In a remarkable copy of the Gospels dating from the fourteenth century, which once belonged to the Medicis (Gregory-Aland 16), the general run of the narrative is written in vermillion; the words of Jesus and angels are crimson and occasionally in gold; the words quoted from the Old Testament and those spoken by the disciples are blue; and, finally, the words of the Pharisees, Judas Iscariot, and the devil are black.

Bruce M. Metzger, Manuscripts of the Greek Bible: An Introduction to Palaeography, 18.