A ring left by a glass on marble is almost never the water itself. It is either a hard-water mineral deposit, which wipes away with warm water and neutral soap, or an etch from whatever was in the glass — and anything citrus, fizzy or wine-based etches marble on contact. Wet the ring to tell them apart: a mineral film lifts with cleaning, while an etch vanishes while wet and reappears as it dries. Etched rings need polishing powder, not more cleaning.
Telling the two apart
Wet the mark with a little water. A stain stays visible and stays darker. An etch briefly disappears while wet — because the water fills the roughened surface and mimics the polish — then returns as it dries.
Stain or etch — the difference that decides everything
| Stain | Etch | |
|---|---|---|
| What it is | A substance absorbed into the stone’s pores. | Acid has corroded the polished surface itself. |
| How it looks | Darker than the surrounding marble. | Lighter, duller or chalky — sometimes only visible at an angle. |
| Usual causes | oil, coffee, wine, grease, ink, rust from metal | lemon, vinegar, wine, tomato, fizzy drinks, many household cleaners |
| The fix | Draw it back out with a poultice. | Re-polish with marble polishing powder. Deep etches need a professional. |
| Prevented by | Sealing. A sealer slows absorption, buying you time to wipe. | Nothing you apply. Only keeping acid off the surface — a sealer does not prevent etching. |
Marble damage, diagnosed
| What you are seeing | What it actually is | What to do |
|---|---|---|
| A dull, lighter patch | Etch — acid corroded the polish | Marble polishing powder. Cleaning will not touch it. |
| A dark mark that will not wipe off | Stain — something absorbed into the pores | Poultice, 24–48 hours, repeat as needed. |
| A ring where a glass stood | Usually an etch from the drink, sometimes hard-water minerals | Wet it: if it vanishes while wet, it is an etch. |
| Cloudy film across the whole surface | Soap residue or hard water, not damage | Rinse with clean water and buff dry. |
| A fine scratch you can feel | Physical abrasion — marble is soft | Polishing powder if light; a professional if you can catch a nail in it. |
| Yellowing over a large area | Often iron in the stone oxidising, or old sealer breaking down | This one is a professional job — DIY attempts usually worsen it. |
| A crack or chip | Impact or thermal shock | Professional. Epoxy repairs are colour-matched by eye and hard to do well. |
Frequently asked questions
Why does it come back after I clean it?
Because it is an etch. Cleaning wets the roughened surface and temporarily restores the look; drying returns it.
Do coasters actually help?
They are the single most effective thing you can do. Most etch damage on dining and coffee tables is glass-shaped.
Does this happen to honed marble too?
The etching happens, but it shows far less because there is no gloss to interrupt.
Related guides
Sources
- Natural Stone Institute — Cleaning Products for Natural Stone — view
This is one part of looking after stone furniture. For how the material behaves in the first place, and which pieces suit which rooms, see Marble Furniture: The Complete Buyer’s Guide.