Dear Melissa:
The acid corroded (etched) the surface of your marble. If it would have been a different and milder acid, such as contact lens cleaners, aftershave or other fragrances, etc., I would encourage you to consider a good marble repair kit and do it yourself.
Unfortunately, the typical acidity of a toilet bowl cleaner is usually too high to be handled by a consumer kit. It won't hurt you to get one (after all, you will be needing it in the future for other minor damages), but be prepared that if it won't work you will have to hire a bona fide stone restoration contractor that will have to slightly re-grind (hone) the damaged area of your top, and then re-polish it to blend with the rest.
May I ask you now to please read and e-sign our Statement of Purpose at:
http://www.marblecleaning.org/purpose.htm?
J
Ciao and good luck,
Mauri
Article ID: 315
Created On: Sat, Aug 11, 2007 at 12:55 PM
Last Updated On: Sat, Aug 11, 2007 at 12:00 AM
Authored by: Maurizio Bertoli [mail@mbstone.com]
Online URL: https://marblecleaning.org/knowledgebase/article.php?id=315