Fwiw, I just mixed faux-marble quartz (Lagoon) with a Carrera backsplash and at least in it's pre-grouted state, I'm really happy. It was hard for me to find a backsplash that worked well with the grey-ish tones of the Lagoon, mostly because my cabinets are painted taupe. Anything that "matched" the cabinets seemed too brownish for the counters. The Carrera blends the two perfectly. I think it also works because I wound up using a very small-scale herringbone pattern, so the patterns in the marble tiles are less pronounced. Fwiw, I don't see the calacutta tiles that the OP posted working with a greyish quartz that's similar to Lagoon, and I'd also be concerned about pattern overload with a subway tile. But having worried about the fake-next-to-real problem, I wanted to at least add my experience that it can be done. One of the prettiest kitchens on here, done by a pro, is GW user @kompy, who used a different marble subway with Lagoon counters, and it looks stunning.

@Sophie, The more I look at Pyrolave, the more I think you're right. @Everyone, btw, in case anyone's wondering, this is Roger Ailes' home in Florida.. http://www.townandcountrymag.com/leisure/real-estate/g9229692/roger-ailes-palm-beach-house/

@Beth H. - thank you for your comments. I don't think we want to have dark counter tops. The kitchen is open to our family room. The minimal wall space in the kitchen will be painted a light blue color, as will the walls in the family room. We were thinking about: a) white cabinets and island b) the Calacatta gold marble 3" x 6" tiles for the back splash c) light(ish) counter tops on the perimeter and island (perhaps with some grey coming through d) medium brown hardwood floors We thought about using walnut for the island surface, but decided against it due to maintenance issues. If we didn't want to have dark counter tops, are there any other options? Thanks!

See if you can run a steak knife between the bottom of the stone and the sink flange. If so, your sink is leaking and trapping water there. The stone is sucking up the trapped water. The solution would be to drop the sink, let it dry completely, #40 peroxide (beauty supply store) the crack, superglue the crack with the runny stuff, seal the stone bottom, silicone the sink flange and strap it in place, then seal the top.