I
Italy
Think sameThey look like a low grade Carrara Marble (low simply meaning they are more grey than white) used to create a mosaic.
If they have been recently laid (last day or so) they may still be retaining moisture from the grout/adhesive which gives them a darker appearance (grubby looking almost).
If a dark adhesive has been used rather than a white adhesive that will also darken the marble.
If they've been sealed, they may have been sealed too soon, locking in moisture and darkening the stone.
If you look at the edge of each hexagon, they are sawn and the edges aren't eased or finished in any way so you can see chipping along all six edges of the hexagon. This is highlighted once it's grouted. They don't look well manufactured to be honest.
How long ago was the job completed?