Sometimes this can happen in the tile manufacturing process, a faulty tile or two can rarely slip through our quality control process
If you find a tile with defects simply bring it back to the store you got it from and they will happily replace it for you. If you can check the side of the box for the printed batch number we can supply tiles that match the shade of your other tiles. We will also do a thorough check of our stocks from that batch to remove any others that may have slipped through on that days manufacture.
It is important all tiles are checked before being laid as once they are hung unfortunately no claim for a replacement tile can be made.
We suggest you ask your tiler to keep an eye out for imperfections when tiling and to keep any tiles they are not happy with aside.