Hi Claire Lavie,
Thank you for your questions. There is a number of substrates that are suitable for this product. Please go to this product page and scroll to the bottom and look under the section titled, "Installation, Videos & MSDS". There you will find a complete set of specifications and instructions. As for the mother of pearl tile, if it''s transparent it may show through. Please check the specifications document as well.
Thank you,
The Koffler
Team