Have client that has a french limestone she says is called Corton. It seems quite dense. some time ago they had large amounts of water migrating thru the slab and found the source and corrected it. it cause some spalling/staining on the inside  but only efflorescence on the outside. the outside tiles are honed and the inside are polished. could the fact that the inside tiles are polished cause the pores to be so close up to prevent the stone from beathing properly?
Thank you
Stephen Webb