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Quartzite

A rock formed from the metamorphism of quartz sandstone.

Sandstone that has been converted into a solid quartz rock. Quartzites are usually white; they fracture smoothly and break up into rubble under frost action. Sandstone may be converted to quartzite by precipitation of silica from waters below the Earth's surface; such rocks are called orthoquartzites, whereas those produced by recrystallization (metamorphism) are metaquartzites. Because they weather slowly, they tend to project as hills or mountain masses. Many prominent ridges in the Appalachian Mountains are composed of quartzite. Pure quartzites are a source of silica for metallurgical purposes and for the manufacture of silica brick. Quartzite is also quarried for paving and roofing materials.

Material Notes:
Metamorphic rock with the critical mineral quartz (up to100%) and mica. It is formed from the sedimentary rocks quartz-sandstone or conglomerate.

Typically quartzite is obtained by surface mining, since most deposits are either exposed or located near the surface. The stone is extracted by first removing any overburden from above the stone and it is then removed using large excavators.

At times, explosives may be required to loosen the stone ledges. The detonation only bumps the stone away from the natural ledge, this way the stone mass is loosened, not blown into small pieces.

Drilling, feathers and wedges for plugging are used for breaking larger blocks into thin slabs. Miners will tap each wedge and continue down the stone until it begins to separate. Then the feathers and wedges are removed and a pry bar is used to finish separating the slab from the rest of the stone.

Once removed from the quarry, the stone is split manually using a labor intensive method of spliting the stone by hand using hammers and chisels resulting in a rustic looking natural stone with a beautiful looking naturally rough finish. Because of quartzite's hardness and mica content, it makes it difficult to cut into calibrated thickness's.

Quartzite is starting to gain popularity around the world in the landscaping and building industry and its beautiful metallic and quartz appearance has been used in some of the most extravagant homes around the world. Quartzite may not be as well known as other stones used in the landscaping and building industry such as granites, marbles, sandstones and limestones but its unique characteristics,hardness, durability and its clean fine-grained texture will make it the stone of choice for many challenging projects that require a different aesthetic appeal.

Quartzite is composed of sandstone that has been metamorphosed. Quartzite is much harder than the parent rock, sandstone. It forms from sandstone that has come into contact with deeply buried magmas. Quartzite looks similar to its parent rock. The best way to tell quartzite from sandstone is to break the rocks. Sandstone will shatter into many individual grains of sand while quartzite will break across the grains.

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