Quartzite
Quartzite countertops: how to choose the slab, from Taj Mahal to Cristallo.
Quartzite is the stone most people ask for when they want the look of marble in a kitchen that gets cooked in. Taj Mahal is the name we hear first. Cristallo is close behind. Both are in our racks at 97 Airport Road, along with Audacia, Bellaggio, Belvedere, Infinity Blue, Infinity White and more. Our quartzite page shows the slabs that are in right now.
This piece is about choosing the slab once you have settled on quartzite. If you are still weighing materials, read quartzite or granite for cost and care. If the names are getting mixed up, read quartz or quartzite first.
What makes a stone quartzite?
Quartzite starts as quartz-rich sandstone. Heat and pressure deep in the Earth recrystallize the sand grains and the natural cement between them. Hobart King of Geology.com describes the result as a network of interlocking quartz grains. The U.S. Geological Survey lists quartzite with marble among the common metamorphic rocks.
Because it is almost all quartz, quartzite rates about 7 on the Mohs hardness scale. That is harder than glass and harder than a knife blade. Kitchen acids like lemon juice and vinegar do not etch it. Those two facts are why people want it. They are also how you check a slab.
Why is the name on the tag not enough?
Quartzite names are trade names. They are not test results. Karin Kirk, a geologist writing for Use Natural Stone, the Natural Stone Institute's consumer site, puts it plainly. Quartzite itself has very consistent properties. The labeling is what varies. Some stones sold as quartzite are marble or dolomitic marble. They can look the same in the rack and behave very differently in a kitchen. They etch from acid and scratch more easily.
Kirk also says there is no such thing as "soft quartzite." A stone sold under that label is most likely marble. She adds that country of origin, price and the name of a stone are not reliable signs of what it is. Her one named example is Super White, which she says is most commonly dolomitic marble.
None of that makes a slab good or bad. Marble is a fine stone in the right room, as our piece on marble in a working kitchen explains. It just means a kitchen planned around quartzite should get a stone that behaves like quartzite. The way to know is a test, not a name.
Which tests should you ask for?
Use Natural Stone describes three simple checks. Each one is done on a sample or an offcut of the stone, not on the face of the slab you are buying. Ask for them before you commit.
- The glass test. Press a rough edge or point of the stone hard across a glass tile. Real quartzite bites into the glass and leaves an obvious scratch. A faint line, or a powdery trail that rubs right off, means the stone is not quartzite. If the stone has more than one color or mineral in it, test more than one spot.
- The knife test. Where there is no rough edge to use, try to scratch the sample with the tip of a knife. Quartzite is scratched lightly or not at all. Marble and dolomitic marble scratch easily.
- The etch test. Put lemon juice or vinegar on the polished surface, leave it about 15 minutes and wipe it off. Marble shows an obvious dull, lighter or darker spot. Dolomitic marble shows a fainter one. Quartzite shows nothing.
One limit is worth knowing. The Natural Stone Institute warns that many rust removers and some toilet bowl cleaners contain traces of hydrofluoric acid, which attacks every stone, granite and quartzite included. The etch test is about the acids you cook with. Keep those cleaners off the counter whatever the stone.
What do Taj Mahal and Cristallo tell you?
Taj Mahal is the slab most people arrive asking for. It is a warm cream with soft movement. We import it directly and generally keep it in 2cm and 3cm polished. Our quartzite page shows a 2cm slab at 120 by 78 inches. Kirk names Taj Mahal as a highly metamorphosed quartzite with tightly bonded minerals. In her water test, a Taj Mahal sample did not even look wet.
You can see a finished Taj Mahal kitchen on our quartzite page. The perimeter counters, the island and the backsplash behind the range are all the same stone, which is how the cream and soft gray read as one room.
Cristallo looks very different. The slabs in our racks are white and pale gray with a glassy, crystal look and a few thin gold lines. Our page lists a polished 2cm Cristallo at 138 by 75 inches, plus 3cm stock, and a finished Cristallo island in the installed work. That glassy surface is what Kirk describes in a fully crystalline quartzite: no visible sand grains at all.
Here is the lesson from both. A name tells you roughly what a variety can look like. It does not show you the slab you will get. Use Natural Stone notes that slabs cut from one block are usually numbered so you can buy the neighbors. If your kitchen takes 2 slabs, ask for neighbors from the same bundle and look at them side by side.
How porous is the slab?
Quartzite is hard, but it is not all equally dense. Kirk describes a range from grainy, more porous quartzites to fully crystalline ones. Taj Mahal sits at the dense end. She names White Macaubas and Calacatta Macaubas as more porous stones that benefit from sealing.
Her check is simple. Stand one edge of an unsealed piece in water for about 15 minutes. If the water wicks up above the waterline, the stone is porous. A porous quartzite is still a good countertop. It needs a proper seal on the cut edges as well as the top, and a reseal from time to time.
We seal every natural stone before installation. The Natural Stone Institute says a sealed stone is more resistant to everyday dirt and spills. It is stain resistant, not stain proof. What sealing buys you is time to wipe up the oil or wine. At home, use the check we give every customer: leave a few drops of water on the counter for 10 minutes. If the stone darkens under them, it is time to reseal. If it does not, leave it alone.
Polished or leathered?
Our quartzite comes polished or leathered, depending on the slab. Use Natural Stone describes a polished finish as glossy and reflective, one that enriches the look of the stone and is easy to keep up. Leathered is brushed to a soft, bumpy texture with deeper color. It resists fingerprints and smudges well. The small pits take a little more effort to clean.
The same stone can look quite different in each. If the variety you like comes both ways, ask to see the two finishes side by side before you decide.
Will one slab cover your island?
Slab size decides seams. A run longer than the slab needs one. Here is how that plays out with two slabs from our page. Say your island top is 126 inches long and 48 inches deep, overhang included. It cannot come out of the 120 by 78 inch Taj Mahal in one piece. It can fit on the 138 by 75 inch Cristallo. Every slab is a different size, so we check the fit against the real slab you tag before anyone cuts.
Veining matters as much as size. People buy quartzite for its movement, so a quartzite job often uses more of each slab to make the pattern flow across an island or meet cleanly at a seam. Decide where the seam falls and which way the veins run while you are standing at the slab. Our fabrication process piece covers the seam rules.
What should you bring to the yard?
- Your measurements. The longest run and the island, overhang included. They tell us how many slabs you need.
- A cabinet door or a paint chip. Cream Taj Mahal and gray Cristallo look very different next to white paint or stained wood.
- Your questions. How many slabs are left in the bundle, which finishes the variety comes in, and whether a sample can be tested.
People come to Airport Road for quartzite from across the state. We work in West Hartford, Rocky Hill, Glastonbury and Avon, and as far as New Haven. The yard is open weekdays 8:30 to 4:30 and Saturday 9 to 1. Come stand in front of a full slab, or tell us about the kitchen and we will get back to you within one business day.