Will acid damage Giallo Siena marble?
Yes, and permanently.
Answer
Is an etch on Giallo Siena marble the same as a stain?
Keeping the surface
An etch is the polish chemically taken off: a dull, lighter mark where acid has reached the surface. A stain is something in the stone or on it — oil, a plant, a mark — and it may be treated. An etch has to be re-polished; how long that takes is how long the stone has been out of use.
The figures
| Mark | What it is | Can it be cleaned off | Source |
|---|---|---|---|
| Etch | The polished surface has been chemically removed | No — it has to be re-polished | Published maintenance practice |
| Stain | Something in the stone or on it | Depends: a poultice for oil or a plant, a specialist for anything unknown | Published maintenance practice |
| Efflorescence | White powder — salts coming out of the slab | Brushed off and rinsed | Published maintenance practice |
| Chipped arris | A mechanical fault, not a chemical one | Not a cleaning matter | Published maintenance practice |
Why this stone behaves this way
Giallo Siena marble is calcite, and calcite dissolves in acid. When the acid takes the polished surface off, the surface below is the unpolished stone, which is lighter and duller. That is why an etch looks like a dull patch rather than a stain, and why no amount of cleaning brings the gloss back.
What these figures are, and what they are not The distinction matters because the remedy differs completely. Cleaning an etch wastes material and time and does not work.
Where these figures come from
- S8 lxcc.com — Giallo Siena product page (composition, acid sensitivity, sealing cycle, installation)
- S15 mggroupin.com — marble maintenance practice (sealing cycle, etching prevention)
Where to go next
On the same subject
More questions about Giallo Siena marble
How do you clean Giallo Siena marble?
With a soft cloth or a non-abrasive mop and a cleaner made for marble, neutral in pH.
This answer sits on the Keeping the surface page, with the rest of the questions about it.
Care and maintenanceAsk for a price
A thickness, a format, a finish, a quantity and a destination will get you a quotation for Giallo Siena marble.
Is an etch on Giallo Siena marble the same as a stain?