This is black slate. It was one of the cost-savings measures on this house and ended up looking really striking against the natural wood. Good luck with your project!

Thanks so much! I'm going to look into this. It's exactly what we've been looking for.

What company makes the black slate tile?. Is it natural or porcelain? Where can I purchase the black slate floor?

Those are Brazilian Black ( Montauk Black ) Cleft Slate Tile 12"x24".

They are available at MarbleWarehouse.com.