Vatican archaeologists using lasers have burned off a thick crust of calcium carbonate from the walls of a Rome catacomb to reveal what could be the oldest paintings of the apostles.
The frescoes of Sts. Peter, Andrew and John — along with one of St. Paul that was discovered last year near the end of the Pauline year — date back to the fourth century and are located in the Catacombs of St. Thecla in the burial place of a noblewoman.
Barbara Mazzei, director of the restoration work, told Catholic News Service that when restorers first entered the chamber two years ago a white crust from 1 millimeter to 4-5 centimeters thick covered the walls.
In the past, restorers used small scalpels and brushes to remove the accumulations, but some paint would inevitably be rubbed off. Mazzei suggested the laser method to the Vatican after attending an art restoration conference where presenters explained how lasers were being used on above-ground frescoes.
The new approach required carefully firing a laser across the surface of the catacomb images. The method burned off the white deposits and, thankfully, allowed restorers to preserve the paintings’ beautiful colors.