Fresh from church on a cool, overcast Sunday morning in Spruce Pine, North Carolina, Alex Glover slides onto the plastic bench of a McDonald’s booth. He rummages through his knapsack, then pulls out a plastic sandwich bag full of white powder. “I hope we don’t get arrested,” he says. “Someone might get the wrong idea.”

Glover is a recently retired geologist who has spent decades hunting for valuable minerals in the hillsides and hollows of the Appalachian Mountains that surround this tiny town. He is a small, rounded man with little oval glasses, a neat white mustache, and matching hair clamped under a Jeep baseball cap. He speaks with a medium‑strength drawl that emphasizes the first syllable and stretches some vowels, such that we’re drinking CAWWfee as he explains why this remote area is so tremendously important to the rest of the world.

Spruce Pine is not a wealthy place. Its downtown consists of a somnambulant train station across the street from a couple of blocks of two‑story brick buildings, including a long‑closed movie theater and several empty storefronts.

Excerpted from The World in a Grain by Vince Beiser. Penguin Random House

The wooded mountains surrounding it, though, are rich in all kinds of desirable rocks, some valued for their industrial uses, some for their pure prettiness. But it’s the mineral in Glover’s bag—snowy white grains, soft as powdered sugar—that is by far the most important these days. It’s quartz, but not just any quartz. Spruce Pine, it turns out, is the source of the purest natural quartz—a species of pristine sand—ever found on Earth. This ultra‑elite deposit of silicon dioxide particles plays a key role in manufacturing the silicon used to make computer chips. In fact, there’s an excellent chance the chip that makes your laptop or cell phone work was made using sand from this obscure Appalachian backwater. “It’s a billion‑dollar industry here,” Glover says with a hooting laugh. “Can’t tell by driving through here. You’d never know it.”

Rocks like these high-grade silica samples mined near Charlotte, North Carolina, are the basis for modern computer chips. Charles O'Rear/Getty Images

In the 21st century, sand has become more important than ever, and in more ways than ever. This is the digital age, in which the jobs we work at, the entertainment we divert ourselves with, and the ways we communicate with one another are increasingly defined by the internet and the computers, tablets, and cell phones that connect us to it. None of this would be possible were it not for sand.

Most of the world’s sand grains are composed of quartz, which is a form of silicon dioxide, also known as silica. High‑purity silicon dioxide particles are the essential raw materials from which we make computer chips, fiber‑optic cables, and other high‑tech hardware—the physical components on which the virtual world runs. The quantity of quartz used for these products is minuscule compared to the mountains of it used for concrete or land reclamation. But its impact is immeasurable.

about the author Vince Beiser is an award-winning writer whose work has appeared in WIRED, Harper's, The Atlantic, Mother Jones, and Rolling Stone, among other publications. A graduate of the University of California at Berkeley, he lives in Los Angeles.

Spruce Pine’s mineralogical wealth is a result of the area’s unique geologic history. About 380 million years ago the area was located south of the equator. Plate tectonics pushed the African continent toward eastern America, forcing the heavier oceanic crust—the geologic layer beneath the ocean’s water—underneath the lighter North American continent. The friction of that colossal grind generated heat topping 2,000 degrees Fahrenheit, melting the rock that lay between 9 and 15 miles below the surface. The pressure on that molten rock forced huge amounts of it into cracks and fissures of the surrounding host rock, where it formed deposits of what are known as pegmatites.