How to get a toilet bowl cleaner stain off a marble counter?

July 27, 2009 11:08 PM

I left a new bottle of toilet bowl cleaner on the bathroom counter while unpacking groceries. It leaked, and I didn't notice until the next day. Now there's a rough white stain on the counter (marble) that won't come off. Any ideas on how to remove it?
posted by shelayna to Home & Garden (5 answers total)

It's possible that it actually dissolved/corroded the surface of the marble. Calcium scale deposits are probably pretty similar to marble, chemically, and the toilet bowl cleaner might contain something designed to loosen or dissolve them. (The chlorine bleach which AFAIK is the main component of toilet owl cleaner shouldn't affect marble by itself, though.)

What active ingredients does the cleaner list?
posted by hattifattener at 11:41 PM on July 27, 2009

Marble is a form of limestone (calcium carbonate), and toilet cleaners that say they remove 'limescale' (calcium carbonate)will do a good job of dissolving limestone too. Are you sure the stain is sitting on the surface of the marble, or has it actually eaten the surface? Its the acid in the toilet cleaner which does the damage.
posted by muckybob at 11:49 PM on July 27, 2009

Nthing that it's not a stain, it's chemical etching. Part of the marble surface has been eroded away. If the damage is shallow then it's feasible to grind and polish it out, but this is a multistep process requiring specialized tools.
posted by jon1270 at 3:55 AM on July 28, 2009

(The chlorine bleach which AFAIK is the main component of toilet owl cleaner shouldn't affect marble by itself, though.) What active ingredients does the cleaner list?

Hydrochloric acid is a fairly common component of toilet bowl cleaner; I'd guess that this is the culprit.
posted by Johnny Assay at 5:02 AM on July 28, 2009

It shouldn't matter too much, but your vanity is most likely cultured marble, so whatever nasty chemical could've reacted with the marble dust or the polyester resin, more likely the marble dust.

Here's a quick tutorial on how to restore the finish.
posted by electroboy at 6:41 AM on July 28, 2009