Quartzite is a metamorphic rock that originated as quartz-based sandstone. Through a process of high heating and pressurization, sandstone is transformed into quartzite. Pure quartzite countertops are typically a white or gray shade. The presence of additional minerals can impart hues of vivid colors like green, blue, or red. On the Mohs Scale of Hardness, pure quartzite has been given a hardness reading of 7 out of 10 (10 being the hardest) – harder than granite! If you are looking for the aesthetic quality of marble, quartzites are a viable option to consider. They are a much harder material than marble, which decreases their susceptibility to damages from regular wear and tear that medium to heavily used kitchens and bathrooms normally see.