele and one “normal” allele. The red pigment of the coat is lightened to give the horse a golden body and a white mane and tail. Unlike the similar-looking flaxen chesnut, palominos have a silver, not a copper, sheen. Black Buckskin A black buckskin horse is a horse possessing one cream dilute allele and one “normal” allele. The cream dilution only minimally affects black pigment so the horse can appear to be a dark, murky color (as pictured here) or it can appear to be nothing more than a faded black. Buckskin A buckskin horse is a horse possessing one cream dilute allele and one “normal” allele. Its body is lightened to a cream or golden color, but it keeps its black points. Like palominos, buckskins have silver sheens, not copper, which helps discern dark buckskins from light bays. Cremello A chestnut horse with a “double-dose” of the cream allele is lightened to a cremello. This pale cream coloration is often mistaken for white or albino (albinism does not exist in horses). Smokey Perlino A black horse with a cream “double-dose.” It is noticeably darker than the cremello, and typically has a mane and tail darker than its body. Perlino The bay version of cremello is called perlino. Though perlinos typically have a darker mane and tail than cremellos, they are indiscernible in many cases and require pedigree analysis to determine their true color. Gold Champagne A gold champagne horse is a chestnut horse affected by the champagne dilution. It resembles a palomino with a metallic sheen, but can be discerned from a true palomino by its pink, usually speckled, skin. Classic Champagne This is a black horse under the influence of the champagne dilution. Its body is murky gray-brown to rich chocolate with dark brown points. Its skin is pink and speckled. Amber Champagne The bay version of champagne, this pink-skinned horse is cream with dark brown points. Gold Ivory Champagne This horse is a palomino under the influence of the champagne dilution. It is almost indiscernible from cremello, but its speckled skin gives it away. Classic Ivory Champagne This is a smokey perlino horse with the champagne dilution. It has a pale body with reddish to warm grey-brown points. Its skin is pink and speckled. Amber Ivory Champagne An amber ivory champagne horse is a perlino horse affected by the champagne dilution. It is, many times, indiscernible from perlino, but it has tell-tale speckled skin and its mane and tail are typically chocolatey. Red Taffy A red taffy horse is a bay horse affected by the silver, or taffy, dilution which affects only black pigment (having no affect on chestnut-based colors). It appears to be a bay horse with a pale mane and tail (often streaked with black hairs). It is frequently mislabeled as flaxen chestnut, but it has dark legs, which flaxens lack. Chocolate Flax This horse is a silver dapple that lacks dapples. Silver Dapple The silver dapple is another shade of taffy on a black/dark brown base. It is a warm chocolate color with an ivory mane and tail and cream dapples throughout the coat. Blue Taffy A blue taffy horses is a black or dark brown horse under the influence of the silver/taffy dilution. This horse is bluish-grey or murky brown-grey with a silvery mane and tail. It may display dappling, though the pictured horse does not. Pearl (Barlink, Apricot) A recently discovered horse color, pearl governed by a recessive, “cream-activated” gene. In single doses (heterozygous), it does not manifest itself unless the horse possesses a cream allele (palomino, buckskin, black buckskin), in which case it will act like a second cream allele and cause the horse to appear cremello, perlino, or smokey perlino. When not interacting with the cream gene, pearl only manifests in double-doses (homozygous). The horse pictured here is homozygous pearl on a chestnut base. Flaxen Chestnut This is a chestnut horse under the influence of the flaxen gene. This gene only affects pheomelanin (red pigment), so it is only expressed in chestnut-based colors. It lightens the mane and tail and, many times, the lower legs. The horse represented here is a flaxen honey chestnut. Pangaré This is a modifier that strikingly lightens a horse’s underbelly, insides of the legs, forearms, buttocks, and muzzle. It can also lighten the area around the eyes and the entire lower legs. The horse pictured here is a flaxen chestnut with Pangaré modifications. Chestnut ‘Strawberry’ Roan A strawberry roan horse is a chestnut horse affected by the roan modifier. Roan horses have white hairs interspersed with base color hairs throughout their coats (though not on the head and legs). If injured, the hair that grows from the wound as it heals will be dark. For this reason, many roan horses have dark spots on them marking past scratches, kicks, and bites. Black ‘Blue’ Roan A black (blue) roan is a black horse affected by the roan modifier, giving the horse’s body a pale bluish color. Bay Roan A bay roan horse is a bay horse affected by the roan modifier. Brown ‘Blue’ Roan A brown (blue) roan is a brown horse affected by the roan modifier, giving the horse’s body a pale bluish color. The ‘Catch A Bird’ Anomaly Catch A Bird was an unusual thoroughbred stallion that appeared to be brown with white hairs arranged in vertical stripes throughout his coat. He had no unusually colored horses in his well-documented pedigree and, when bred, produced true roan horses. True roan did not previously exist in thoroughbreds (although “roan” is frequently used to describe graying chestnut or bay thoroughbreds, this is a misnomer). Catch A Bird was most likely a spontaneous mutant, a mosaic, or both. Other horses have been seen with a similar pattern, but testing is needed to determine their colorations’ true natures. Fleabitten Grey with Blood Mark Some greys never fully grey (become white), but are instead covered in tiny flecks of their base color (the horse pictured here is a chestnut). Rarely, these flecks condense to form a patch known as a blood mark. Dapple Grey Grey horses are born normally pigmented, but as they age, their hairs lose pigment causing them to gradually turn grey or white. Dapple gray horses grey in such a way that it forms a spotted pattern over their bodies. White-Grey A white-grey horse has fully greyed so that is has no color left in its coat. White-grey horses are often mislabeled as white, but their dark skin and black muzzles prove them to be greys. Sooty The