IRA FLATOW: This is Science Friday. I’m Ira Flatow. You know, beach season is in full swing. And no trip to the seaside is complete without the sand. But that is just the beginning of the wonders of sand.

Sand is all around us– in tall concrete skyscrapers, computer chips in your smartphones. If you feel the Earth move under your feet, it might be sand. Did you know that not all sand is created equally? The highest quality sand, the kind used to make computer chips, comes from a special mine in North Carolina.

And our need for sand has created sand cartels, black markets for the grain. Sand thieves in Jamaica stole part of a beach right off the island. My next guest says that sand is the most important solid substance on Earth and is at the core of our daily lives. He’s here to talk about these tiny grains.

Vince Beiser is a journalist and author of the book The World in a Grain– The Story of Sand and How It Transformed Civilization. And you can read an excerpt from this book on our website, sciencefriday.com/beach. Welcome to Science Friday.

VINCE BEISER: Thanks. It’s great to be here.

IRA FLATOW: Hey, fascinating book. I thought we know about sand, but we didn’t. We know about the sand on the beach. There’s sand in sandbags, in deserts. What is the definition of sand?

VINCE BEISER: So the word itself just means any little bits, grains of any hard substance. If you really want to get technical, since this is Science Friday, it’s anything with a diameter of between 2 millimeters and 0.0625 millimeters.

So it means that sand can be crushed up shells. It can be crushed up volcanic rock. It can be lots of things. But most sand in the world and the sand that we use so much of is mostly quartz sand, silicon dioxide.

IRA FLATOW: So it’s not like the White Cliffs of Dover. They’re not made from the quartz sand, right?

VINCE BEISER: I don’t think so. Not an expert on those, but they sure don’t look like it.

IRA FLATOW: So not all sand is equal. There are different grades of sand. Tell us about that. What makes the mine in North Carolina so special for making computer chips?

VINCE BEISER: So there are indeed a lot of different kinds of sand that can be used for different applications. So the stuff that we use the most, like I said, is quartz sand, which is very abundant. You find it all over the world. In fact, it’s the most abundant thing on the planet’s surface.

We can use that stuff for concrete, which is the number one thing that we use sand for by far– is concrete. For concrete, you don’t need sand that’s especially pure– in other words, that has a super high quartz content.

The next step up is sand that you use for glass making. And for that, you need sand that’s much higher purity. Glass is basically nothing but quartz sand that’s been melted down. But to get nice, clear glass, you need to start with quartz sand that’s upwards of 95% pure.

And the very top of the heap, as you mentioned, is what’s called “spruce pine quartz.” And this is the purest quartz that’s ever been found on Earth. It all comes from this small county in rural North Carolina. And it’s 98%, 99% pure.

IRA FLATOW: Why is that so different? What was going on in the Earth that made it so pure?

VINCE BEISER: It’s basically sort of a series of geological accidents. Back when the tectonic plates were moving around to form North America, you had a plate under the Atlantic Ocean coming into contact with the one that underlies the American continent. And at this particular spot, they run into each other at a particular depth.

About 9 to 15 miles below the ground, they grind against each other and create enormous, enormous heat. And between that heat and the fact that in this particular spot there was very, very little moisture, it created this incredibly, incredibly pure quartz, which over millennia, got lifted up much closer to the surface and is now close enough where we can mine it.

IRA FLATOW: 844-724-8255 if you’d like to talk about sand with the sand man, Vince Beiser, author of The World in a Grain. Now, let’s talk about desert sand, the iconic stuff we see in Lawrence of Arabia in the Sahara. Is that the same kind of sand that we get over here? Is it a different kind of sand? Is it unique?

VINCE BEISER: So again, it is mostly quartz. Sand all over the world differs depending on what the local geology is because basically, it’s all bits of ground down mountains, ultimately. It’s bits of rock that have been worn away by wind and rain over the millennia and then wash down deserts– once upon a time were seabeds or lakebeds a long time ago.

So again, most of the sand that you find in there is quartz. But it’s a mix of whatever else might be in the local geology– feldspar, this, that. But the key thing that’s different about desert sand is the shape.

So desert sand, unfortunately, is completely useless to us as human beings for construction. And the reason for that is it’s been eroded by wind rather than water. So in the desert, those grains tumble and tumble and tumble over thousands of years, getting smashed, just banging full force into each other, which rounds off their corners and their angles and makes it quite a bit rounder and smoother than the sand that you find in the bottom of rivers or the bottom of lakes, which tends to be sharper and more angular.

So that desert sand, ultimately, is too round to stick together to build something out of. It’s like the difference between trying to build something out of a stack of marbles as opposed to a stack of little bricks.

IRA FLATOW: You mentioned all the things that use sand. And one of my favorite topics of discussion about these things is– I’m glad you share it in your book– is concrete. I could talk about concrete forever, as my listeners know, as they yawn as I talk about it. And sand is a major part of concrete, right?

VINCE BEISER: Ira, I am so glad to be talking to one of the only other concrete fans in the world. This stuff is so underappreciated. Like most people, I had never even thought about it before I started doing the research for this book. But concrete is literally the foundation of our modern civilization.

And it’s really nothing but sand and gravel glued together with cement. A lot of people mix up concrete and cement. Cement is this fine powdery stuff that’s basically a glue. You mix up cement plus a whole lot of sand and gravel and let it dry, let it cure. And that gives you concrete.

IRA FLATOW: For all these uses of sand, I noticed from reading your book that people steal it. I had no idea that people steal sand right off a beach.

