Jean Bourdichon typically used complex mixtures of pigments to paint human flesh. For the portrait of Charles de Martigny, for example, the artist employed a dense network of fine stipples and hatching strokes in multiple tonalities of tan, brown, pink, red, orange, white, black, grey and blue over a pale orange base flesh tone. The main components of these layers are vermilion, lead white, earth pigments, ultramarine and probably azurite.
In contrast to the loosely painted faces of the other figures, the face of the bishop, a contemporary of Bourdichon, is shown in sharp focus.
