Sand is everywhere – from the building you live in to the roads you drive on. Sand enables modern life, but it’s starting to run out, and its mining and use destroy the environment. In this reading recommendation, Vince Beiser illuminates what sand makes possible, why sand grips the human imagination, and offers insights into the political and environmental issues surrounding sand.
Recommendation
Sand is the groundwork for virtually everything in modern life. The buildings you live and work in and the roads you drive on are made of sand. Sand enables modern life, but it’s starting to run out, and its mining and use destroy the environment. Award-winning journalist Vince Beiser illuminates what sand makes possible, why sand grips the human imagination, and offers insights into the political and environmental issues surrounding sand.
Take-Aways
- Sand is the most significant material in the world.
- The invention of concrete – which sand and gravel comprise – transformed the way people live.
- Asphalt and concrete changed the way Americans move from place to place.
- Sand’s use in making glass shaped modern life.
- Sand is crucial for making computer chips, and thus makes 21st-century life possible.
- Fracking requires sand, and has made America a top oil and gas producer.
- Beaches around the world are disappearing, and sand mining is a cause.
- Sand islands in the sea are obliterating ecosystems.
- Concrete is taking over the world.
Sand is the most significant material in the world.
You may think sand is the most ordinary substance, useful for recreational spots like beaches, but in fact it’s necessary for the greater part of the world most people live in today. If you consider how you live and work on an average day, much of what you do relies on sand. The buildings you live and work in, for example, contain vast amounts of concrete, of which sand is a foundational material. Sand is a crucial material in the windows you gaze out of in your office or living room. They are glass, which is made of sand, as are the roads and sidewalks you drive and walk on, and the shopping malls you visit. The chips that make your smartphone, iPad and laptop intelligent and useful require sand.
“You may not realize it, but sand is there, making the way you live possible, in almost every minute of your day.”
Sand makes 21st-century life possible. But sand has become scarce, and people pursue it fiercely. Earth’s population keeps growing, and people need more and more sand to live and work, especially in today’s digital, globalized economy.
The invention of concrete – which sand and gravel comprise – transformed the way people live.
The invention of concrete fundamentally changed human life as much as fire and electricity did. Necessary for the construction of massive buildings and the roads people travel on around the world, concrete manufacture relies on relatively straightforward materials. People make concrete by combining sand, gravel, cement and water, with sand and gravel as the dominant ingredients. The result dries into a hard, stone-like substance.
“Concrete is the skeleton of the modern world, the scaffold on which so much else is built.”
Concrete has all the weaknesses and limitations of stone, but when iron and steel reinforce it, it offers a variety of uses. Reinforced concrete helped the people of the 20th century realize their ambitions. Reinforced concrete made the construction of the Panama Canal feasible, changing shipping routes for the entire world. The Hoover Dam across the Colorado River was once the world’s biggest, and demanded vast quantities of sand and gravel, much of it mined a few miles from the dam. Reinforced concrete gave rise to a new architectural aesthetic, like the corkscrew shapes of Frank Lloyd Wright’s Solomon R. Guggenheim Museum, for example.
Asphalt and concrete changed the way Americans move from place to place.
The United States today organizes around a vast network of interconnected paved highways and roads. In the early 20th century, few roads connected cities, and those that did were mostly unpaved. Following World War I, the US military believed America’s roads needed dramatic improvement. That was exactly what President Dwight D. Eisenhower did when he initiated construction of the interstate highway system, which eventually consumed thousands of tons of concrete and more than a billion tons of sand and gravel. In an era in which everyone wanted a car, good, paved roads proved crucial. By the middle of the 1950s, more than 50% of American families owned cars. Congress approved funds for this vast highway project, which would create some 41,000 miles of road, in 1956. It didn’t reach completion until 1991, at a price of close to $130 billion.
Sand’s use in making glass shaped modern life.
Glass is ubiquitous in modern life. People look out into their streets or their yards through glass. People drink from glass cups in rooms lit by glass bulbs. Glass makes it possible to see things it would otherwise be impossible to see. Glasses, cameras, microscopes and telescopes and everything they bring with them all depend on glass lenses. The sand that manufacturers melt down to make glass requires more specialized grains that are “95 percent pure silicon dioxide.”
