Innovative treatments for stone conservation

Monuments are commonly weathered by physical, chemical and biological factors. Taking into account those made with calcareous stones, the material, due to calcite leaching, increases the porosity and decreases mechanical characteristics. The products applied for stone conservation have some drawbacks and they, actually, can not fully satisfy the achievement of their safeguard. Thus the monumental buildings repair and maintenance sector needs innovative conservation strategies and products, specifically tailored. Starting from recently application of old methods, based on the use of lime-water, new approaches have been attempt and tested, based on biomineralization processes which induce the grow of new calcite crystals inside stone porosity. This can be achieved either with the application of calcinogenic bacteria or using specific organic macromolecules extracted from marine shells.