Microbiologically induced aesthetic and structural changes to dimension stone

Abstract Dimension stone is natural rock prepared for building use. It rapidly colonised by microorganisms that cause discoloration (mainly cyanobacteria, algae and fungi) structural damage. Microbial mobilisation of ions leads to new superficial or internal deposits, weakening the structure. Cyanobacteria fungi may penetrate, filling pores creating spaces. Lichens, fungus/phototroph associations, colonise surfaces damage through ingrowing rhizines acid production. Initial degradation produces conditions suitable germination seeds higher plants further destruction. Emerging techniques elucidate stone-cell interactions control initial biofilm formation eventuates in disintegration are discussed.