Dear Mrs. Grover:
I assume that the “stains” you're making reference to are dull spot and look like water-marks. Red Bull, like any other pop soda drink contains phosphoric acid, and it etched (corroded) the surface of your stone on contact. Of course, no sealer for stone could even begin to prevent such type of surface damage from happening, which has nothing to do with the (very low) absorbency rate (a.k.a. porosity) of your marble, but exclusively with its chemical make-up (calcite).
A consumer-friendly marble polishing powder like MB-11 should enable you to repair the damage.
May I ask you now to please read and e-sign our Statement of Purpose at:
http://www.marblecleaning.org/purpose.htm?
Ciao and good luck,
Mauri
Article ID: 688
Created On: Fri, Oct 26, 2007 at 10:48 AM
Last Updated On: Fri, Oct 26, 2007 at 12:00 AM
Authored by: Maurizio Bertoli [mail@mbstone.com]
Online URL: https://marblecleaning.org/knowledgebase/article.php?id=688