“The booming cities don’t need sand only for concrete; they need if for glass. All those new buildings need windows. The new cars on the new highways need windshields.”
When former coal-mine child laborer Mike Owens invented a glass-bottle-making machine in 1903, he created something that the American Society of Mechanical Engineers called the “most significant advance in glass production in over 2,000 years.” Owens’s machine helped make glass bottles an everyday item worldwide. In 1952, a British engineer invented a process for making sheet glass that builders could use as windows in large buildings. Today, rapidly expanding cities all over the world need sand for concrete and for glass. The demand for glass, and the kinds of sand that glass can be made from, is only increasing.
Sand is crucial for making computer chips, and thus makes 21st-century life possible.
Sand in the form of “high-purity silicon dioxide particles” is crucial for manufacturing the hardware for digital technologies, including computer chips and fiber-optic cables.
“Most of us never think about how our high-tech industries depend on sand.” ”
Early on, engineers regarded silicon, which is a “semiconductor,” as a worthy material for creating the transistors that would drive and streamline computers. When Intel offered the first commercially available computer chip in 1971, it contained 2,250 transistors. A contemporary computer chip houses billions of transistors. Computer chips drive the internet and everything on it. Computer chips are one of the most intricate objects human beings manufacture, and sand is their basic element.
Fracking requires sand, and has made America a top oil and gas producer.
Fracking makes it possible to extract vast amounts of oil and gas from areas of North Dakota, Texas, Ohio and Pennsylvania. Fracking helps the United States lead the world in the extraction of oil and gas. Fracking requires sand. Specialists have long understood that shale rock contains significant quantities of hydrocarbons, but the density of shale makes it difficult for hydrocarbons to move out of it and form reserves. This can be sidestepped by fracturing, or fracking, the rock and injecting a “highly pressurized mix of water, chemicals and sand.” The hydrocarbons move through the cracks in the shale. The sand keeps the cracks open.
“America’s fracking fields are the latest front to which we have deployed armies of sand to maintain our lifestyle.”
The development of “horizontal drilling,” which enables reaching even more oil and gas resources, drove a dramatic expansion of fracking. Since 2003, the amount of sand used for fracking has increased exponentially. Fracking uses more sand than concrete, glass and silicon chips do. Fracking brings a variety of negative environmental effects – water resource pollution, earthquakes, and an increased risk of cancer and silicosis.
Beaches around the world are disappearing, and sand mining is a cause.
Everyone loves a beach with beautiful white sand. And beaches around the world are worth billions of dollars. In many places, like Fort Lauderdale, Florida, beaches are tourist attractions that employ a lot of people. Fort Lauderdale’s most vexing trouble is that its beautiful beaches are gradually vanishing. Traditionally, the sand on Fort Lauderdale’s beaches would go through a natural process of erosion and restoration. In the last century, the marinas and jetties that people have built along the Atlantic coast obstructed this natural process. Beaches around the world, from Southern California to Europe and Asia, are also vanishing.
“On shorelines around the world, in countries rich and poor, supine armies of sand offer themselves up as tourist attractions.”
Coastal development and river dams drive the destruction of beaches. River dams obstruct the movement of water and sand that restores beaches. Sand mining in rivers makes the situation even worse. Sand mining in South Africa has decimated the flow of sand to the beaches in Durban, and the dredging of San Francisco Bay may affect the beaches nearby. In Morocco, Algeria and Russian-occupied Crimea, smugglers illegally mine the beaches themselves.
With seas rising as a result of climate change and beaches vanishing, coastal communities are increasingly at risk. Since natural processes no longer maintain many beaches, people turn to artificial “beach replenishment,” which has become an industry worth billions. Federal and state governments have spent billions of taxpayer dollars reconstructing beaches around the United States. Beaches around the world have been rebuilt in this way. Sand mined to rebuild the beaches comes from other locations.
