Quartzite is harder than granite. Marble is softer and can etch. Taj Mahal is currently a popular quartzite that can be used as a slab backsplash for increased affect.

The counter has a leathered finish. There are different tones ad grades of Taj. And there are other quartzites. You have to test them.

I am a fabricator. Marble is only a little harder than jello and slightly less absorbent than a sponge. Great for statues, not so much for a work surface. True quartzite is the opposite; harder than most countertop options and not particularly porous.