Bay horses come in various shades of red and reddish brown, but always have a black mane, tail, and lower legs. They sometimes have a mix of darker and lighter colored hairs in their coats.  Standard bay horses have a medium reddish brown shade with an even color all over and no mix of lighter or darker hairs. Some variations of bay horses are blood bay (a very dark blood-red color), mahogany bay (a bay that is so dark it almost looks black), and light bay (a light, yellowish shade of red). Black horses have black points and a dark black coat all over their body. There are no brown, red, or lighter colors on a true black horse.  White markings can appear on a black horse. They usually occur on its head or lower legs. These small markings don't classify the horse as a different color. Some black horses fade in color due to sun exposure over time. They are still considered to be black. Black horses that don’t fade in color over time are called jet black or raven black. Brown horses usually have have brown manes, tails, and lower legs with a dark brown coat. They have lighter brown or tan spots on the muzzle, shoulders, and flanks. Brown is sometimes considered a shade of bay horse instead of a separate color. In this case it is called a dark bay. Buckskin refers to a variety of yellow and golden-colored shades of horses with black points. Their colors range from light tan to golden yellow or orange shades.  Buckskin horses often have a long dorsal stripe running down the length of their back. A standard buckskin is called a yellow buckskin. They have a medium yellow coat color all over. Some examples of buckskin color variations are dusty buckskin (a dark brownish-yellow shade), golden buckskin (a dark golden shade), and silvery buckskin (a shade so light that it almost looks silver). Grullas have smoky gray hairs all over their body with a black mane and tail. Their lower legs are usually black as well. They often have a dorsal stripe, a stripe down the middle of their back, and sometimes a darker head. To consider a horse a grulla, each individual body hair has to be the same smoky gray color. The coat should not be a blend of white hairs and colored hairs.
Identify a bay horse by its dark red or reddish brown body color and black points. Distinguish a black horse by its entirely black coat, mane, and tail. Look for black points and light brown spots to identify a brown horse. Spot a buckskin horse by its yellow or golden coat color and black points. Recognize a grulla horse by their mousy, smoky-colored hairs.