Sealing. What it does, and what it does not.
A sealer buys you time to wipe up a spill. It does not stop etching, and it is not a coating. Here is what to expect from it.
Most people expect a sealer to make marble bulletproof. It does not. A penetrating sealer soaks into the stone and slows how fast liquids get in, so a spill sits on top long enough to be wiped up instead of soaking in and staining. That is the whole job, and it is a good one.
What it stops
Stains, mostly. Oil, wine and coffee that would otherwise go into the pores stay on the surface for a while. On travertine and limestone, which are more porous than marble, sealing is the difference between a floor that stains from every dropped chip and one that does not.
What it does not stop
Etching. Acid dissolves the polished surface of marble on contact, and it does that on top of the sealer. Lemon on a sealed benchtop still leaves a dull ring. A sealer is not a topcoat, and any product that claims to make marble immune to acid is a coating that will yellow, peel or trap moisture. We do not use them.
How often
Benchtops, vanities and showers, which see acid and water every day, usually every twelve months. Floors and tables in lower-traffic rooms, two years or more. The honest test is water: a few drops left ten minutes should bead. If they darken the stone, it is due.
The reminder
Every surface we seal goes on a list with the date, and you get a message when it is due. It is the simplest way we know to stop a sealed floor quietly becoming an unsealed one.
Related guides.
Related questions.
How often should marble be sealed?
It depends on the surface and what it takes. A kitchen benchtop or a shower, which see acid, oil and water daily, are usually resealed every twelve months. A floor or a table in a lower-traffic room goes two years or more. The honest test is the water bead: a few drops left on the stone for ten minutes should sit up. If they soak in and darken the stone, the sealer has worn and it is time. We add every surface we seal to a reminder list and message you when yours is due, so you do not have to remember. A sealer is not a coating sitting on top. A penetrating sealer soaks into the stone and slows how fast liquids get in, which buys time to wipe a spill before it becomes a stain. It does not stop etching, because acid attacks the surface of the marble itself rather than soaking into it, and nothing short of changing the stone prevents that.
What causes water marks on marble, and do they come out?
Water marks on marble are usually one of two things, and both come out. Around a basin or on a shower ledge, a white ring or haze is mineral deposit from hard water evaporating, which strips off. A dull ring where a wet glass or bottle sat is etching, where the acidity of what was in the glass has dulled the polish, and that is honed and re-polished. The two look similar and are handled differently, so a photo helps us tell you which you have. Neither is a reason to replace the stone. Hard-water marks come off with a mild descaling pass and a stone-safe pad, because the deposit sits on top rather than in the pores. Etching is the opposite: nothing was added, a thin layer of polish was dissolved away, so it is corrected with fine abrasives until the finish is even. Wet the mark with a finger: a mineral deposit vanishes and returns as it dries, while etching looks the same wet or dry.