Yellowing - Expert Removal & Treatment Guide
Yellowing - Expert Removal & Treatment Guide
What is Yellowing?
Yellowing and color change in white marble and light-colored stone can occur due to various factors, including exposure to certain chemicals, improper cleaning methods, or natural aging processes. This discoloration can significantly affect the aesthetic appeal of the stone, making it appear dull and unattractive. It is essential to identify the cause of the yellowing to apply the appropriate treatment effectively.
How to Identify It
Yellowing presents as a uniform colour shift from white/light grey to cream, yellow, or golden across the entire surface - not as localised spots. Key distinction from stains: yellowing affects the whole surface evenly (compare a normally hidden area, like under a rug, with an exposed area), while stains are localised with defined edges. Common on white marble and light limestone. Causes include UV exposure (compare sun-exposed vs shaded areas of the same stone), iron oxidation within the stone (appears gradually from within), or reaction with certain sealers or adhesives (appears within weeks of application). Wetting the stone temporarily masks yellowing - if the yellow disappears when wet, it is surface-level; if it remains, the discolouration is within the stone.
Common Causes
- Exposure to acidic or alkaline cleaning products
- Improper maintenance or cleaning methods
- Natural aging and wear over time
- Staining from organic materials or pollutants
- Inadequate sealing or protection of the stone surface
Prevention
- Use pH-neutral cleaners specifically designed for natural stone, such as Lithofin MN Easy-Clean.
- Regularly apply a protective sealant like Lithofin MN Stain-Stop to prevent staining.
- Avoid using harsh chemicals or abrasive cleaners that can damage the stone.
- Clean spills immediately to prevent staining and discoloration.
- Maintain a consistent cleaning routine to preserve the stone's appearance.
Treatment by Surface Type
Natural Stone
Risk level: High
For surface yellowing: apply Lithofin MN Power-Clean diluted 1:3, leave 10 min, scrub gently, rinse. For deep yellowing from iron oxidation: use Lithofin Rust-EX as a poultice - apply thick paste, cover with cling film, leave 24h, remove and rinse. For prevention: seal with Lithofin MN Stain-Stop to prevent liquid penetration. For wax-induced yellowing: strip with Lithofin WAX-OFF first.
- White marble is extremely susceptible to yellowing
- Iron content in stone can cause yellow discoloration from inside
- Avoid bleach-based products that can worsen yellowing
Ceramics
Risk level: Low
Clean with Lithofin KF Intensive Cleaner to remove any chemical residues causing discoloration. For grout yellowing: use Lithofin KF Grout Cleaner. Rinse thoroughly and protect grout with Lithofin KF Grout Protector.
- Ceramic tiles rarely yellow unless exposed to strong chemicals
Artificial Stone
Risk level: Medium
For quartz composite: clean with Lithofin Composite Cleaner. For terrazzo: treat as natural stone - use Lithofin MN Power-Clean. If yellowing is from old sealant: strip with Lithofin WAX-OFF, clean, and re-seal with Lithofin MN Stain-Stop.
- Quartz composite can yellow from UV exposure
- Terrazzo with white marble chips can yellow like natural marble
Cotto Terracotta
Risk level: Medium
Strip old wax with Lithofin WAX-OFF or Lithofin TC Easy-Clean concentrated. Clean thoroughly with Lithofin WEXA. Once clean and dry, re-treat with Lithofin TC Classic Primer followed by Lithofin TC Classic Wax for a fresh appearance.
- Yellowing in cotto often comes from old wax layers trapping dirt
When to Call a Professional
If the problem persists after two treatment attempts, or if the affected area is large (>10m²), consult a professional stone restorer.
Find the right product
Use our Lithofinder to get a personalised product recommendation for your specific surface and problem.