Kat Coleman, owner and principal of Long Beach, California-based Topkat Design Group, had a client who loved Carrara marble and wanted her entire bathroom to feature natural stone: main bathroom floor, shower floors, and walls with a decorative feature wall behind a claw-foot tub. “We are talking Ritz-Carlton style,” Coleman says.

Carrara marble. Photo courtesy of Kat Coleman, Topkat Design Group.

Coleman’s client was concerned the natural stone would be too high maintenance and possibly cost prohibitive. To try to meet her client’s aesthetic, Coleman searched for alternatives, but they were unsatisfied since those options just didn’t look or feel like the real thing.

The reality is genuine natural stone, like Carrara marble, cannot be mimicked. Coleman knew it was her job to educate her client and remind her that marble has been used for centuries. Many commercial settings use marble throughout high-traffic areas and hotel bathrooms successfully, and the sealers on the market have improved substantially over the last decade. She convinced her client that Carrara marble was the best choice for her bathroom.

“This was close to 10 years ago and her bathroom still looks like new,” Coleman adds.

Sealers and Grout for Natural Stone

Whether going for a polished, honed, or leathered finish, choosing the proper sealer and maintaining the sealing process is probably the most important thing clients need to consider when using natural stone in their spaces, according to Coleman.

“Some softer stones such as marble are more prone to possibly show wear over time, although I have a few past clients who have all-Carrara marble bathrooms that still look pristine after many years,” she says.

One trend she’s noticing is that clients seem to want as thin a grout line as possible. Selecting a stone with a straight edge versus a slight bevel is best to achieve this. She reminds clients that stone is a natural material so there needs be some tolerance. What some clients may view as imperfections in natural stone, Coleman calls “character.” “Nature is perfectly imperfect,” she reminds clients.

Fresh and New Natural Stone Finish Trends

Coleman finds that most clients still think a polished finish is their only option. It’s often their designers, who are well-versed in what’s happening in their industry and what’s available, who turn them on to other options or educate them on what they may actually be looking at when they present inspirational images.

Premium Absolute Black granite with natural finish. Photo courtesy of Kat Coleman, Topkat Design Group.

She admits polished countertops are the norm in the United States, but matte-type surfaces seem to be having a moment in the natural stone space right now. “I have the occasional client mention a desire for a honed (or leathered/suede) countertop but usually it’s me, as the designer, making the recommendation in the design,” she says.

Manufacturers are constantly creating new options in finishes, which is exciting for Coleman and her clients. She’s recently learned of a brushed countertop surface finish. “This surface has a matte look with a brushed texture,” she explains. While she’s not yet had the chance to install this finish in one of her projects, she admits she’s intrigued and looking forward to doing more research to learn the pros and cons of using it in one of her designs.

A finish she does love to use for kitchen countertops is honed. Honed is the original matte-type surface. In bathrooms, she enjoys mixing honed and polished stone. For example, she’s combined honed floors and niches in a shower with polished stone walls.

Leathered finish on stone has been around for some time and Coleman says it has a sexy but classic look and feel that men seem to like.

Updating Natural Stone Countertops

For those who want to refresh or update spaces like a kitchen and keep their existing cabinetry, one option is having them restored to a different finish. “A perfect example would be if you had the popular polished black granite countertops that were all the rage around the early 2000s,” says Coleman. “You can have a fabricator put a honed finish on these, replace the backsplash, and you would have a completely different and more current look!”

Choosing Natural Stone for Its Beauty, Strength, and Longevity

There are many reasons why clients choose natural stone for their projects and there is something to be said about the beauty of the real material versus something that looks like stone. Coleman knew her client from 10 years ago wanted marble and while she could have settled for a non-marble look-alike, the reality is she wouldn’t have been happy. Instead, advising her client on how to care for her marble means her client was able to include the stone she wanted in her bathroom and is still happy a decade later. Nothing beats the real thing.

Polished White Macaubus quartzite. Photo courtesy of Kat Coleman, Topkat Design Group.

