Polished marble
A calcium carbonate stone with a polished finish. Chemically attacked by acids, including household ones, and the damage is permanent.
What not to do
Acetic acid (vinegar) is unsafe on Polished marble
Unsafe
Do not do this. The risk is established, and it is described below.
Etching is chemical removal of the stone, not a stain. It cannot be cleaned off and the surface has to be re-polished.
Precautions
- Test on an inconspicuous area first
Evidence
Strongly supported
Sources
Care & Cleaning of Natural Stone
Natural Stone Institute · Trade or professional body
Relied on for: That products containing lemon, vinegar or other acids may dull or etch calcareous stones, and that calcareous stone is sensitive to acidic solutions. (states this directly)
Kirk-Othmer Encyclopedia of Chemical Technology
John Wiley & Sons · Reference work
Relied on for: That acids react with calcium carbonate to form soluble salts. (background and mechanism only)
Citric acid is unsafe on Polished marble
Unsafe
Do not do this. The risk is established, and it is described below.
Precautions
- Test on an inconspicuous area first
Evidence
Strongly supported
Sources
Care & Cleaning of Natural Stone
Natural Stone Institute · Trade or professional body
Relied on for: That calcareous stone is sensitive to acidic solutions and that acids may dull or etch it. (states this directly)
Kirk-Othmer Encyclopedia of Chemical Technology
John Wiley & Sons · Reference work
Relied on for: That acids react with calcium carbonate to form soluble salts. (background and mechanism only)
Hydrochloric acid is unsafe on Polished marble
Unsafe
Do not do this. The risk is established, and it is described below.
Precautions
- Wear gloves
- Wear eye protection
Evidence
Strongly supported
Sources
Cleaning & Maintenance Guidelines — Gardens & Driveways
Marshalls plc · Manufacturer documentation
Relied on for: That limestones and marbles must not be acid cleaned because hydrochloric acid dissolves them. (states this directly)
Care & Cleaning of Natural Stone
Natural Stone Institute · Trade or professional body
Relied on for: That calcareous stone is sensitive to acidic solutions which may dull or etch it. (states this directly)
Oxalic acid is unsafe on Polished marble
Unsafe
Do not do this. The risk is established, and it is described below.
Evidence
Supported
Sources
Care & Cleaning of Natural Stone
Natural Stone Institute · Trade or professional body
Relied on for: That calcareous stone is sensitive to acidic solutions and that lemon, vinegar and other acids may dull or etch it. (states this directly)
Precautions
- Test on an inconspicuous area first
In detail
Marble is a metamorphic rock composed mainly of calcium carbonate. That single fact governs almost everything about cleaning it. Calcium carbonate reacts with acids, so any acidic cleaner — vinegar, lemon juice, citric acid descaler, many limescale and bathroom products — attacks the stone itself rather than only what is sitting on it. The result is etching: a dull, slightly rough mark where the polished surface has been chemically removed. Etching is not a stain and cannot be cleaned off, because there is nothing on the surface to remove. Restoring it means re-polishing the stone. The stone trade draws this distinction explicitly, noting that some substances etch without staining and others do both — which matters because the two need opposite responses, and treating an etch mark as a stain leads to progressively harsher cleaning of a surface that has nothing on it. Marble is also porous enough to absorb oils and pigments, which is why spills are a timing problem as much as a chemistry one. Impregnating treatments reduce absorption; they do not make the stone acid-resistant, and a treated marble worktop etches just as readily as an untreated one.
Properties
Sensitivity
- Acids
- Sensitive
- Alkalis
- Not known
- Chlorine bleach
- Not known
- Heat
- Not known
- Abrasion
- Sensitive
- Porous
- Sensitive
“Not known” means nobody has established this, not that the material is unaffected.
What works
Neutral cleaner is safe on, in specific conditions, Polished marble
Safe only in specific conditions
This is only appropriate within specific limits. Outside those limits, no claim is made.
Only within these limits:
- A neutral cleaner, stone soap, or mild washing-up detergent in warm water
- No acidic or alkaline additive of any kind
- Test an inconspicuous area first on any stone whose finish is unknown
The stone trade gives the same recommendation for acid-sensitive and acid-resistant stone alike, which means the compatibility question does not have to be resolved before cleaning.
Precautions
- Test on an inconspicuous area first
Evidence
Supported
Sources
Care & Cleaning of Natural Stone
Natural Stone Institute · Trade or professional body
Relied on for: That stone surfaces are cleaned with a neutral cleaner, stone soap, or a mild liquid dishwashing detergent and warm water. (states this directly)
Blotting is appropriate for Polished marble
Safe in the conditions described
Authoritative guidance supports this combination, within the conditions described below.
