Earning the title of darkest color thanks to its total absorption of light is none other than black. Alongside white, black is one of the first recorded colors used in art, the pigment created by paleolithic who used charcoal, burnt bones, or various crushed minerals. Throughout much of history, black has been a symbol of evil, (such as the Greek mythology underworld), mourning, sadness, and darkness. However, in Ancient Egypt, the color had positive connotations of protection and fertility.
On a horse black can be very striking and look simple and sophisticated. It also compliments well with any other colours and suits most coat colours - even black.