Etching is not staining
Etching is a chemical reaction that dulls the finish where an acid touched the stone. Staining is absorption of a substance into the stone. They look similar from a distance but need different treatments.
What to keep off marble
Vinegar, lemon, wine, tomato products, many bathroom cleaners and anything labeled as a descaler. Abrasive pads also flatten the polish over time.
What to use instead
A pH neutral stone cleaner or plain warm water with a soft cloth handles daily cleaning. Blot spills rather than wiping them across the surface.
Everyday habits that help
Trays for cosmetics and oils, cutting boards in the kitchen, coasters under glasses and drying the surface after cleaning. Small habits prevent most of the damage we are called about.
When to call
Widespread dullness, deep etch marks or a surface that no longer responds to cleaning should be assessed. Refinishing is possible in many cases, but the extent of the damage sets the expectation.
Pending business confirmation