From the source's preventive section, which is about avoiding the problem rather than treating it.
Only within these limits:
- Immediately, with a paper towel
- Blot rather than wipe — wiping spreads the spill
- Followed by the routine neutral-cleaner wash where a mark remains
The instruction is one sentence and it is the whole of the emergency response the authority gives for a spill on stone.
Evidence
Supported
Sources
Care & Cleaning of Natural Stone
Natural Stone Institute · Trade or professional body
Relied on for: That a spill on natural stone is blotted with a paper towel immediately and the area is not wiped, because wiping will spread the spill. (states this directly)
Dry soil removal is appropriate for Polished marble
Safe in the conditions described
Authoritative guidance supports this combination, within the conditions described below.
Grit is the abrasive, and prevention is where it is controlled.
Only within these limits:
- A CLEAN, NON-TREATED, DRY dust mop — a treated mop is not what is cleared
- Frequently, because the control is removing grit before it is walked in
- Mats and rugs with slip-resistant backing to reduce what arrives
- Vacuum attachments and wheels checked for wear, which scratch when worn
The trade body's preventive programme is that what damages a stone floor is abrasive grit carried onto it, and that frequent dry removal is the control rather than more washing.
Precautions
- Test on an inconspicuous area first
Evidence
Supported
Sources
Care & Cleaning of Natural Stone
Natural Stone Institute · Trade or professional body
Relied on for: That interior stone floors are dust-mopped frequently with a clean, non-treated dry dust mop, that mats and rugs with slip-resistant backing minimise abrasive material reaching the stone, and that a vacuum's worn attachments or wheels may scratch. (states this directly)
Where the answer depends
Controlled resurfacing is appropriate for Polished marble
Depends on the manufacturer
This depends on the specific product or finish. Check the manufacturer's own instructions before proceeding.
The authority's answer to etching is that it is not a cleaning problem at all.
Precautions
- Consider professional help
- Test on an inconspicuous area first
Evidence
Supported
Sources
Care & Cleaning of Natural Stone
Natural Stone Institute · Trade or professional body
Relied on for: That etch marks are addressed by contacting a professional for re-polishing rather than by any cleaning treatment, and that acidic products including lemon and vinegar may dull or etch calcareous stones. (states this directly)
Why
- Polished marble is explained by Etching versus staining
- Polished marble is explained by Water purity and aggressiveness
- Polished marble is explained by Damage versus soiling
Related
- Polished marble is commonly affected by Grease
- Polished marble is commonly affected by Soap scum
- Polished marble is commonly affected by Limescale
Hacks and claims involving this
- Sealing stone makes it stain-proof Does not work
- Natural cleaning products are safer Does not work
- Mixing vinegar and bicarbonate of soda Does not work
- Spraying hydrogen peroxide and vinegar in sequence Does not work
- Vinegar as an all-purpose cleaner Disputed
- Steam cleaning sanitises without chemicals Unresolved
- Fine steel wool for hard-water marks on stone Supported
- Using a stone cleaner on a quartz worktop Does not work
- One spray for the whole bathroom Does not work
When the obvious answer is wrong
How do I remove limescale from a marble shower without ruining the marble?
Marble is also calcium carbonate. The acid cannot distinguish between carbonate deposited by hard water and carbonate that is the stone itself, so it dissolves both. The result on the stone is etching: a dull, slightly rough patch where the polished surface has been chemically removed. It is not a stain and there is nothing left on the surface to clean off.
A different kind of treatment works: Take the mechanical route rather than the chemical one. The stone trade's stated treatment for surface accumulation of hard water — what it calls water spots and rings — is to buff with dry 0000 steel wool, which is fine enough to lift the mineral film without cutting the stone, and involves no acid at all. Work on the deposit only, keep it dry, and stop as soon as the film has gone. Prevention does more than any treatment here: a squeegee after each use removes the water before it can evaporate and leave its minerals behind, which is the moment the deposit is actually created. If the surface is already dull in patches rather than filmed, that is etching rather than scale, no cleaning method will touch it, and re-polishing is a job for a stone restorer.
Sources for this page
Sources
Care & Cleaning of Natural Stone
Natural Stone Institute · Trade or professional body
Relied on for: That calcareous stone consists primarily of calcium carbonate and is sensitive to acidic solutions, that lemon and vinegar dull or etch it, and that etching is distinct from staining. (states this directly)
Kirk-Othmer Encyclopedia of Chemical Technology
John Wiley & Sons · Reference work
Relied on for: That acids react with carbonates to form soluble salts and carbon dioxide. (background and mechanism only)