Hi Josh,

For your Diana Royal marble pavers, using white Type S masonry cement with white sand is a good choice. Wash the surface before applying the Catalina sealer to ensure a clean finish. It's also a great idea to apply a waterproofing sealer over the concrete base to prevent moisture or rust from the rebar.

For detailed installation guidelines, I recommend checking with the Marble Institute of America or Tile Council of North America for best practices.

If you need professional help with your project, you can contact me through my Houzz profile.