New nanomaterials for consolidating stone
In order to evaluate the application of nanolime on hypogeum wall paintings, laboratory-made samples have been realized by using real specimens coming from two different hypogeum sites.
The true samples were very small so it has not been possible to treat them directly.
In these last years the nanolime has been applied widely, but despite the rapid increase in the literature on nanolime as a conservation material, it is today necessary to set up more technical and practical studies focalized on real specific cases.
For practitioners, it is important to have a broader range of published case studies that describe the nanolime treatment to different environmental situation .
The deterioration phenomena are caused by microclimatic conditions and thermohygrometric exchanges between walls and the microclime and presence of light and visitors flow .
The combination of water, air, and light interaction with the artefacts structures activates several degradation processes, interesting the various degradation phenomena: cohesion, crumbling, pulverization, concretion and/or biological patina growth.
The same authors  have also studied the strong influence of both relative humidity and particle size on the carbonation rates of lime pastes and lime mortars.Recently the employment of nanolime in the consolidation treatments of decorative carbonate matrix surfaces had a great development, thanks to multifunctional use in calcium standard-sized particles treatments.However, while the use of the nanostructured materials is described in several specialized papers, the information about the best conditions of applicability of the nanolime and its related potentiality for the consolidation in hypogeum environment is rarely considered.Nanotechnologies and nanolime, as consolidating materials for architectural and stone surfaces , have been developed mainly in the last years, for the capability to solve several problems connected with conventional lime treatments, such as incomplete lime carbonation process, limited depth penetration, and the formation of thin white superficial layers .
The materials in nanodimensions have specific chemical and physical properties, linked to the physical and chemistry properties of very small particles with respect to the massive materials .
Center of Sciences Applied to the Protection of Environment and Cultural Heritage-“Sapienza” University of Rome, Piazzale Aldo Moro, 00185 Rome, Italy Received 17 July 2013; Revised 4 December 2013; Accepted 5 December 2013; Published 20 January 2014Academic Editor: Alan K. For a long time the conservation of archaeological artefacts has been based on the principles of compatibility and minimal intervention.