The Friesian horse is black. While mares and geldings sometimes can be chestnut or dark bay, in order to be registered as a purebred Friesian, stallions must be black. (Even stallions shown ...

Friesian horses are renowned for their luxurious manes ... They can come in other colors too including chestnut, bay, brown, and grey. Horsey Hooves pointed out, "Though rare, there are chestnut ...