The study of color in Pucelle's works cannot be isolated from the question of a workshop and collaborators behind the manuscript paintings attributed to the artist. This subject has been treated in depth by Kathleen Morand and François Avril, whose research has made it possible to better distinguish the various hands at work in the manuscripts. The minute analysis offered here of the color and techniques employed in the very many miniatures, historiated initials, and drolleries in the actual manuscripts returns to this question by distinguishing a number of technical practices applied on a shared formal basis along with a differentiation of color by manuscript. Analysis of manuscripts attributed to the master point to varied usage of color, line and modeling. This confirms the existence of a group of artists working together on certain works and isolates certain hands while posing the problem of their identification. The present study also puts analysis of color and technical processes to the test as criteria for identifying the hands. Although their diversity, or inversely, their consistency can certainly help to distinguish between the various illuminators involved, such analyses do not allow a definitive position to be taken or propose a reconstitution of the division of labor as Jean Pucelle, as chef d'atelier, might have organized it. The second question pertains to the reasons behind the original and rare choice of grisaille in manuscript painting (sometimes added to full color in the second volume of the Belleville Breviary ). The practice of gray monochrome painting or "camaïeu" is obviously at the heart of the matter. It must be placed at the core of the contemporary practice of the ink and camaïeu "pourtrait" in illuminations, and its correlation with metal and color in precious decorative objects.