Marble - does etching remove anti-stain sealant?
I'm sure this has been discussed before but my searches don't turn up exactly what I'm wondering.
I know that marble etches *and* that it can be sealed so that it doesn't stain (in theory). If etching is a sort of erosion of the surface, why doesn't the etching agent also remove the anti-stain protective sealant barrier as well?
IOW, why will red wine etch, but not stain?