sooty modifier causes the color of a horse to be considerably darkened and is usually accompanied by seasonal dappling. Sooty can severely distort a horse’s true color. Lemonsilla Lemonsilla is an unusual coloration caused by the sooty modifier on a palomino horse. It appears to be a dull gold horse with a dark mane and tail. Brindle This is a very rare horse coloration, characterized by dark vertical striping over the entire body. Several brindle horses have been found to be genetic mosaics. Rabicano Rabicano is an unusual modifier that seems to be closely linked to sabino. It is characterized by roan-like ticking originating from the belly, and white barring at the base of the tail. Tobiano Tobiano is a form of piebaldism (patches of no pigment) in which white seems to descend vertically from the spine and covers the legs. The head and chest tend to be dark, the withers and legs tend to be white, and the mane and tail tend to be bi-colored. It is pictured here in four degrees. Medicine hat is so named for the tendency of a largely white tobiano to retain pigment in the form of a “hat” on its head. Overo Overo is a form of piebaldism in which white does not tend to cross the spine or cover the legs, but instead stays to the middle of the body and covers the head, spreading horizontally. It is pictured here in four degrees. Splashed White Splashed white is a very rare form of piebaldism, characterized by a white lower half and dark upper half, as well as a completely white head. It is pictured here in three degrees. Splashed white horses tend to have blue eyes, and most, if not all, are deaf. Sabino Perhaps my favorite horse coloration, sabino is a form of piebaldism in which white appears to vertically ascend the body in jagged peaks. It is characterized by the presence of a chinspot, speared white on the legs, and white on the belly. It is pictured here in three degrees. The sabino-white is the true white horse. Its coat is pure white, its skin is pink, and its eyes are dark. It is not a true albino, as albinism does not exist in horses and albinos have pink eyes. Normal White Markings Normal white markings occur in solid colored horses and are restricted to the head and legs. It may or may not have a genetic basis. These markings include star (white spot on the forehead), stripe (narrow stripe down the face), snip (white on the nose, between the nostrils), blaze (very broad stripe down the face), stocking (white extending from the hoof to at least the knee), sock (white extending from the hoof, above or on the fetlock, but not to the knee), pastern (white extends from the hoof to below the fetlock), and coronet (a white ring above the hoof). Pictured here is a horse with a blaze and two socks. Incomplete sabino markings are frequently confused for normal white markings. However, sabino horses, no matter how little white they show, tend to always have a white chin. Horses with normal white markings tend to have dark chins, even if they sport a full blaze. Flash markings are aberrent white markings on the legs that do not extend down to the hoof. Ermine Spots Ermine spots are dark spots within the white of a sock, pastern, or stocking. They tend to concentrate around the coronet. Dominant White Dominant white horses are pure white with pink skin and dark eyes. They may exhibit freckling in certain areas of their body, particularly around the genitalia. Dominant white horses appear so similar to sabino-whites, it may be impossible to visually tell the two colors apart. DNA testing for the W gene will provide the answer. Varnish Appaloosa Varnish appaloosa is a modifying pattern in which the horse appears to be frosted with white over its bony prominences. Snowflake Appaloosa Snowflake appaloosa is a spotting pattern characterized by little white spots throughout the coat. Snowcap Blanket Appaloosa Snowcap appaloosas appear to have large white globs congregating on their coats. A congregation over the rump is called “blanket.” Spotted Blanket Appaloosa This is a spotting pattern resembling snowcap, but has spots of the base color throughout the white patches. Near-Leopard Appaloosa A near-leopard appaloosa is largely white with base color spots through the coat, as well as a head and legs that are the base color. Leopard Appaloosa A leopard appaloosa is completely white with base color spots throughout its coat. Few-spot Appaloosa A few-spot appaloosa is completely white with base coat spotting restricted to only a few areas, typically the face, legs, girth, and flank. The mane and tail are typically dark. Manchado Manchado is a very rare, nonheritable coloration that has only been found in a few unrelated Argentinian horses. It is believed to be caused by environmental factors. Manchado horses appear to be white have large dark patches the color of their base coats concentrated around their heads and legs. The largest spots appear on their barrel, towards their loins. Birdcather Spots Birdcatcher spots are round, white spots that resemble splattered paint when in high concentrations. They may appear anywhere on the body, but have been seen to concentrate around the elbow. They may have no genetic basis. Chubari Spots (Tetrarch Spots) Chubari spots are large, pale, egg-shaped spots that sometimes appear on graying horses. Lace Markings (Giraffe Markings) Lace markings are rare white markings that resemble netting. They tend to appear later in a horse’s life and grow with age. They spread from the spine (particularly the withers and croup) outward. Badger Face Badger faces appear as reverse blazes - a large dark stripe down the face surrounded by white. They tend to be linked to sabino patterns. Smuts (Bend Or Spots) Odd dark spots on a normal solid base coat. These spots may not have a genetic basis. Gulastra Plume A Gulastra plume is an unusually blonde tail. The famous racehorse Cigar sported a Gulastra plume. Mosaicism A mosaic is an individual composed of two or more genetically distinct populations of cells. If these populations belong two separate genetic individuals, the mosaic is called a chimera. Mosaic and chimeric horses may exhibit strange colorations if their populations of cells are not the same color. Pictured here is a horse with broad, distinct populations of chesnut cells and brown cells. Different mosaics may exhibit very different patterns, however. Some mosaics are brindled and others exhibit lacey, irregular patterns.
