|University Federico II
of Naples, Italy
The main conservation treatments of stone artifacts, besides cleaning, include Consolidation and Protection. Both consolidation and protection aim to mitigate the deleterious effects of various degradation factors, reduce the rate of deterioration of the constituent materials, and extend their duration in time.
In principle, all treatments should be, as far as possible, durable in time and reversible in nature.
Among modern materials that are used for such purposes, polymer-based materials are particularly interesting.
Usually consolidation and protection treatments are evaluated with proper laboratory tests before being applied in situ.
Consolidation of stone artifacts, by injection of the agent using a proper syringe. top: Microstructure of a section of a porous stone with a poor adhesion between grains
bottom: The consolidating agent penetrates inside the stone and cohesion is improved
Consolidation, a treatment that is applied to damaged artifacts, has the purpose to:
Consolidation treatment with a spray technique
- stabilize degraded stones, which lack cohesion at microstructure level;
- restore a sufficient degree of cohesion, so recovering the physical integrity and functionality of the item;
- reduce the rate of degradation of stones, with no major modifications of their appearance or their characteristics.
The following properties are necessary for consolidating agents:
- chemical and physical compatibility with the component minerals;
- fluidity at application time, allowing them to penetrate to the inside of artifacts and to impregnate the parts to be stabilized;
- capability of consolidating in situ and keeping the adhesion to stone surfaces.
A simple scheme of a consolidation treatment in porous stones is shown in the right figure.