Colors with Undefined Names

34. Grullo Color 417 - #A99A86

Grullo is a color of horses in the dun family, characterized by tan-gray or mouse-colored hairs on the body, often with shoulder and dorsal stripes and black barring on the lower legs. In this coloration, each individual hair is mouse-colored, unlike a roan, which is composed of a mixture of dark and light hairs. The several shades of grullo are informally referred to with a variety of terms, including black dun, blue dun, slate grullo, silver grullo, silver dun, or lobo dun

Because the grullo color is not due to the gray gene, a grullo horse remains the same basic color from birth, though some minor shade variation may occur from summer to winter coats. If a grullo also carries the gray gene, it will be born a mouse tan-gray shade, but then lighten and eventually develop a white hair coat with age. Because black is less common in general than bay or chestnut, grullo is likewise less common than red duns or bay (classic or zebra) duns.