While marble remains a favorite among her clients, Coleman has been installing more quartzite lately. She appreciates that quartzite is harder than granite and can sometimes even be non-porous, although she highly recommends testing the porosity level if that feature is important to a client. White quartzites have the look of marble with the durability of granite, she says, which makes them attractive to clients.

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Photos provided by Jan Neiges CMBKD; Photographed by: Virtuance.

Jan Neiges is a certified master kitchen and bath designer with the National Kitchen & Bath Association and principal of Colorado-based Jan Neiges CKD LLC. She has been helping her clients define and realize their visions for beautiful and functional high-use living spaces for over two decades. Neiges sees natural stone as a go-to material because “every piece is unique, especially if one selects the stones that have more colors, movements, and patterns.”

A client recently asked for a white-on-white-on-white kitchen but knew they needed some color in the space. Neiges encouraged her client to explore different natural stone showrooms to see if something might appeal to her and she fell in love with a white quartzite with gold veining for the island countertop.

“The island countertop is the pièce de résistance,” Neiges says. “It’s such a large island and because everything was somewhat sterile and flat in shape, except for the island which is curved, I suggested that we go with something very fluid for the light fixtures hanging over the island.”

Neiges suggested a gold-tone faucet for the island to help accentuate the gold in the quartzite.  The result is a stunning white kitchen where the natural stone plays a starring role.

For Neiges, the act of discovery and finding out what is drawing the client to a particular piece of natural stone is part of the fun when working on a kitchen with a client.

Choosing Natural Stone for a Kitchen

Neiges often recommends clients visit showrooms with their designers because “there’s more to it than just pointing your finger and saying, ‘I like that’ when it comes to natural stone.”

Showrooms allow clients to see what’s available and possible. In the Denver area, Neiges recommends her clients visit one of the three major showrooms and prepares them in advance by telling them it’s like walking into Tiffany’s. It’s an exciting part of the process and one that opens up the possibilities of finding natural stone they might not have considered or seen before in other places or in magazine spreads.

Most natural stone showrooms have a template available to show the depth of a countertop dimension. “It could be five or six feet long and 26 inches wide and it could be made out of some kind of plastic or metal,” Neiges explains.

They then take the template and walk around with it, placing it in front of natural stone slab options so clients can see patterns, movement and how it might look next to other design elements they’ve selected such as the finish of a cabinet or paint color.

She’ll ask them questions to find out what they are seeing and what is standing out for them. Once they’ve found the stone they love, they’ll discuss any questions they might have about caring for the stone.

When someone wants natural stone, Neiges says, they’re usually looking for stone to be that “wow element” in their space. She tries to find the right natural stone based on how the family or homeowner will use it. “If this [stone] is really something that turns you on, and you really want to see it a lot, let’s find a vertical application for it,” suggests Neiges. Since vertical elements are the first things we see when we walk into a space, why not use natural stone there?

One homeowner wanted something spectacular for the wall behind their cooktop. They decided to make that area the focal point of the space—“Grand Central Station” of the kitchen. As a result, they were intentional with the rest of the kitchen design, choosing more subdued elements until they found the piece they were looking for.

The homeowner fell in love with Tempest Blue granite with a leathered finish from The Stone Collection, an “amazing granite with wild colors,” according to Neiges. They decided to use the stone both in the space above the cooktop and for the countertop itself. The busiest section of the slab was chosen for the area behind the cooktop because it would allow for easy cleanup (no grout) and would be fascinating to look at while they are cooking. They can now see and enjoy the beauty of the natural stone as soon as they walk into their kitchen.

When to Remodel vs. When to Refresh a Kitchen

Neiges works with many clients who are remodeling their entire kitchen. Her recommendation on whether to remodel or refresh a space by making minor changes differ based on a client’s short and long-term plans.

“If they’re going to live in their house for some time and they can’t stand their countertops and want to replace them with a natural stone and they know they’re likely going to remodel their kitchen at some point, I encourage them to wait to replace the countertop because it’s like putting lipstick on a pig,” she advises.

