Urban pollution poses a significant threat to stone sculptures, causing discoloration, erosion, and structural damage over time. To safeguard these artistic treasures, several proven methods can be implemented.

1. Regular Cleaning: Gentle washing with pH-neutral solutions removes harmful pollutants without damaging the stone. Avoid abrasive tools that may scratch the surface.

2. Protective Coatings: Applying specialized sealants creates a barrier against acid rain, soot, and chemical deposits. Modern nano-coatings offer invisible protection while allowing the stone to breathe.

3. Strategic Placement: When possible, position sculptures away from high-traffic areas or install protective screens to reduce direct exposure to pollutants.

4. Microclimate Control: Surrounding vegetation can help filter airborne particles, but maintain proper distance to prevent moisture retention against the stone.

5. Professional Maintenance: Schedule annual inspections by conservation experts who can detect early signs of damage and recommend appropriate treatments.

For valuable historical pieces, consider installing micro-environmental monitoring systems to track temperature, humidity, and pollutant levels. Combining these approaches significantly extends the lifespan of stone artworks in urban settings while preserving their aesthetic and historical value.

Remember that prevention proves far more effective than restoration – implementing protective measures early saves both the artwork and conservation costs in the long term.