Perhaps it was my fault in not askig more about unglazed tiles but the quality of these tiles, as my contractor said were terrible.  You have to use a wet saw to cut them, which he said was a nightmare. As soon as they got wet they were all falling off the backing.  Many were not spaced evenly, which meant, he had to cut them out and try arranging them himself.  Installation took 4 times longer with this issue.  Afterwards, we went to clean it, and all the grout turned dark until totally dry, AND, everything shows on it, scuffs from shoes, etc.  My husband already wants to remove them, but we paid to much to install them.