Alkali Efflorescence Treatment: Symptomatic and Radical Approaches for Stone Protection and Restoration

Overview of Efflorescence Issue

The protection against stone efflorescence and rust spots primarily relies on waterproofing. Stones have about 0.8% water absorption rate and many capillaries. Water carrying alkaline substances from cement, mortar, or within the stone itself rises to the surface and forms spots upon evaporation.

Radical Approach

1. Dehumidification and Cleaning

• Start with 150# dry grinding to open pathways, akin to "prepping the skin" before surgery.

• Clean off existing alkaline substances.

2. Apply Rust Remover

• Use products like "Ya Lun R96 Stone Rust Remover," applying it sparingly but frequently.

3. Apply Protective Agent

• Apply stone protective agent and cure for 72 hours.

4. Grinding and Stain Resistance Treatment

• After grinding flat, conduct stain resistance treatment using fluorine-containing protective agents.

5. Sealing Capillaries

• Use marble crystal hardener for crystallization and polishing to form a crystal film.

6. Regular Maintenance

• Regularly maintain the crystal film to preserve its effect.

Although the radical method is quick and effective, it is cumbersome and has a higher upfront cost.

Symptomatic Approach

The symptomatic approach mainly involves repeatedly performing crystallization polishing and applying protective treatments (applying oily stone penetrating protective agents and grinding) during dry weather. The entire process is lengthy, taking about 2 years.

Outdated Practices

In the past, stone waxing and polishing were popular, but this actually accelerates the yellowing and degradation of stone. Wax clogs the stone's capillaries, preventing water evaporation and increasing the exudation of alkaline substances. Instead, use a dedicated protective agent that forms a protective film inside the capillaries.