Looks a lot like the Refin Forum series (porcelain with the look of stone) tiles that I just used in my shower remodel. Maybe, maybe not what was actually used here.

This is a porcelain tile purchased at Olympia Tile in Toronto. It is from over 5 years ago so probabbly no longer available though.

Do you know what color the tile is or was?

Marble Granite Depot has it too in travertine

You can find these tiles on floridatile.com website. It's the Renaissance Tile...Color Grigio.