Caring for marble flooring in Indian conditions

Why marble floors go dull

Marble is calcite, and calcite does two things that a granite floor does not. It dissolves in acid, so any sour liquid or acidic cleaner eats the polish where it touches. And it is soft enough that the sand carried in on shoes scratches it. Most tired marble floors have been worn down by the wrong cleaner and by grit.

Daily cleaning

Dry first, then wet. A dry mop or soft broom removes the grit before a wet mop drags it across the surface. Then a wet mop with plain water or a pH-neutral floor cleaner diluted as the label says. Wring the mop well: extra water does not clean better, it only takes longer to dry and leaves more water marks. Dry mop again in bathrooms and wherever the water is hard. Rinse the mop often, or it drags yesterday’s grit back across the floor.

Phenyl and acid cleaners

Acid cleaners for tiles and bathrooms, the ones sold for removing scale, are hydrochloric acid in various strengths. On marble they do exactly what they do to scale: dissolve it. One wipe leaves a dull patch that no cleaning brings back. Keep them out of a house with marble in it.

Phenyl is a harder case because it is so widely used. It is a disinfectant, not a stone cleaner. It leaves a film that builds up and dulls the polish over months, and some products in the market are acidic. A heavily diluted white phenyl now and then will not ruin a floor, but it is not doing it any good. A neutral cleaner is kinder to the stone. Vinegar, lemon and bleach are not marble cleaners either.

Hard water marks

Borewell and tanker water across much of Gujarat carries a lot of dissolved minerals. Every drop that dries on the floor leaves a little of them behind, and in a bathroom or beside the kitchen wash area that becomes a white haze or rings in a few weeks.

Prevention is drying: a squeegee or a dry mop after a bathroom is used, and wiping spills rather than leaving them to dry. Removal is gentle: a damp cloth with neutral cleaner, then a dry cloth. For a stubborn ring, a marble polishing powder worked in with a damp pad. Do not reach for an acid, because it will take the mark off and the polish with it.

Etching from lemon, vinegar and curd

An etch is a dull, slightly rough patch where acid has dissolved the polished surface. On a floor it comes from a dropped lemon, spilt curd, a fallen glass of nimbu pani, pooja offerings, or an acidic cleaner. It is not a stain and does not wash off. Small etches can be polished out by hand with marble polishing powder; large areas need a machine. Wipe acidic spills immediately.

Sealing and how often

A penetrating sealer sits in the pores of the stone and slows down what soaks in: water, oil, haldi. It does not stop etching, because etching happens to the surface, not inside it. On a floor, seal after the floor is polished and clean, let it cure as the label says, and re-seal when the water test fails: a few drops left for ten minutes that darken the stone mean it is time. For most living areas that is every one to two years; kitchens, bathrooms and entrance halls sooner. Do not seal a damp floor, and do not use the glossy coat-on-top products sold as instant shine; they wear unevenly and yellow.

Monsoon moisture

Monsoon humidity does two things to a marble floor. The polished surface gets a film of damp and becomes slippery, so use mats at doors and in bathrooms and keep the air moving. And on ground floors, moisture from below can rise through the slab, carrying salts that come out on the surface as white powdery patches. This is the stone drying out, not a stain. Brush the powder off dry, do not wash it in, and let the floor breathe. It usually stops when the ground dries. If it continues year-round, the problem is damp under the floor, and no cleaning product fixes that.

Rugs and grit

Grit is the main thing that wears a marble floor. A doormat outside and inside every external door, and shoes off at the door, remove most of it. Rugs protect high-traffic routes, but choose a breathable backing. Rubber-backed and foam-backed mats trap moisture and can leave a yellow outline that is very hard to remove. Lift them regularly and let the floor dry. Felt pads under furniture legs; never drag a bed or a cupboard.

What yellowing is

A white or pale marble floor that has gone yellow usually has one of three problems. The first is iron in the stone: many light marbles contain a little, and with moisture from below over years it oxidises to a rusty tone that is in the stone, not on it. Keeping the floor dry slows it; a poultice from a professional may lighten it; it rarely reverses fully. The second is build-up: layers of wax, phenyl film or a shine product that have gone brown. A stone stripper takes this off and the white floor is underneath. The third is rubber mats, or oil soaked in near a kitchen. Find the cause before you buy a product.

Re-polishing after years

A marble floor that has been scratched, etched and walked on for ten or fifteen years does not need replacing. A floor polishing crew with a rotary machine and diamond pads grinds the surface back, coarse to fine, wet, then brings up the shine with a finer pad and a polishing powder or crystalliser. If slab edges sit at different heights, the first pass levels them. A house takes a few days, there is slurry everywhere, and furniture must be out. Seal the floor afterwards and go back to a neutral cleaner, and it will last many more years.