Lithofin BERO
Art. 017-11-B
Orange-brown rust dots start spreading across your new quartzite kitchen island and no alkaline cleaner shifts them. BERO steps in, dissolving iron oxide within minutes and washing away without leaving etch marks on acid-resistant stone.
What BERO Does
BERO is an acidic specialist cleaner for natural stone. With a pH of 1.5, its inorganic acids convert insoluble iron oxide into water-soluble salts and break down cement smears by attacking calcium silicate bonds. You wipe, wait 2 minutes, and watch rust, cement haze, and iron discoloration lift off basalt, granite, and quartzite at 15 m²/L.
When to Use
- Undiluted on rust spots in a bathroom built with basalt - 1:1 (neat) /pages/problem-rust-stains
- Neat removal of cement film on rough granite patio - 66.67 ml/m² /pages/problem-cement-residue
- Neutralising brown iron streaks on honed gabbro floor tiles - undiluted
- Cleaning quarry-sawn slate window sills after grouting - undiluted /pages/problem-general-cleaning
- Clearing efflorescence on acid-resistant concrete steps - undiluted /pages/problem-efflorescence
How to Apply
- Wet the surface slightly; this limits deeper acid penetration. (PT5M)
- Spread BERO undiluted with a white nylon pad or sponge at 66.67 ml/m². (PT5M)
- Allow 2-5 minutes contact; scrub lightly if stains persist. (PT5M)
- Rinse twice with plenty of clean water until pH is neutral. (PT5M)
Coverage is 15 m² per litre. No drying time: rinse immediately after reaction.
Surface Compatibility
BERO performs best on basalt, granite, slate, bluestone, sandstone, and concrete. These materials resist low-pH attack because of their silica-rich matrices (Mohs 4-7). The acid dissolves iron without etching their surfaces. Do not use on marble, limestone, or any stone that reacts with acid.
Choosing the Right Product
For day-to-day upkeep after rust removal, use Lithofin PRO Clean & Care. For long-term oil and water repellency, seal with Lithofin PRO Stain-Stop.
Pro Tips
- Always pre-wet joints; mortar absorbs acid faster than stone, preventing joint burn.
- Use warm water (30 °C) for rinsing; higher temperature speeds neutralisation by 20%.
- Test a 10 × 10 cm patch first; colour change indicates hidden calcite veins.
Product Details
Application
Compatibility & Safety
| Surface | Rating | Notes |
|---|---|---|
| Marble | Caution | Test on a small area first due to acid sensitivity |
| Granite | Good | Generally safe but test first |
| Limestone | Not-recommended | Acidic product may damage limestone |
| Sandstone | Good | Effective on dense sandstone; test first |
| Slate | Good | Safe for most slate types |
| Bluestone | Good | Generally safe but test first |
| Basalt | Excellent | Highly effective on basalt surfaces |
| Porcelain | Not-recommended | Avoid use on porcelain surfaces |
| Ceramic | Not-recommended | Avoid use on ceramic surfaces |
| Glass mosaic | Not-recommended | Avoid use on glass-mosaic surfaces |
| Concrete | Good | Effective on concrete surfaces |
| Quartz composite | Caution | Test on a small area first |
| Terrazzo | Caution | Test on a small area first |
| Terracotta | Not-recommended | Avoid use on terracotta surfaces |
| Cotto | Not-recommended | Avoid use on cotto surfaces |
| Clinker | Not-recommended | Avoid use on clinker surfaces |
Dosage Calculator
Use as directed for best results
Frequently asked questions
Can I use BERO on polished marble?
No. Polished marble is acid-sensitive and will etch immediately at pH 1.5.
How long should BERO stay on granite?
Leave 2-5 minutes. Longer contact is unnecessary because rust dissolves rapidly at low pH.
Will BERO remove deep iron spots in basalt?
Yes, but you may need a second application. Each pass penetrates about 0.2 mm.
Does BERO affect impregnators like Stain-Stop?
It can strip part of the sealer. Re-impregnate treated zones after rinsing and drying.
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