This clear glass was painting with "Jean Cousin," the term is used for the color of cementation obtained from iron compounds that varies from pink to warm brown depending on the amount of dilution applied. It is used for skin tones of faces or the color of hair, and its appearance is dull and translucent. Because the technique appeared only at the end of the fifteenth century, it provides a means of dating our fragment.
The angel's face is quite distinctive, with a high flat forehead, big eyes, and a short nose. The curving shape of this fragment suggests that it comes from a "soufflet" extracted from a larger monumental window. We can imagine this angel participating to a vast religious scene in a church at the end of the fifteenth century.