We have been selling Carrara marble for over 20 years for residential and commercial projects; including bathrooms, spas, etc.. and we have never once had an issue. Now, having said that, there are a lot of "scientific" variables that can play into the causes of chemical reaction in natural stones (ph level of water, chemical/mineral consistency of the stone, chemical treatment of the stone (acid washes, tumbling, brushing), UV exposure, temperature, traffic, etc...) Please note that I am only referring to true Italian Bianco Carrara from Italy. There are a lot stones that marble distributors/showrooms call "Carrara", but its not from Italy. Therefore, it is very possible that those stones have different compositions making them more succeptible to a chemical reaction. Plus if hundreds of statues and monuments in Rome that are made of Statuario, Carrara and Calacatta can withstand thousand of years of outside weather without orange stains, Im pretty sure it can hold up in a bathroom ;)
Q
Sample: Eleganza Calacatta Magnum Smooth
Q