People tend to think of beaches as a part of the nature, but many beaches are “engineered environments built for profit,” and the original, natural beach and shore have vanished. The creation of artificial beaches can be damaging to the environment, because artificial beaches affect ecosystems and habitats. The only serious alternative to rebuilding beaches is the least likely event: moving cities farther away from the coast. Repairing beaches is unsustainable in the long run. Sand will simply run out.
Sand islands in the sea are obliterating ecosystems.
Austrian-born Josef Kleindienst is investing millions to turn a chain of artificial sand islands off the coast of Dubai in the Persian Gulf into luxurious holiday resorts with European themes. Kleindienst’s project may well be the largest group of artificial islands ever fabricated. His project uses hundreds of millions of tons of sand from the bottom of the Persian Gulf. With their cosmopolitan themes, the resorts may be singularly pretentious, but they aren’t the only attempt to build new land around the world. Similar projects are rising in China, Japan, Nigeria and California’s Pacific coast.
“The bigger question is, can the planet handle the whole way of life Dubai both represents and embodies?”
Building new islands in the sea with sand destroys the environment. Dredging large amounts of sand from the bottom of the sea annihilates entire ecosystems. And in places like China, the creation of new, offshore land masses can raise dangerous geopolitical issues. On artificial islands in the South China Sea, China immediately began constructing military installations, air and naval bases that raise alarms in the international community.
Concrete is taking over the world.
Since the turn of the millennium, nearly seven million people have moved to Shanghai. During that same period, more skyscrapers were built in Shanghai than exist in New York City, and the city added a major international airport and many new roads. Builders had to manufacture staggering amounts of concrete and use equally staggering amounts of sand. They mined most of that sand from the bottom of the Yangtze River and Poyang Lake, 400 miles from Shanghai. Sand mining wreaked havoc on the river and the lake. Humans need this much concrete and sand, because people are moving to cities everywhere in the world. In Africa, the Middle East, Latin America and Asia, cities are turning into “megacities.” Cities and the infrastructure that goes along with them couldn’t grow to this size or at this speed without the extensive use of concrete.
“The sands of time are running out.”
Once people believed natural resources were limitless. No one considered how humans might sustain their lives, with their houses and malls, laptops and cellphones, when Earth’s population is seven billion. Humans must now live lives on more durable and sustainable foundations.
About the author
Vince Beiser is an award-winning journalist. The World in a Grain, his first book, was a finalist for the PEN/E. O. Wilson Literary Science Writing Award and a California Book Award. His work has appeared in Wired, Harper’s, The Atlantic, Mother Jones, and the New York Times, among other publications. A graduate of the University of California at Berkeley, he lives in Los Angeles.
Genres
Nonfiction, History, Science, Nature, Environment, Economics, Technology, Natural History, Microhistory, Earth Science, Engineering, Transportation, Materials Science, Rocks and Minerals, Environmental Science
Table of Contents
1 The Most Important Solid Substance on Earth 1
Part I How Sand Built the Twentieth Century’s Industrialized World
2 The Skeleton of Cities 29
3 Paved with Good Intentions 49
4 The Thing That Lets Us See Everything 75
Part II How Sand Is Building the Twenty-First Century’s Globalized, Digital World
5 High Tech, High Purity 101
6 Fracking Facilitator 119
7 Miami Beach-less 141
8 Man-Made Lands 169
9 Desert War 203
10 Concrete Conquers the World 217
11 Beyond Sand 235
Acknowledgments 259
Notes 263
Bibliography 283
Index 287
Overview
A finalist for the PEN/E. O. Wilson Literary Science Writing Award
The gripping story of the most important overlooked commodity in the world—sand—and the crucial role it plays in our lives.
After water and air, sand is the natural resource that we consume more than any other—even more than oil. Every concrete building and paved road on Earth, every computer screen and silicon chip, is made from sand. From Egypt’s pyramids to the Hubble telescope, from the world’s tallest skyscraper to the sidewalk below it, from Chartres’ stained-glass windows to your iPhone, sand shelters us, empowers us, engages us, and inspires us. It’s the ingredient that makes possible our cities, our science, our lives—and our future.
