The condition of the mosaic
The mosaic, which covered an area of 180 square meters, was not preserved in good condition. Its substrate had given way in many areas, the layer of tesserae had become detached or was only loosely attached to the substrate, and due to the loss of tesserae there were many destroyed sections (gaps), chiefly around the perimeter of the apse.
Conservation of the mosaic
The mosaic’s conservation was done in situ and involved the following:
• stabilizing of the detached surface layer which carries the tesserae on the substrate with compatible mortar
• stabilizing isolated tesserae on the substrate with compatible mortar
• restoring destroyed sections with compatible mortars or with mortar compatible with that of the substrate, depending on location.
