It looked like marble to me, but I think it would be virtually impossible to get that large of a slab cut and you certainly wouldn't be able to get it into the apartment in one piece, either. Same thing with wood. No way you could cut one piece that large and get it into the building in one piece, unless it was installed as the building was being built then they finished building around it. But a sequoia is about the only tree that could possibly produce a piece of wood that large. My guess is it was faux painted for the film. If so, someone did a magnificent job. That would be a piece of art, in itself!
Probably a faux painted finish for the movie, but you could get a permanent look with a concrete floor, acid stain and lots of high gloss sealant. And a skilled artisan!
The wood floor caught my eye as well. The house was authentic and probably the floor was as well. That wood design I can't recall the name. But it does exist, is very expensive, and originates in the Far East.