Why the water is hard
Much of the Aube and the Marne gets its water from the chalk under the Champagne plain. Rain picks up calcium on the way through and comes out of the tap hard. In France hardness is given in French degrees (°f), and above about 30 °f is called very hard. Your commune's figure is on your water bill and on the Ministry of Health's tap water website.
The problem
Supermarket descalers, "anti-calcaire", are acids, citric, sulphamic, phosphoric or acetic. White vinegar is acetic acid. They work on ceramic tiles. On marble they take off the polish, then the stone. A dull, rough patch round a tap is usually the cleaning, not the water.
What we tell people
- Dry the stone after use, scale forms where water evaporates. A squeegee in the shower and a cloth by the sink do more than any product.
- Clean with a pH-neutral stone cleaner, or a few drops of mild washing-up liquid in warm water.
- Rinse and wipe dry, so the soap doesn't leave its own film.
- Take off light scale with a plastic scraper or a soft nylon pad on honed stone. Never a scourer on polished.
- No vinegar, lemon, limescale sprays, bleach sprays or cream cleaners.
Sealers
A hydrofuge slows down water, oil and coffee soaking in. It gives you time to wipe. It does nothing against acid. To know when to redo it, drop water on the stone. If it darkens within a few minutes, it's time.
Showers
That's where hard water shows most. Use a squeegee on walls and tray after every shower, run the fan or open the window for twenty minutes, and go for a honed tray rather than polished, which grips better too. See bathrooms.
Holiday homes
In a second home, the person most likely to damage the marble is a well-meaning cleaner with a bottle of anti-calcaire. Leave a pH-neutral cleaner in the cupboard and a note in French. "Marbre, pas de vinaigre, pas d'anti-calcaire, nettoyant pH neutre uniquement." That one line saves a lot of marble.
Kettles and coffee machines
Descale them in the sink or on a tray, not on the worktop, the drips land on the stone. Wipe the ring under the tap every evening. Left a week, it sets hard and someone reaches for the vinegar.
Softeners
A softener on the incoming supply stops most of the scale on taps and shower walls. That's a plumber's job, not ours. A filter jug changes nothing in the shower.
If the damage is done
Marks round taps come off by honing and repolishing on site, wet. Thick old scale is removed first. See restoration. On floors we can crystallise after.
Granite and quartz mind acid cleaners far less, which is why they get chosen for rentals, see marble or quartz. Call +33 7 45 20 76 39 with photos of the damage.
