Just by the name of the stone one can become intrigued. It sounds like it is related to or the same thing as the mineral quartz. Upon looking at the stone though it has an appearance resembling that of marble. Natural quartzite is a stone that has much to offer. In this article we will explore the basic information about natural quartzite. As we do, we will look at why people choose quartzite and what its properties are. We will also look at what is involved with fabricating it and how it needs to be cared for and maintained.
Why People Choose Quartzite
People choose natural quartzite because of its visual appeal. The stone is often available in neutral shades of color that coordinate well with various design styles, textures and color palettes. Another reason quartzite is often selected is because it is durable. Especially when used in the home, the durability of a surface material is an important factor in the decision of whether to go with it as a material for a surface.
Properties of Quartzite
The appealing qualities for which quartzite is desired stem from its properties. And the properties of a material are a direct result of it composition. Let's look at some of the properties of natural quartzite and see how the composition of the material plays a role.
Durability from Hardness
The durability mentioned previously is a result of the stone's hardness. Surfaces are made of various materials whose hardness is measurable. The Mohs scale of mineral hardness is a scale ranging from 1 to 10 and each surface material carries a hardness value found on that scale. Quartzite registers on the high end of the scale. Below we have a Mohs scale showing where quartzite is found, marked by a plus.
Mohs Scale of Mineral Hardness
Talc is a mineral that is the primary part of talcum powder.
Formed when seawater evaporates from the surface of the Earth. It is also found in drywall.
A carbonate mineral found in many popular stones such as marble and limestone. It is often the primary constituent of the shells of marine organisms.
The mineral form of calcium fluoride. It is often used for ornamental carvings.
A group of phosphate minerals named by the German geologist Abraham Gottlob Werner.
Feldspars are a group of rock-forming tectosilicate minerals that make up about 41% of the Earth's continental crust by weight.
A hard, crystalline mineral composed of silicon and oxygen atoms which belongs to the trigonal crystal system.
Topaz is a silicate mineral of aluminum and fluorine. In its natural state, Topaz is golden brown to yellow in color.
Corundum occurs as a mineral in mica schist, gneiss, and some marbles in metamorphic terranes.
Diamond is a solid form of the element carbon with its atoms arranged in a crystal structure called diamond cubic.
As you can see from the table above, quartzite is a 7 on the Mohs scale. The 7 place in the scale is measured by the mineral quartz. See the correlation? That's right, they are related very closely. Natural quartzite is, in fact, composed largely of the mineral quartz. Thus, the hardness of the stone is the same as the hardness of the mineral.
Appearance from Crystals
One of the things that gives quartzite its distinct look is its crystalline composition. Notice what a geologist noted in an article published by usenaturastone.org regarding the make up of some quartzite:
To help make these 'shades of quartzite' easier to understand, we can break down the sandstone-quartzite continuum into 5 categories. These range from porous sandstones, which are only loosely bound together, all the way to crystalline quartzite, which got so hot it nearly melted. Then there's what I'll call "mixed stone" quartzites, which are on the borderline between quartzite and other metamorphic rocks like schist and gneiss. These stones contain some quartzite, along with other minerals and rock types. In general mixed stone quartzites are darker in color than regular quartzites, and they have swirls and blobs of different rock types blended together. The table below outlines the 5 types of sandstone and quartzite.
Perhaps the reason quartzite is so desirable is because it has a crystalline composition. Think a moment about marble. Marble too has mineral content that is in the form of crystals. In fact, marble slabs sometimes get labeled as quartzite even though they are not quartzite. Marble is very elegant and desired material in upscale applications. Yet, it is a bit vulnerable to acidic substances. Quartzite though, although it resembles marble, it does not have the same vulnerability to acid that marble has. SO it is no wonder that like marble, quartzite is a sought after natural stone.
As with every material there are a variety of uses in which quartzite performs nicely. Many of these are hard surfaces in building projects. Here is a list of some of the applications of natural quartzite:
As you can see from the list above, quartzite is a very versatile material and is used for many surfaces indoors and out.
As you might imagine, fabricating with natural quartzite requires not only skill and experience, but also specific tools and equipment. We have already talked about the hardness of natural quartzite, so we won't get into that here. But the hardness of the material means specific blades, bits, and polishing tools are needed. For example, there are many diamond blades on the market but not all of them qualify to be a good blade for cutting quartzite. The blade's matrix and the diamonds must be specifically matched in order to effectively cut material that is as hard as natural quartzite.
Core bits also must be of the proper material in order to make their way through stone that is as hard as quartzite. Finding a core bit for quartzite is another task that is well worth the effort.
In addition to tooling it is also important that fabrication shops have a carefully selected supply of quartzite polishing pads so that the surfaces can be worked to a nice attractive finish.
Quartzite Care and Maintenance
Natural stone is often times (in fact, nearly always) porous. This means it needs to be cared for in a way that allows for this feature of the material. For example, water based and oil based liquids that penetrate the pores of the stone can discolor it; leaving a stain that requires removal. Thus, a routine that takes into consideration the stones porosity is important. One care and maintenance routine that many use is this four part maintenance routine:
Apply an impregnating sealer to the stone's surface so that the rate of absorption is inhibited. This application will need to be done periodically. Testing the stone's absorption rate is an effective way to determine if it is time for anohter application of sealer.
If a stain occurs on the stone, use the appropriate stain remover for the type of stain. Oil and Water based stains can be removed using a poultice powder.
Some quartzite owners prefer to use a fortified stone polish regularly to add a layer of protection to the surface of the quartzite. Doing this in addition to using the appropriate cleaner will increase the time between sealer applications.
In the end, quartzite is a natural stone that has a number of outstanding traits that many consumers desire in a natural stone. The hardness, color selection, and elegance coupled with the durability make it an effective substance from which to make household surfaces. Yet, if you choose to work with quartzite it is good to have an idea of which products you will need to have on hand or in the truck.