Contact your tile installer. All tile needs to be sealed. The sealer protects the grout and needs to be re sealed annually.

Tina - I wanted to let you know how lovely this bathroom design is. It practically takes my breath away. Well done;)

Your bathroom is Beautiful! This is what I found out about cleaning marble.
Dry with a towel after each use. Sweep a few times a week for any dirt. Anything loose dirt can scratch the tiles. Once a week clean with a neutral PH (retail stores) cleaner, follow instructions. About every 4 months , seal & then polish to a shine. Sealing helps with staining. Good luck,

joancuneo, thanks for the comment. I don't believe it is necessary to go to that extreme as I have designed many bathrooms and kitchens with marble If your bathroom is cleaned weekly and you are careful not to spill make-up or other staining elements on the floor, then a good scrubbing with a non-abrasive cleaners is all that is takes. Most of my clients have weekly or twice a month cleaning services and their marble has been just fine.

LOL. Tina I agree. I would not go to that extreme for my marble. This is what the marble companies tell you. If I had a new bathroom I might do it for 2 weeks. The bathroom is beautiful, I don't want anything to happen. It should be sealed at least 2x a year, if used often.