Nero Marquina Black Quartz Countertops, the advantage of quartz stone is that it is durable. Although quartz stone is an artificial stone, its main material contains a lot of quartz stone, and its hardness is very considerable. Its hardness can generally reach above grade 7. It is much higher than the knives and other sharp tools in the kitchen, so using it as a countertop is very wear-resistant, not easy to scratch, and has a very long service life.