Part of the reason, she says, is because the stone will look gorgeous but the rest of the kitchen will look dated and when they go back to remodel the kitchen a few years later and the countertop may not fit the new cabinetry, the client will be upset because they’ll need to figure a work around and it won’t look the same.

“My attitude is to do your project from A to Z, don’t piecemeal it,” she recommends.

The only time she recommends replacing just the countertop or other minor spaces like a backsplash area is if the homeowner plans to sell within a year. Otherwise, “just save your money and wait,” she advises, and enjoy the process of finding things that will make your kitchen functional, enjoyable, and fun.

TAGS: trends design megy karydes inspire

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Note: This article is part of a series about American quarries. If you work for a quarry that’s a member of the Natural Stone Institute and you’d like your quarry to be featured here, contact Karin Kirk. Thank you!

In 1952, Gary Mullard loaded a pile of quartzite into his pickup truck, drove down from the mountainside and into the nearby town of Oakley, Idaho, and declared the boulders for sale.

At the time, in a rural agricultural area with few nearby markets, it seemed doubtful the idea could succeed.

But this quartzite had qualities unmatched by other stones, and steadily it gained ground as a viable product. By the 1980s, Rocky Mountain Quartzite was fetching twice the price of other stones, and it was sold in 20 states and Canada. Dubbed “Oakley Stone,” the sparkling quartzite became a significant source of income to the region, and several quarries opened in the area. Today, Northern Stone Supply ships 50,000 tons of quartzite and granite to distributors across the U.S. and into Canada, infusing the local economy with $80 to $90 million of economic activity annually.

The story of Rocky Mountain Quartzite is a classic American success story that brings together all the necessary elements: favorable geology, a product that could distinguish itself from others, and a business plan and workforce that could develop the company to its full potential.

Natural layers are thin and strong

Quartzite is one of the most popular and in-demand stones today. But way before quartzite was a darling of the stone industry, this particular quartzite was recognized for traits that make it especially useful. Most of us already know that quartzite is a strong, durable rock, but Rocky Mountain Quartzite is more than that. Its white quartz layers are interspersed with bands of glittery mica, and the stone cleaves along the mica planes, resulting in a useful, yet natural shape. Better still, the mica minerals add an ethereal beauty to the stone, imparting a silver or gold shimmer to the surface of the slabs.

The combination of strength and thin layering is the winning formula for Rocky Mountain Quartzite. With most stones, thin layers tend to be weak. But the recrystallized quartz crystals are fused together solidly, such that slabs less than an inch thick are plenty strong enough to use as patios, walkways, or building stone. Typically, stones need to be at least 2 inches thick to withstand those uses.

Thus, for a given weight of stone, Rocky Mountain Quartzite can cover twice as much area. This reduces shipping cost and simplifies projects. It makes the stone usable as a veneer and appeals to DIYers who needn’t perform feats of strength to build a garden path.

The recipe of strength, versatility, and local provenance has garnered Rocky Mountain Quartzite a devoted following. This beautiful quartzite has become a popular building stone in the mountain west, and throughout the United States and Canada. Northern Stone Supply ships about 25,000 to 30,000 tons of finished quartzite every year.

A buried beach re-emerges

The story of Rocky Mountain Quartzite begins as beach sand around 600 million years ago. Grains of quartz sand eroded off some of the planet’s oldest rocks and settled in a shallow ocean. After each layer of sand was laid down, a pulse of clay washed in, interrupting the white sand grains with a thin, dark blanket of sediment. On top of that, more sand grains flowed in. Then another wash of clay. That sequence repeated itself with remarkable regularity, as thousands of feet of sediment piled up.

The layer cake of sand and clay was eventually buried by miles of rock, fusing the sand grains into a dense sandstone. A series of tectonic collisions occurred along the west coast of North America as small landmasses, carried along the conveyor belt of the Pacific Ocean floor, got shoved into North America. Thus, the entire western portion of the U.S. was compressed. This event crumpled up the formerly flat-lying layers of rock and gave rise to the Rocky Mountains.

