[1] “Grey color. Take a lot of good rubric and good ink, put them in a horn and let it stand for a night.” Hs.1028/1959 8°. end of fifteenth century – beginning sixteenth century. Stadtbibliothek Trier: fol. 28r. In: Braekman. 1997. Warenkennis, Kleurbereidingen Voor Miniaturisten En Vakkennis Voor Ambachtslui (15de E.): p. 140, rec. 50.