Quartzite is a natural stone that gets confused with now trending stone Quartz, and I will explain the differences here.
Quartzite has become an increasingly popular countertop option, It has a similar look to marble but it’s more robust and doesn’t have the staining and etching issues that marble can have, there is a lot of confusion in the natural stone industry about quartzite it is because marble and dolomitic marbles (dolomites) are often mislabeled as Quartz Sites. In many cases it is nearly impossible to tell a marble and quartzite apart, simple diagnostic tests are the only way to tell the difference between the two stones.
There is no such thing as a ”soft quartzite”
Quartzite is a very specific countertop material, and it is always hard and will not etch, it is a metamorphic rock, made almost entirely of the mineral quartz, begins its geologic life as sand, which then becomes sandstone. As it get buried, it experiences heat and
compression, eventually loosing its shape and becoming a dense durable rock.
Quartzite is usually white or light color, because quartz sand is light colored. Additional minerals carried by water can impart additional hues such as blues and greens.
Because quartzite is made primarily of quartz, the hardness and acid resistance of quartzite is different from the minerals in marble. It is important to understand that Quartz mineral is different from the manufactured countertop materials referred as QUARTZ, which contain quartz minerals bonded together with resins and pigments.
Quartzite is hard and durable, it is number 7 most hardness on scale. It is nearly twice as hard as glass and harder than a knife blade. Also resistant to acids,
Etching is very common with marbles and small areas on the surfaces dissolve creating dull spots. While etching doesn’t harm the stone, it does cause dull blemishes, eyesores to the eye. Quartzite doesn’t etch with normal kitchen acids such as lemon juice or vinegar.
Line any natural stone quartzites are porous, some quartzites like taj Mahal and seapearl have been highly metamorphose and the minerals are tightly bonded. Other colors like white macaubus are more porous and benefit from sealing.