The Monastery of St. Catherine's in the Sinai contains major cycles of wall paintings dating from the 6th to the 15th century, as well as facings of Proconnesian marble slabs, joined so their veins create elegant symmetrical designs the base of the basilica. This extraordinay heritage is in critical condition. The marble facing has not been maintained for centuries, and is blackened by the smoke from lamps and candles. The paintings suffer from detachment from the support and blisters in the paint layer.
The CCA, Centro di Conservazione Archeologica, has been working since 2005 on conserving the mosaic of the Transfiguration in the apse of the basilica, one of the most famous and rare examples of early byzantine mosaic art. At the request of the monastic community, they also formulated a project for the consolidation, cleaning, conservation and enhancement of all the other works in the basilica. Now that the mosaic has been conserved, the next treatment will be to clean the marble facing, which will complete the final presentation of the apse area.