And, incredibly, we’re running out of it.
The World in a Grain is the compelling true story of the hugely important and diminishing natural resource that grows more essential every day, and of the people who mine it, sell it, build with it—and sometimes, even kill for it. It’s also a provocative examination of the serious human and environmental costs incurred by our dependence on sand, which has received little public attention. Not all sand is created equal: Some of the easiest sand to get to is the least useful. Award-winning journalist Vince Beiser delves deep into this world, taking readers on a journey across the globe, from the United States to remote corners of India, China, and Dubai to explain why sand is so crucial to modern life. Along the way, readers encounter world-changing innovators, island-building entrepreneurs, desert fighters, and murderous sand pirates. The result is an entertaining and eye-opening work, one that is both unexpected and involving, rippling with fascinating detail and filled with surprising characters.
Review/Endorsements/Praise/Award
“[An] impassioned and alarming report on sand…. In Beiser’s artful telling, the planet is caught up in a vicious, sand-fueled cycle.” —Washington Post
“Beiser peppers research with first-person interviews in an engaging and nuanced introduction to the ways sand has shaped the world…. stunning.” —NPR
“Beiser’s eye-opening study clarifies the science and the huge role of sand in heavy and high-tech industry. Perhaps most compelling is his exposé of sand mining, which obliterates islands, destroys coral reefs and marine biodiversity, and threatens livelihoods. A powerful lens on an under-reported environmental crisis.” —Nature
“Whether in Chippewa Falls, Wisconsin, or India, [Beiser] exhibits a flare for detailing the human drama through prose.” —Los Angeles Review of Books
“I thought I knew the basics of sustainability, but this lucid, eye-opening book made me feel like a dolt in the best possible aha-moment way: I’d simply never registered how much of the contemporary world—our concrete and glass buildings and asphalt roads and silicone-based digital devices and so much more—is entirely, voraciously sand-dependent. And the looming global sand crisis: who knew?” —Kurt Andersen, author ofFantasyland: How America Went Haywire: A 500-Year History
“A fresh history of ‘the most important solid substance on Earth, the literal foundation of modern civilization.’ Books on a single, familiar topic (salt, cod, etc.) have an eager audience, and readers will find this an entirely satisfying addition to the genre.” —Kirkus Reviews
“The book is at its urgent best in chapters on the black market in sand and the sand mafias that brutally exercise control over resources… Breezily written and with insights on every page, this is an eye-opening look at a resource too often taken for granted.” —Publishers Weekly
“A rich study of one of the world’s most abundant natural resources: sand. With a balance of statistics, science, history, on-the-scene reporting and some healthy environmental skepticism, The World in a Grain highlights the ways this ubiquitous global commodity has been essential to human development and advancement.” —Shelf Awareness
“The World in a Grain is nothing less than one of the best reporters working today unpacking the literal foundations of civilization. Everything we are, everywhere we live, is built on or out of sand, and Vince Beiser tells the best story of where that sand comes from, who moves it, and what they build from it. It’s a whole new way of seeing the world.” —Adam Rogers, author of Proof: The Science of Booze
“Modern life, as Vince Beiser compellingly explains, is literally made of sand. Yet we have been so profligate with this seemingly inexhaustible resource that for many uses in many parts of the world we are running out. The World in a Grain is a chronicle of innovation and greed and heedless waste—in brief, the story of civilization.” —David Owen, author of Where the Water Goes
“A riveting, wonderfully written investigation into the many kinds of castles the world has built out of sand. You’ll find something new, and something fascinating, on every page. Perhaps even in every paragraph.” —Nicholas Thompson, author of The Hawk and the Dove
“Sand shortage? Black market in sand? Secret sand heists? Who knew? I certainly didn’t before reading this lively and eye-opening book about a material I’d always assumed almost infinite. Vince Beiser shows, with great skill, that this key component of our fragile, over-consuming planet we need to better understand, conserve and protect.” —Adam Hochschild, author of King Leopold’s Ghost and Bury the Chains
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Chapter 1
The Most Important Solid Substance on Earth
This book is about something most of us barely ever think about and yet can’t live without. It is about the most important solid substance on Earth, the literal foundation of modern civilization.
