Hi Bill, these are basalt tiles, we specified them for the project and sourced them directly from the supplier. This was almost ten years ago now so I am afraid I don't have the information directly to hand. Good luck with your project, I am sure that you or your architect/designer can find something similar by searching using 'basalt strips' as your search input. Slate strips from Mandarin Stone could be considered as an alternative; though do your research regarding substrate, adhesive, grout etc.