Several artefacts inside the church were restored: the Altar of the Santissimo Crocifisso, and the altar of Santa Maria della Consolazione, located in the left and right aisles, respectively. Both are carved in local stone (calcarenite), with traces of colouring, visible on the sculptures and architectural mouldings, and fresco decorations present in the spaces behind them.
The cladding of the two columns and the large gilded frame of the central altar in the nave received conservation treatment, as well as several gilded wooden frames, residual parts of a large painted and gilded wooden altar machine pertaining to the altar of San Giuseppe, and two little wooden doors covered with brass foil, pertaining to the hallway of the chapel with the altar of the Santissimo Crocifisso.
In the course of the work, approximately 170 fragments of fresco decorations from excavations in the past in the underground spaces of the church were also catalogued, documented and restored; in agreement with the Superintendency, the fragments were temporarily stored in the Diocesan Museum of the Curia.

Nature of the interventions

During the conservation works, in addition to the restoration operations, diagnostic investigations were carried out to determine the origin and nature of the contaminants present on the surfaces and, in parallel, environmental conditions were monitored. A study of the constituent materials and alteration products related to the incidence of different deterioration factors was also carried out.
For the stone parts, the intervention was carried out in the initial phase, with the mechanical removal of salts from the surfaces, avoiding the use of water, a potentially very harmful medium under the environmental conditions observed. A water-based biocide product was used only to disinfect the microorganisms.
Further restoration work consisted of consolidation and plastering carried out mainly to secure the parts in precarious stability. The plasters covering the columns of the central altar, which were seriously compromised due to heavy salt efflorescence, were reclaimed and restored.
The restoration of the wooden artefacts was aimed at consolidating them, but it was also an opportunity to rediscover their precious finishes: the metal foil of the panels received a cleaning that brought to light the original gilding.
All the restored wooden artefacts were placed in containers suitable for their preservation, pending their transfer to museum settings.
The wall decorations in the space behind the altar of the Santissimo Crocifisso were brought to light by removing thick surface layers of salt deposits mixed with the remains of various repainting.
In the chapel of San Canione, at the back of the altar of Santa Maria della Consolazione, thick and continuous patinas of salts were removed superficially, to control the speed of reformation.
The observations made during the work provided all the elements needed to define the plan for future controls, maintenance and restoration.