The conservation work on the archaeological finds of the Roman Forum currently underway is part of a wider project of planned maintenance of the artifact of the Parco archeologico del Colosseo, aimed at recovering and enhancing the architectural decoration of the grandiose buildings of the Roman Forum and Palatine Hill. This project in the past years has involved the conservation of the architectural decoration of the Temple of Vesta and the coloured marbles of the lower peristyle of the Domus Augustana on the Palatine, as well as various marble artifacts, such as columns and capitals, located along the visitor route. The activities planned for 2024 consist in cleaning the architectural decoration elements located along the Via Sacra, in the area of the Basilica Aemilia and in the central area of the Forum. The maintenance of the marble artifacts is aimed at guaranteeing their best conservation, restoring their correct legibility and includes, if necessary, moving some of them to improve their visibility

• Conservation status

  The problems encountered are mainly related to prolonged outdoor exposure. The surfaces show erosion and decohesion due to the persistence of atmospheric phenomena, they are covered with a dark patina of biological origin and, in less exposed parts, show in some cases black crusts due to long exposure to atmospheric pollutants.

• The marble decoration of the Basilica Aemilia

  The southern wall of the Basilica Aemilia, in its internal front, still preserves some parts of the original marble decoration consisting of wall slabs in cipollino marble and its preparation in pozzolanic mortar in which small marble fragments are inserted, which had the ancient purpose of providing flatness to the marble slabs that would have been applied to it; along the foot of the wall there is still a wainscoting in ancient “Giallo Antico”marble.

  Also belonging to this wall are the white marble jambs, believed to belong to the ancient entrances to the basilica, incorporated in the recent past in a cement mortar to mark the entrances to the room.

  The present intervention aims at cleaning and preserving these valuable marble elements and the white marble elements decorated with acanthus scrolls and heads placed along the path, also in order to allow visitors to better appreciate the surfaces and the original decorative party currently hidden by layers of deposits and biological patinas.

• The marble architechtonical decoration of the Via Sacra and the central area of the Forum

  The marble elements located along the route of the Via Sacra and in the central area of the Forum are placed on brick walls or, in most cases, on grassy surfaces in direct contact with the ground: the fragments are exposed to the weather and are subject to degradation factors related to the climate, direct contact with biodeteriogens of various kinds and the deposition of dust and pollutants due to vehicular traffic in the immediate vicinity.

   

  The forms of degradation found on the artefacts are:
  •surface deposits such as dust and soil

  •black crusts and carbonate incrustations

  •animal droppings

  •loss of stone cohesion

  •cracking, fracturing and flaking

  •biological patina: algae, lichens, mosses and the presence of vegetation

  •oxidation of metal elements

  •staining

   

   The conservation intervention consists of the following operations:

  •removal of dust by means of brushes and vacuum cleaners

  •cleaning of the surface and removal of deposits with water or laser beam instrument

  •removal of biological patinas covering the surface

  •mechanical removal of the most tenacious encrustations

  •consolidation of decoached surfaces with nanocalcium in water

  •restoration of the adhesion of small scales

  •treatment to stop oxidation and protect metal elements

  •filling and micro-infilling of cracks, fractures and missing parts with lime-based mortar

  •surface protection to slow down the repetition of degradation.

  •drafting of Technical Report, graphic and photographic documentation of the intervention before, during and on completion of the work

• We conduct conservation works that aim at restoring surfaces according to the criterion of minimum intervention, respecting the ancient material, combining tradition, innovation and sustainability. In the name of respect for the ancient material, we exploit the synergy between ancient techniques and innovation borrowed from scientific research.

  An example of this is on the one hand the use of mortars formulated using the same ancient materials and procedures, and on the other the use of technological innovation represented by modern nanotechnology. Cleaning is performed with water alone and if necessary with laser instrumentation; traditional surface consolidating and protective products have been replaced by formulations that use nanometric molecular components, abandoning traditional solvents in favour of aqueous dispersions. These products offer superior performance compared to those in use in the past and have the advantage of not being harmful to the operator and the environment in which they are used; these formulations are not conveyed, as was previously the case, by solvents -toxic to the operator and the environment- but by water. The intervention is also guided and verified in its effectiveness by non-destructive scientific investigations that allow the characterisation of materials and degradation without damaging the ancient material.

• Materials and techniques

  • cleaning

  We conduct surface cleaning of stone materials with water and if necessary with laser instrumentation, which offers the advantage of being a very selective and adjustable method depending on the surface: we limit the use of chemicals and reduce the use of mechanical instruments on ancient stone

  • mortars

  we prepare mortars equal to the old ones usingnatural hydraulic lime, pozzolan, brick powder and river sand and apply them according to the same methods and procedures as in the past

  • stone consolidation and protection

  We replace traditional products with inorganic nanometric formulations such as nanocalci in water dispersion that offer better performance without the use of solvents so that interventions are environmentally sustainable and not harmful to the operator