About 50 million years ago, the compression stopped and then about 17 million years ago, the tectonic motion ran in reverse, pulling and stretching the continent. The region around Nevada and southern Idaho was stretched apart to form “basin and range” topography. Remarkably, in some areas the land was pulled apart so much that it became twice as wide as it previously was. As the landscape was expanding, some areas sank downward, making valleys, while other segments of rock rotated and bobbed upward, forming mountain ranges. The stretching caused younger rock layers near the surface to be rifted apart and allowed “windows” through which deeper, older rocks were exposed.

Thus, a rock that had been buried for more half a billion years found its way to daylight again. After all that it had endured, the quartz sand grains were now welded solidly together in a dense, hard, crystalline stone. The clay layers that interrupted the sand had been transformed into sparkling mica.

Quarrying is an operation “completely dependent on hands”

A few more geologic coincidences helped this rock become straightforward to quarry. Thanks to the way the stone was uplifted, the quartzite is found right at the ground surface, so no excavation is needed to get to the stone. Secondly, the layers of the rock run parallel the surface of the landscape, meaning that individual seams can easily be followed. Because the rock is situated with convenient access, the operation can be low-tech. Even today, little equipment is needed at the quarry.

Blocks of rock are pulled out of the slope with excavators, then hand-split along the mica layers to create smooth, natural surfaces that look as if they’ve been dusted with glitter. “It’s an operation completely dependent on hands,” says Karla Forest, Marketing Director of Northern Stone Supply. Skilled quarriers “delicately work along seams,” as they follow the thin zones of mica. The split stones are then sorted by thickness and size and stacked in crates.

A drawing from a 1984 mineral patent application for Northern Stone Supply. The drawing depicts the simplicity of the quarrying, thanks to convenient geology that put the quartzite right at the surface.

Google Earth image of the quarries near Oakley, Idaho. This image is about a half mile across. Northern Stone Supply works 1300 acres of quarries in the area.

Gold, silver, white, and grey: A diverse set of products emerges from the quarry

The town of Oakley sits 8 miles north of the quarries. A steady flow of trucks brings stone down from the quarries, into the town of around 900 people. About half of the quarried stone is left in the natural shapes that are split by quarriers. The rest of the stone is fabricated into thin veneer, tiles, dimensional paving stones, and tumbled stone.

Idaho’s harsh winter weather means that quarrying is seasonal, running from April through October. In the winter, a smaller workforce fabricates the previous year’s harvest into various products.

Thanks to the diversity in the mica minerals within the quartzite, four distinct colors of stone come out of the quarries: gold, silver, white, and charcoal grey. Along with the blend of colors, the stone occurs in layers of varying thickness, making for an array of products for different uses and tastes.

One of most popular products, according to Forest, is Honey Ledgestone, used as a veneer on building exteriors. This stone is offered in four styles, ranging from thin, uniform stones for a tidy contemporary aesthetic, to a more classic look with a wider variety of shapes and colors.

Sunset Gold flagstone is another customer favorite. The thin layering in the quartzite produces flagstone that is relatively lightweight but very strong – even when only a half-inch thick. Thicker seams yield chunkier blocks two or three inches thick, useful for pool coping, stone walls, or stepping stones.

Forest says the Sunset Gold is particularly popular in California, “that’s a huge market for us,” she says, explaining that the warm colors tend to be the most in-demand, while grey tones are also enjoying an upswing in popularity lately.

Rocky Mountain Quartzite is mostly used outdoors, but works beautifully as interior tile or flooring, especially when seeking to “bring the outside in,” says Forest.

To learn about evolving tastes and needs, Forest travels around the country to different distributors where she keeps her ear to the ground to learn what designers, architects and customers want. “We try to learn what’s new, and how we can respond and improve,” she says.

