Icelandic horses have like mentioned earlier a variety of colors
but there are four main colors dominating and that is white,
brown, chestnut and black. Some horsemen think they can
identify characteristics of the horse just by their colors.
Blue roans are likely the rarest color of roan horses, but they
aren’t a rare horse color pattern. … The most common horse
colors are bay, chestnut, dun, and black. Roans are typically
considered a fairly common horse color, and blue roans are
found in most horse breeds.