Stains happen when some substance, food, drink, product absorbs into the marble pores and is always darker in color.
The "cloudy" spot that you describe is etching and is due to corrosion caused by the highly acidic Lime-Away product.
Marble is reactive with acids and will etch upon contact.
It's like a chemical burn that has destroyed the surface layer exposing more raw and lighter colored marble underneath.
It's important to know though that a substance can etch and then stain if it absorbs, so you can have two completely different problems in the same spot. If it did stain, it would be a dark, dull spot instead of a light, dull spot when it's only etching.
So, use the paste unless your marble is honed....
If your marble is honed (matte, non-shiny finish) then the paste won't work and you'll need to follow the instructions provided by the Removing Etch Marks ebook guide.
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