Adaptation is the key to success

Northern Stone Supply’s current owner, Greg Osterhout, made the transition from Vice President to owner in 2008 – just at the onset of the recession. Sales slowed throughout the industry and many companies went bankrupt. Osterhout saw this as an opportunity to invest in the company and its processes. “He bought equipment from companies that were going out of business,” explains Forest, “then used the downtime to learn new methods.” In particular, Osterhout figured out a better way to fabricate thin veneer. Quartzite’s hardness and tenacity means that it’s notoriously slow to fabricate. Osterhout figured how to make the fabrication faster and more efficient, bringing down the price of the veneer. Forest didn’t elaborate on the method, stating proudly, “He’s got a little bit of a secret there.”

After the 2008 recession, sales of thin veneer skyrocketed. “It blew up,” Forest recalled, and the company was able to climb out of the recession with strong sales. Thin veneer continues to be one of Northern Stone’s best sellers.

The company now faces another challenge as COVID-19 grips the world, triggering widespread unemployment, and creating uncertainty for everyone. But Forest is bullish for the health of the business. “The housing market drives our sales,” she explains, and the company has many months’ worth of contracts to fulfill. Quarrying and production are proceeding apace, and Forest expects demand to remain steady.

Platinum sustainability

Northern Stone was the first company to achieve platinum level certification via the ANSI/NSC 373 sustainability program. “It’s not an easy certification,” says Forest, “It’s a big deal.” Forest feels that customers, designers, architects want to work with a company that shares their environmental and ethical values. “The certification is important,” she says, as a way to demonstrate a company’s commitment.

Osterhout is featured on the Natural Stone Council’s sustainability website, where he explained that the company was able to save both money and fuel by reducing engine idling. “We created an anti-idling policy that included educating our employees on the cost of excessive idling, adding anti-idling signage in cabs, and in most cases installing auto shut down timers on our large diesel equipment,” he wrote, adding that these improvements had duel benefits: “Good for the environment and our bottom line.”

The story behind the stone

While it’s possible to simply use generic materials originating overseas and purchased at a big box store, many customers are seeking more than that. A desire for locally sourced materials is playing an increasingly important role.

A stone’s place of origin “is one of the first things people ask about” when they visit stone yards, says Forest.

Forest sums up what Rocky Mountain Quartzite means to her: “This was quarried from a mountain; it came from near where I grew up.” This standout stone delivers on many levels: “People like the beauty, durability, and the story behind the stone.”

More from the American Stones Series

How to Tell If Your White Stone is a Granite, Quartzite, or Marble

One of the favorite parts of my job as a roving geologist is to share not just an appreciation for natural stone, but a deeper understanding of it. With a little guidance and practice, anyone can learn to recognize the properties and aesthetics of various types of stone. No matter a slab’s label, country of origin, or price tag, some basic geologic savviness can help us understand it better.

The process of identifying stones gets most confusing when they look alike, and nowhere is this more vexing than with white stones, which are popular, frequently mislabeled, and often misunderstood. But fear not. Even similar-looking stones can be sorted out by using a few basic guidelines.

Read on, as we step through the process of differentiating light-colored granites, quartzites, and marbles.

Granite has a distinct look, compared to quartzite and marble.

Granite is the most common type of natural stone in the trade and comes in a satisfyingly large range of colors and patterns. Despite their diverse aesthetics, granites have common elements that make them recognizable. Below are some rules of thumb. Please note that I’m referring to the general industry classification of granite, rather than the narrower geologists’ definition.

• Light colored granites have flecks or blocks of varying colors. White granites are rarely a homogeneous, even-toned color. Most light colored granites have more than one color in them, and it’s rare to have a white granite without any darker minerals at all.