It is about sand.
Sand? Why is this humblest of materials, something that seems as trivial as it is ubiquitous, so significant?
Because sand is the main material that modern cities are made of. It is to cities what flour is to bread, what cells are to our bodies: the invisible but fundamental ingredient that makes up the bulk of the built environment in which most of us live.
Sand is at the core of our daily lives. Look around you right now. Is there a floor beneath you, walls around, a roof overhead? Chances are excellent they are made at least partly out of concrete. And what is concrete? It’s essentially just sand and gravel glued together with cement.
Take a glance out the window. All those other buildings you see are also made from sand. So is the glass in that window. So are the miles of asphalt roads that connect all those buildings. So are the silicon chips that are the brains of your laptop and smartphone. If you’re in downtown San Francisco, in lakefront Chicago, or at Hong Kong’s international airport, the very ground beneath you is likely artificial, manufactured with sand dredged up from underwater. We humans bind together countless trillions of grains of sand to build towering structures, and we break apart the molecules of individual grains to make tiny computer chips.
Some of America’s greatest fortunes were built on sand. Henry J. Kaiser, one of the wealthiest and most powerful industrialists of twentieth-century America, got his start selling sand and gravel to road builders in the Pacific Northwest. Henry Crown, a billionaire who once owned the Empire State Building, began his own empire with sand dredged from Lake Michigan that he sold to developers building Chicago’s skyscrapers. Today the construction industry worldwide consumes some $130 billion worth of sand each year.
Sand lies deep in our cultural consciousness. It suffuses our language. We draw lines in it, build castles in it, hide our heads in it. In medieval Europe (and a classic Metallica song), the Sandman helped ease us into sleep. In our modern mythologies, the Sandman is a DC superhero and a Marvel supervillain. In the creation myths of indigenous cultures from West Africa to North America, sand is portrayed as the element that gives birth to the land. Buddhist monks and Navajo artisans have painted with it for centuries. “Like sands through the hourglass, so are the days of our lives,” intone the opening credits of a classic American soap opera. William Blake encouraged us to “see a world in a grain of sand.” Percy Bysshe Shelley reminded us that even the mightiest of kings end up dead and forgotten, while around them only “the lone and level sands stretch far away.” Sand is both minuscule and infinite, a means of measurement and a substance beyond measuring.
Sand has been important to us for centuries, even millennia. People have used it for construction since at least the time of the ancient Egyptians. In the fifteenth century, an Italian artisan figured out how to turn sand into fully transparent glass, which made possible the microscopes, telescopes, and other technologies that helped drive the Renaissance’s scientific revolution.
But it was only with the advent of the modern industrialized world, in the decades just before and after the turn of the twentieth century, that people really began to harness the full potential of sand and begin making use of it on a colossal scale. It was during this period that sand went from being a resource used for widespread but artisanal purposes to becoming the essential building block of civilization, the key material used to create mass-manufactured structures and products demanded by a fast-growing population.
At the dawn of the twentieth century, almost all of the world’s large structures-apartment blocks, office buildings, churches, palaces, fortresses-were made with stone, brick, clay, or wood. The tallest buildings on Earth stood fewer than ten stories high. Roads were mostly paved with broken stone, or more likely, not paved at all. Glass in the form of windows or tableware was a relatively rare and expensive luxury. The mass manufacture and deployment of concrete and glass changed all that, reshaping how and where people lived in the industrialized world.
Then in the years leading up to the twenty-first century, the use of sand expanded tremendously again, to fill needs both old and unprecedented. Concrete and glass began rapidly expanding their dominion from wealthy Western nations to the entire world. At roughly the same time, digital technology, powered by silicon chips and other sophisticated hardware made with sand, began reshaping the global economy in ways gargantuan and quotidian.
Today, your life depends on sand. You may not realize it, but sand is there, making the way you live possible, in almost every minute of your day. We live in it, travel on it, communicate with it, surround ourselves with it.
