2. Mechanism of stone weathering and associated pathologies

Regardless of their nature and texture, building stones are the fruit of a long geological maturation, conditioned by an environment of genesis specific to their great diversity: volcanic lava flows for basalts, molten magmas for granites, sludge sedimentation for limestones, heating and compression of ancient limestones for marbles... In absolute terms, their age remains that of the time of their formation, which can range from a few hundred years for lavas to several hundred million years for granites. In addition to differences in mineralogical nature and age, the geological history of – rocks, including the diagenesis of – sedimentary rocks, is a component that can influence contrasting life expectancies.

• A first aggression thus appears during the geological history of the rocks that follows their genesis, when the episodes that punctuate...