• Individual minerals are visible. Look for blocky crystals of feldspar, glassy areas of quartz, and a smattering of darker colored minerals. Learn more about what different minerals look like.
• Sometimes granite has giant minerals! If the slab has minerals larger than couple of inches, then you’ve got a pegmatite. That’s special type of granite with super-sized crystals. Patagonia is one of the more dramatic examples of a granite pegmatite, and Tourmaline, Alpine, Alaska White, and Delicatus are other examples.
• If it contains garnet, it’s granulite or gneiss. Garnets are small, round minerals that are dark pink, burgundy, or reddish brown in color. Their presence is an instant giveaway that you’re looking at metamorphic variations of granite. Gneiss has stripes or bands of lighter and darker minerals, while granulite tends to have few or no stripes and is generally light colored overall. There are many white granulites on the market, including Bianco Romano, Colonial White, or Giallo Cream. Viscount White is an example of gneiss.
• Mica is common in granite. Mica is present in small amounts in granite, and it makes an appearance as glittery minerals that can be silver, gold, bronze, or metallic black. If a stone is mostly made of mica, then it’s schist.
• Granite can have quiet patterns or vivid movement. Leave it to Mother Nature to create waves of color, veins of contrasting minerals, and all sorts of other interesting effects. That’s a big part of the appeal of a natural stone.
• Read more about the variations, colors, and origins of granite.

Marble and quartzite look different from granite, but similar to each other.

Marble and quartzite look alike in several ways.

• They tend to be mostly light colored: white, light grey, cream. Darker colors are also possible.
• Marble and quartzite are usually fine grained overall; you can’t put your finger on an individual mineral grain.
• They often have layers or bands of contrasting colors. The layering can be straight, wavy, or chaotic.
• Slabs can have quiet patterns or vivid movement.
• If a slab has fossils, then it’s limestone, not marble. Limestone has a chalky or matte finish compared to either marble or quartzite.
• Read more about marble and quartzite.

To tell marble from quartzite, check their properties.

 The fact that these two stones look alike is why they are so frequently mislabeled and misunderstood. Your best bet is to rely on the way the stones behave rather than how they look. Thankfully, marble and quartzite have consistent traits that you can use to tell them apart.

• Quartzite is much harder than marble and slightly harder than granite.
  You can use a glass tile or a knife blade to gauge the hardness of a stone. Quartzite will leave a definite scratch on glass, and a knife blade will not easily scratch the stone (though it may leave a silvery mark on the stone, which is the metal rubbing off on the stone). Learn more about identifying quartzite in the Definitive Guide to Quartzite.

• Marble is relatively soft.
  A knife blade will make obvious scratch marks on marble; and marble will not scratch glass. Some marbles, like Super White or Fantasy Brown, may have isolated pockets of quartz amid an overall composition of marble. When in doubt, check a few different areas of the stone.
• Quartzite is not affected by acids.
  Vinegar, lemon, wine, citrus, or any other common acid won’t affect quartzite. Strong chemicals like oven cleaner or rust remover can damage almost any stone, though, so be careful with those.
• Marble is acid-sensitive.
  The mineral calcite is dissolved by acids, and many types of stone contain calcite, such as limestone, onyx, travertine, and marble. (Science trivia: this is why acid rain caused damage to buildings and monuments before we got a handle on the pollution that causes acid rain.) Dolomite is a mineral that is chemically similar to calcite, and it’s also affected by acids but not as quickly. In either case, acids leave an etch mark or a dull spot on the surface of the stone. Etches do not affect the structural integrity of a stone, and they can be polished out if need be. For people who love marble, etches are often considered a part of the living surface of the stone, which develops depth and character over time. If that idea makes you cringe, then you know marble is not for you. Choose quartzite or granite instead!

Granite, marble and quartzite can be porous…or not.

Some types of stone have small pore spaces within the stone, and a porous stone can absorb liquids and become stained. There are several geologic processes that affect a stone’s porosity. For example, if a stone does not get buried too deeply when it forms, tiny spaces can remain between mineral grains. Another possible cause of porosity is underground fracturing along fault lines where rocks grind up against each other. Sometimes groundwater dissolves away pieces of the stone. On the other hand, groundwater can also do the opposite – it can add bits of minerals that will fill in pore spaces.

