This photo is of the relics of the Passion of Our Lord which are also in Santa Croce in Gerusalemme. Notice the reliquary on the bottom left. It contains a relic of one of the Sacred Nails. St. Thérèse of Lisieux visited this basilica, and mentions it in her autobiography. She said that her hand was the only one small enough to reach inside the reliquary, and that other pilgrims were handing their Rosaries to her so that she could touch them to the Sacred Nail.