Yes, that is a cement tile. You can find several companies online who sell these tiles. They come in lots of amazing patterns and colors. I highly recommend them for a 'Wow' factor in your sunroom. We have radiant heat underneath the tiles which we love and the plants love too.

Thanks so much for the quick response! Again, you have created a beautiful space, and I hope it's treating you brilliantly this time of year! All best!