Wherever you woke up this morning, chances are good it was in a building made at least partly out of sand. Even if the walls are made of brick or wood, the foundation is most likely concrete. Maybe it’s also plastered with stucco, which is mostly sand. The paint on your walls likely contains finely ground silica sand to make it more durable, and may include other forms of high-purity sands to increase its brightness, oil absorption, and color consistency.
You flicked on the light, provided by a glass bulb made from melted sand. You meandered to the bathroom, where you brushed your teeth over a sink made of sand-based porcelain, using water filtered through sand at your local purification plant. Your toothpaste likely contained hydrated silica, a form of sand that acts as a mild abrasive to help remove plaque and stains.
Your underwear snapped into place thanks to an elastic made with silicone, a synthetic compound also derived from sand. (Silicone also helps shampoo make your hair shinier, makes shirts less wrinkle-prone, and reinforced the boot sole with which Neil Armstrong made the first footprint on the moon. And yes, most famously, it has been used to enhance women’s busts for more than fifty years.)
Dressed and ready, you drove to work on roads made of concrete or asphalt. At the office, the screen of your computer, the chips that run it, and the fiber-optic cables that connect it to the Internet are all made from sand. The paper you print your memos on is probably coated with a sand-based film that helps it absorb printer ink. Even the glue that makes your sticky notes stick is derived from sand.
At day’s end, you flopped down with a glass of wine. Guess what? Sand was used to make the bottle, the glass, and even the wine. Wine is sometimes made with a dash of colloidal silica, a gel form of silicon dioxide used as a “fining” agent to improve the beverage’s clarity, color stability, and shelf life.
Sand, in short, is the essential ingredient that makes modern life possible. Without sand, we couldn’t have contemporary civilization.
And believe it or not, we are starting to run out.
Though the supply might seem endless, usable sand is a finite resource like any other. (Desert sand generally doesn’t work for construction; shaped by wind rather than water, desert grains are too round to bind together well.) We use more of this natural resource than of any other except air and water. Humans are estimated to consume nearly 50 billion tons of sand and gravel every year. That’s enough to blanket the entire state of California. It’s also twice as much as we were using just a decade ago.
Today, there is so much demand for sand that riverbeds and beaches around the world are being stripped bare of their precious grains. Farmlands and forests are being torn up. And people are being imprisoned, tortured, and murdered. All over sand.
The key factor driving our world’s unprecedented consumption of this humblest of materials is this: the number and size of cities is exploding. Every year there are more and more people on the planet, and every year more and more of them move to cities, especially in the developing world.
The scale of this migration is staggering. In 1950, some 746 million people-less than one-third of the world’s population-lived in cities. Today, the number is almost 4 billion, more than half of all the people on Earth. The United Nations predicts that another 2.5 billion will join them in the next three decades. The global urban population is rising by about 65 million people annually; that’s the equivalent of adding eight New York Citys to the planet every single year.
To build these cities of concrete, asphalt, and glass, humans are pulling sand out of the ground in exponentially increasing amounts. The overwhelming bulk of it goes to make concrete, by far the world’s most important building material. In a typical year, according to the United Nations Environment Programme, the world uses enough concrete to build a wall 88 feet high and 88 feet wide right around the equator. China alone used more cement between 2011 and 2013 than the United States used in the entire twentieth century.
There is such intense need for certain types of construction sand that places like Dubai, which sits on the edge of an enormous desert in the Arabian Peninsula, are importing sand from Australia. That’s right: exporters in Australia are literally selling sand to Arabs.
What is sand, anyway? That simple syllable comprises a panoply of tiny objects of many shapes and sizes made of many different substances. As defined by the Udden-Wentworth scale, the most commonly used geologic standard, the term sand encompasses loose grains of any hard material with a diameter between 2 and 0.0625 millimeters. That means the average grain of sand is a tad larger than the width of a human hair. Those grains can be made by glaciers grinding up stones, by oceans degrading seashells and corals (many Caribbean beaches are made of decomposed shells), even by volcanic lava chilling and shattering upon contact with air or water. (That’s where Hawaii’s black sand beaches come from.)