So we just have to live with the fact that sometimes granite, marble, and quartzite are slightly porous, and sometimes they are not. That also means that porosity cannot be a guide to helping us identify a stone. We can’t say that a stone is porous therefore it’s marble, for example. Because plenty of marbles are dense and impermeable. The same is true for granite and quartzite, too.

The porosity of quartzite can be especially confusing, and you can learn more in the Deep Dive Into the Properties of Quartzite.

So while rules of thumb fail us, what we can do is test slabs to learn about their porosity – which is actually ideal, because you’ll get specific details on the slabs of interest.

Refer to How to Be Your Own Stone Sleuth for instructions and photos showing how to test your slab’s hardness, acid sensitivity, and porosity. Nothing can beat the hands-on information you’ll get from doing a little “sciencing” on various slabs, and it’s pretty fun, too.

So don’t let the array of white stones get the better of you. By learning a bit more about how different stones get their particular aesthetics and properties, you’ll be able to enjoy them all the more.

More from the Geology Series

Engineered quartz and natural quartzite are both popular choices for countertops, backsplashes, bathrooms, and more. Their names are similar, and are sometimes (incorrectly) used interchangeably. But even aside from the names, there’s a lot of confusion about these materials.

Here’s a quick and handy reference for understanding both engineered quartz and quartzite: where they come from, what they’re made of, and how they differ.

Quartzite is a natural stone.

Quartzite is 100% natural and comes directly from the earth. Quartzite has formed in locations all around the planet and the most well-known quartzite quarries are in Brazil. Quartzite is also quarried in the United States, Sweden, Canada, Norway, India, and Italy, among other locales. Dramatic settings like the Medicine Bow Mountains in Wyoming show off quartzite in its natural habitat, where an impressive massif of white quartzite rises above the surrounding terrain.

Medicine Bow Peak in Wyoming is made from white quartzite that is over a billion years old. Photo: Wikimedia Commons by Fredlyfish4.

Engineered quartz is manmade.

Even though the name “quartz” refers to a natural mineral, engineered quartz (sometimes also called “engineered stone”) is a manufactured product. It’s made from quartz particles bonded together with resin, pigments, and other ingredients. Manufactured quartz is made in factories in the United States, Europe, and Asia, among other locations.

Natural quartzite contains minerals, and nothing else.

All quartzites are made of 100% minerals, and are purely a product of nature. Quartz (the mineral) is the main ingredient in all quartzites, and some types of quartzite contain smaller amounts of other minerals that give the stone color and character. The diverse options in aesthetics are impressive—and all from the earth. So if you like calm monochrome, nature provides that. If wild streaks of color tug on your heart, nature’s got you covered.

Some examples:

Engineered quartz contains minerals, polyester, styrene, pigments, and tert-Butyl peroxybenzoate.

The exact blend of ingredients in engineered quartz varies by brand and color, and manufacturers tout the high percentage of minerals in their slabs. The oft-cited statistic is that manufactured quartz contains 93% mineral quartz. But there are two caveats. First, 93% is the maximum, and actual quartz content can be much lower. Secondly, that percentage is measured by weight, not volume. A particle of quartz weighs a lot more than a particle of resin. So if you want to know how much of a countertop surface is made of quartz, then you need to measure the ingredients by volume, not weight. Based on proportions of materials in PentalQuartz, for example, the product is around 74% mineral quartz when measured by volume, even though it’s 88% quartz by weight.

Quartzite is made from geologic processes, over millions of years.

Some people (me included!) love the idea of having a slice of geologic time in their home or office. Every natural stone is an expression of all of the time and events that shaped it. Each quartzite has its own life story, but many were deposited as beach sand, and then buried and compressed into solid rock to make sandstone. Then the stone was pushed deeper into Earth’s crust where it was further and compressed and heated into a metamorphic rock. During metamorphism, quartzite experiences temperatures somewhere between 800° and 3000° F, and pressures of at least 40,000 pounds per square inch (in metric units, that’s 400° to 1600° C and 300 MPa), all over the course of millions of years.

