Pencil

Pencil is the gene responsible for what you see in the Saxon Breast Pigeon and Hana Pouters. It is also responsible for the Gazzi marking found in Modenas. It is relatively rare in other breeds.
Pencil Roller cock on Blue ground color.	These two Pencil birds are on a Blue ground color and are the same bird before the moult (left) and in adult plumage (right).	A Pencil cock on Blue
Recessive Red Pencil Roller hen	These two pictures are the same bird. This is a Blue Check Roller hen that carries pencil. Birds that carry Pencil can show a lot of bronzing, like this bird, or no bronzing at all.	Blue Check that carries Pencil showing the bronzing. Picture courtesy of Robert Bennion
Pencil on Blue Bar Picture courtesy of Robert Bennion	Pencil on Blue Bar Picture courtesy of Robert Bennion	Brown Pencil Picture courtesy of Robert Bennion
Young Pencil Picture courtesy of Robert Bennion	Picture of the tail of a bird that carries Pencil. This is a common expression. Picture courtesy of Robert Bennion