Regarding the authenticity of the tiles I have a set of methods to see the specifications. The common specification of the living room floor tiles is 80cm*80cm. Generally speaking, unless the tiles are too big, there may be deviations in length and width. Otherwise, there will be no problem. Of course, if you are more cautious, you can take a tape measure ahead of time when you go to the building materials market, randomly measure a few pieces when selecting bricks, in order to seek insurance, or randomly pick a few bricks to see if there is obvious deviation in the mosaic effect, and the color difference.
Look at the details of the surface of the tile. The surface of the tile is polished and touched by hand to make it smooth and delicate. The middle of the brick surface is mixed with artificial nicks to imitate the marble pattern.