Natural quartzites are not all alike. There is variation in how deeply they were buried and for how long, and what types of conditions they endured. Because of this, some quartzites are somewhat porous (like Macaubus), while others are tightly bonded together (like Marine Blue, Taj Mahal, or Fusion). For an explanation of the different members of the quartzite family, check out A Deep Dive Into the Properties of Quartzite.

Engineered quartz is made in a mold.

Many quartz brands are made with the patented Breton process, which involves pouring the ingredients in slab-shaped molds, then subjecting the mixture to a vacuum, vibration, and pressure. In the words of the manufacturer, it’s called “compaction by vibrocompression vacuum process.” The Breton process compresses slabs at around 30 pounds per square inch, and applies heat up to 360° F for around 40 minutes (in metric, that’s 180° C and 0.2 MPa). For comparison, that’s about the same amount of pressure in a car tire, and the same temperature and duration as if baking a casserole. Then the slabs are cured in a kiln, cooled, and polished. Compared to nature’s way of making stone, this is certainly quicker and more controlled, but the amount of heat and pressure used to manufacture a slab are far less than what happens in nature.

Because quartz particles are encased in resin, engineered quartz ends up having low porosity even though it is not compressed as much as natural quartzite (water absorption up to 0.02% in weight, according to Breton). On the other hand, the presence of resin means that engineered quartz is softer than natural quartzite.

Quartzite can be used indoors and out.

Natural quartzite is at home in many applications, from countertops and flooring, to outdoor kitchens and cladding. Harsh weather and UV light won’t affect the stone.

Engineered stone is best left indoors.

As I learned when I left several quartz slabs outside for a few months, the resins in engineered stone will turn yellow in the sunlight.

Quartzite is often misunderstood.

An unfortunate side effect of the desirability of quartzite is the temptation to sell stones as quartzite when they are not quartzite. Thus, quartzite is commonly mislabeled, which has resulted in widespread confusion about the properties of the stone. So-called “soft quartzite” is usually marble, which has entirely different properties than real quartzite. Simple diagnostic tests can be used to differentiate quartzite and marble. Furthermore, some sandstones are sold as quartzite, which further adds to the mix-up. Sandstone and quartzite have the same mineral ingredients (quartz), but quartzite has much lower porosity, as is explained in the Deep Dive into the Properties of Quartzite. Thankfully, it seems that both industry pros and consumers are becoming more discerning about what quartzite truly is, or is not.

Engineered quartz is misunderstood, too.

One well-known brand of manufactured quartz literally calls itself natural stone, which it isn’t. Manufactured quartz is sometimes thought to be maintenance free, which would be nice, but engineered surfaces are not immune to staining, chipping, scratching, or damage from excessive heat. Just as with any other material, users of manufactured quartz surfaces need to be mindful of the properties of engineered quartz and the particular requirements for its care.

Some misconceptions about engineered quartz are addressed in Sifting Through the Confusion about Manmade Quartz Surfaces and Do Engineered Quartz Countertops Stain?

Quartzite needs sealing.

The most common problem with quartzites is inadequate sealing – particularly along the edges and cut surfaces. As described above, some quartzites are porous and care must be taken to seal the stone. When in doubt, be sure to work with a fabricator who is experienced with the particular quartzite you are considering.

Engineered quartz should be protected from heat and not scrubbed too hard.

In a series of tests, major brands of engineered quartz stood up reasonably well to staining, but were damaged by scrubbing with abrasive cleaners or scouring pads. Exposure to hot, dirty cookware damaged some types of quartz, as was shown in a performance comparison of countertop materials.

Which should you use?

There is no simple answer to this question. Each material has its devoted fans and selling points. No matter which surface you choose, be sure to obtain samples that you can test, work with a reputable dealer and fabricator, and take some time to learn about the product. While labels and misconceptions can cause confusion, the combination of informed customers and experienced professionals can help ensure that materials are used in ways that allow them to perform well, last a long time, and look terrific every day.

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