The lunette which dates from 1371 is enclosed by a Gothic arch in marble in pure 14th century style. The artist of the fresco is unknown but one can detect the influence of the Florentine painter Niccolò di Tommaso who worked in Naples during this period. The fresco shows elegance of design and harmony of color, both of which were evident in the art of that time and suggest the influence of Giotto.

The lunette shows the Virgin on a throne with the Infant Jesus . They are flanked on the right by three men and on the left by three women. On the right, kneeling, is Count Giacomo Arcucci who genuflects and holds an architectural model of the Certosa up to the Virgin. On the left, also kneeling is Queen Giovanna I, protectress and benefactor of the monastery. She is clearly identifiable by the crown on her head and the golden lilies of the house of Angevin which rain down on her long blue dress. Standing immediately adjacent to the Virgin are St. Bruno, on the left, with his hand on the shoulder of the Queen and St. Giacomo, on the right, with his hand on the shoulder of the Count.

In the apex of the Gothic arch is a representation of the Holy Spirit painted in the form of a dove circled by angels with musical instruments. At the highest point in the arch is sculptured the sacred Lamb. In the middle of the architrave is the Angevin coat of arms in blue adorned with golden lilies which also appear on Giovanna’s royal dress. This coat of arms is fundamental to understanding the chronology of the construction of the monastery from 1371 to 1374 and its inspiration in the Certosa of San Martino in Naples. Its builder was most certainly Giacomo Arcucci, Count of Minervino, Lord of Altamura, royal advisor, and Secretary of State to Queen Giovanna I.