How does acid rain degrade marble figurative sculptures?

Acid rain poses a significant threat to marble figurative sculptures due to its chemical interaction with calcium carbonate, the primary component of marble. When sulfur dioxide and nitrogen oxides in the atmosphere dissolve in rainwater, they form sulfuric and nitric acids. These acids react with the calcium carbonate in marble, converting it into soluble calcium sulfate or calcium nitrate. Over time, this chemical weathering causes the marble surface to dissolve, leading to loss of intricate details, pitting, and structural weakening.

The process accelerates in urban areas with higher pollution levels, where sculptures may also suffer from soot and particulate accumulation. Preventive measures include applying protective coatings, regular cleaning, and relocating vulnerable artworks indoors. Understanding this degradation process is crucial for preserving cultural heritage and historical artifacts. Conservation efforts must balance public display with long-term protection against environmental damage.