Thanks ...
I keep thinking of Cemetary headstones. Birdpoop is acidic, and Lord knows that they shine back up every rainstorm.
Hard to believe that masking tape would do anything at all to stone.
The degree of acidity may differ.
Cemetery headstones are usually made of concrete or granite. I haven’t see a whole lot of marble. Marble is better suited for interior use.
They are made of granite,one of the hardest rocks on earth. They don't stain. Go to an old cemetary the old marble headstones are so rough the are hard to read.