Dear Wendy:
Not much can be done, really. The acidity of the glue of the tape may have made a permanent etch-mark on your stone.
Try this: first you make sure to remove every residue of the glue by cleaning those lines with a clean white rag soaked with acetone (available at any paint store). Once we're sure that there's no glue anymore, if the discoloration persists but (temporarily) “disappears” if you wet it, the application of a good quality stone color enhancer like MB-6 will give you the same “wet look” (only darker, not any shiner) permanently. You do understand that this treatment will not actually repair the surface damage that you may have, but it will at least hide it from sight.
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: 1583
Created On: Thu, Jul 24, 2008 at 10:17 AM
Last Updated On: Thu, Jul 24, 2008 at 12:00 AM
Authored by: Maurizio Bertoli [mail@mbstone.com]
Online URL: https://marblecleaning.org/knowledgebase/article.php?id=1583