Nearly 70 percent of all sand grains on Earth, however, are quartz. These are the ones that matter most to us. Quartz is a form of silicon dioxide, or SiO2, also known as silica. Its components, silicon and oxygen, are the most abundant elements in the Earth’s crust, so it’s no surprise that quartz is one of the most common minerals on Earth. It is found abundantly in the granite and other rocks that form the world’s mountains and other geologic features.
Most of the quartz grains we use were formed by erosion. Wind, rain, freeze-thaw cycles, microorganisms, and other forces eat away at mountains and other rock formations, breaking grains off their exposed surfaces. Rain then washes those grains downhill, sweeping them into rivers that carry countless tons of them far and wide. This waterborne sand accumulates in riverbeds, on riverbanks, and on the beaches where the rivers meet the sea. Over the centuries, rivers periodically overflow their banks and shift their courses, leaving behind huge deposits of sand in what has become dry land. Quartz is tremendously hard, which is why quartz grains survive this long, bruising journey intact while other mineral grains disintegrate.
Over millions of years, sands are often buried under newer layers of sediment, uplifted into new mountains, then eroded and transported once again. “Sand grains have no souls, but they are reincarnated,” writes geologist Raymond Siever in his book Sand. “Each cycle of deposition, burial, uplift and erosion renews the sand grains and rounds each grain a little more.” The average time for this cycle is 200 million years. The next time you dump sand out of your shoes, give those grains a little respect: they may predate the dinosaurs.
In the wild, quartz always comes mixed with bits of other materials: iron, feldspar, whatever other minerals prevail in the local geology. (Pure quartz is transparent, but quartz grains are often stained by oxidation. That coloring, plus the presence of other types of grains, is why most beaches and sand deposits you see are various shades of yellow or brown.) A certain amount of those other substances need to be filtered out before the sand can be used to make concrete, glass, or other products.
You can think of sand sort of like a colossal army, or a group of related armies, made up of quintillions of tiny soldiers. Only these armies are deployed not to kill, but to create. Rather than destroy, these soldiers build structures and products and perform services for us.
At first glance, sand grains, like uniformed troops, all look pretty much the same. In fact, though, there are many different types, with different attributes, strengths, and weaknesses, which in turn determine the uses to which they can be put. Some are prized for their hardness, some for their pliancy; some for their roundness, some for their angularity; some for their color, some for their purity. Some sands, like specially chosen commandos, are put through elaborate physical or chemical processes to alter their capabilities, or are combined with other materials to perform tasks they could not in their original state.
Construction sand-the hard, angular grains used primarily to make concrete-are the infantry of this army. This kind of sand is abundant, easily found, and not especially pure. Its grains are mainly quartz, but include other minerals, which vary depending on where the sand was mined. Construction sand can be found in virtually every country, often mixed with its indispensable partner, gravel. The construction industry refers to sand and gravel together as aggregate; the difference between sand and gravel is mainly just size. These particles are drafted into service from riverbeds, beaches, or land quarries. Sand and gravel aggregates are put to work together to make concrete, while sand is deployed on its own to make other construction materials like mortar, plaster, and roofing components.
Marine sands-the naval wing of the army, found on the ocean floor-are of similar composition, making them useful for artificial land building, such as Dubai’s famous palm-tree-shaped man-made islands. These underwater grains can also be used for concrete, but that requires washing the salt off them-an expensive step most contractors would rather avoid.
Silica sands are purer-at least 95 percent silica-and are found in fewer places than construction or marine sand. Also called industrial sands, they’re the Special Forces of the sand army, capable of being put to more sophisticated purposes than the average foot soldier. These are the sands you need to make glass. Higher-purity sands are especially prized: the sands of north-central France’s Fontainebleau region, for instance, are upward of 98 percent pure silica. Europe’s finest glassmakers have relied on them for centuries. Silica sands are also used to help make molds for metal foundries, add luster to paint, and filter the water in swimming pools, among many other tasks. Some of the unique properties of industrial sands suit them for highly specific jobs. The silica sands of western Wisconsin, for instance, have a particular shape and structure that make them ideal for use in fracking for oil and gas.
