What are the best stone desalination methods?

Stone desalination is a critical process for preserving masonry and natural stone structures affected by salt accumulation. Over time, salts can cause efflorescence, spalling, and structural damage. Here are the most effective methods to combat this issue:

1. Poultice Desalination: A widely used technique involving absorbent materials like clay or cellulose applied to the stone surface. The poultice draws out salts as it dries, requiring multiple applications for thorough results.

2. Electrochemical Desalination: An advanced method using low-voltage electric currents to migrate salts away from the stone. Ideal for heavily contaminated structures but requires professional equipment.

3. Water Washing: Gentle rinsing with deionized water helps dissolve and remove surface salts. Avoid high-pressure washing, as it can damage porous stone.

4. Natural Ventilation and Drying: Allowing stones to dry naturally in well-ventilated areas can reduce salt crystallization. This passive method works best in dry climates.

5. Chemical Treatments: Specialized desalination products can break down salt crystals without harming the stone. Always test on a small area first.

For long-term preservation, combine desalination with protective coatings and proper drainage to prevent future salt infiltration. Regular maintenance ensures the longevity of stone structures.