Very unclear. It could be an epoxy or polished concrete...hard to tell from the photos.

Get a tile cleaning product from Bunnings. Will ensure that the integrity of the tile is not compromised. However, by the look of the stains it seems as though something has been used that was too abrasive, too acidic or that had bleach in it. I do not recommend to keep any product on for an extended period of time. 5 mins max application!

Though I don't know for certain, I think the cotton/linen shades are removable. I wasn't able to determine this by my searches. This could easily be confirmed by making an enquiry to supplier before purchase. Alternatively, a handmade one could be made removable by making shade slightly larger than frame and making ties.

Thank you Luke I can see posted photos and floor plans again, could someone look into why my 'LIKE" still isn't working, if I click on the word LIKE I just end up adding another like and not seeing who has liked a comment.