In the back of the Chapel are three stone panels.
   

In the center one, Mary holds the child Jesus, encircled by seven symbols that depict the traditional joys of Our Lady. To see them better, click on this small view. These joys are (clockwise from the upper right): The Annunciation (symbolized by Gabriel's 'Ave' and a fleur-di-lis) Visitation to Elizabeth (two converging angels) Birth of Christ (the manger containing the 'IHS' - the first letters of Jesus' name in Greek) Coming of the Wise Men (three crowns and a star) Finding of Jesus in the Temple (Chi-Rho, the first two Greek letters of the word 'Christ' and bible scroll) Resurrection (flowering Cross) Her Coronation in heaven (crown on lily).

The panel to the right of this honors Mary as the Queen of Sorrows.  The seven swords represent the sorrows of Maryn, which pierced her heart, as Simeon predicted in Luke 2:35.

The panel to the left honors Mary as channel of grace, using more imagery from the Book of Revelation: Mary, the lily with the moon and the twelve stars (the Apostles). Through her, great graces have come to the world from the throne of God (triangle and dove).