VINCE BEISER: Yeah, well, so this is the amazing thing. We need sand. Like I said, concrete is the thing that our modern civilization is really made out of, right? Every building, every shopping mall, apartment block being built anywhere around the world is made at least partly out of concrete.

So that’s just huge piles of sand. Thousands of tons of sand go into your average building. Also, all the roads, all the highways that connect all those buildings– also made of thousands and thousands of tons of sand.

So what’s happening is, as the world’s population grows and as more and more people move into cities, there is a huge demand for sand way beyond anything that we’ve ever seen before in human history. And as a result, there’s a black market for the stuff such that, indeed, people are stealing sand from beaches, stripping it out of riverbeds, stripping it from lake bottoms, tearing it up from land sources, and causing a lot of environmental damage in the process.

IRA FLATOW: So it’s like a resource. Like oil and gas, there’s only so much of it out there.

VINCE BEISER: Absolutely. It’s the least appreciated natural resource out there. People think of sand as being infinite. And of course, there’s a lot of it. Like I said, it’s the most abundant thing in the world. But at the end of the day, there’s only a finite. There’s only so much of it.

And we are using it at an unbelievable pace. It’s the resource that we consume the most of after air and water. We use about 50 billion tons of the stuff every year. That’s enough to blanket the entire state of California every single year.

IRA FLATOW: And you said you started after your sand journey because you were investigating the illegal sand trade in India, a sand cartel.

VINCE BEISER: Yeah they call them the “sand mafia” in India, believe it or not, which sounds kind of ridiculous. But in fact, it is deadly serious business in India. And I mean literally deadly.

These are groups of organized criminals who are stealing sand from villages, from fishing areas, and/or just mining sand illegally, digging it up from places that are environmentally protected or that are coastal regions. You’re not allowed to mine it because of all the environmental damage.

But because there’s so much money involved, these criminal gangs have gotten really involved. They’re making a lot of money. And they get away with it by doing the same thing organized crime does everywhere. They pay off judges. They pay off police to leave them alone.

And if you really get in their way, they will kill you. Hundreds of people have been murdered over sand in the last few years, mostly in India, but also in other countries around the world. In Kenya, in Indonesia, a bunch of other places– tremendous violence connected with the sand trade.

IRA FLATOW: How come we don’t hear more about that? It doesn’t get a lot of press.

VINCE BEISER: It doesn’t. I think there’s two reasons for that. One is that most of the really dramatic stuff that’s happening with the black market in sand– the killings and the kidnappings and really severe environmental damage– it’s mostly happening in the developing world.

There is considerable environmental damage that happens here in the US. But really, the worst stuff is happening in the developing world. And unfortunately, these days in particular, the media just doesn’t have a lot of time for stuff that’s happening overseas. That’s number one.

Number two is that it’s a relatively recent thing. It’s really only in about the last 20 years or so with the tremendous economic growth that’s happened in China, in India, in Indonesia, all these places around the world. It’s only recently that there’s been such a spike in the demand for sand that all these problems have really started to become serious.

But I do think that’s changing. I can tell you I get calls all the time now from reporters around the world who are starting to become aware of this issue and starting to look into it.

IRA FLATOW: Is there any way to– a lot of tweets are coming in– any way to recycle concrete, take the sand out, use it again?

VINCE BEISER: So yes, there is, is the good news. The bad news is that it’s not happening very much. And there’s three main reasons for that. One is, yeah, you can smash down concrete, crush it up, and reuse it to a certain extent.

But you can’t use it for everything, because the grains of sand– by the time they’ve been reused from concrete, they also have other stuff on them. They’ve been mixed in with cement and maybe other chemicals. And that makes them unfit for certain purposes.

IRA FLATOW: Vince, hold on for reasons two and three. We have to take a break. Vince Beiser is author of World in a Grain– The Story of Sand and How It Transformed Civilization. It’s a great book here on Science Friday.

We’ll take a break. We’ll come back and take your questions and get back to the other two reason with Vince. Stay with us. We’ll be right back.

This is Science Friday. I’m Ira Flatow. We’re talking all about sand, where it comes from, how we become dependent on it, how much of it we use with journalist Vince Beiser, author of the book The World in a Grain– The Story of Sand and How It Transformed Civilization. And when I rudely interrupted Vince, he was telling us about recycling sand, recycling concrete to bring the sand out of it.

VINCE BEISER: Yeah. So as I was saying, three reasons. We can recycle it. But, A, recycled concrete sand– you can’t use it for everything because of all the chemicals that it’s been mixed with. Number two, it’s quite a bit more expensive to do that than to just harvest fresh natural sand. Imagine all the power, all the energy that it takes to run a machine that can smash concrete down into grains.

But the number three problem with the whole idea of recycling is we don’t actually want to recycle most of our concrete structures. It’s not like a newspaper or a bottle, where it’s designed to be a product that you use once and then throw it away. If you build something out of concrete– you build a hospital or a highway or whatever– it’s meant to stay there for 50, 60, 100 years. So really, that sand, most of the time, is taken permanently out of circulation.

IRA FLATOW: Our number– 844-724-8255. Lots of folks with calls. Let’s see if we can take a few. Mike in Mount Vernon, Washington. Hi, Mike.

MIKE: Hello.

IRA FLATOW: Hey there.

MIKE: Yeah, I just had a question real quick. How does the sand vary from that like in outer space or in Mars, like asteroids? Is it the same thing? Can you use that stuff on Earth? Is it just the same, or is there a difference if you know?

IRA FLATOW: Good question.

VINCE BEISER: Wow, that’s a great question. You know what? I wish I knew. I’m going to have to look into that.

IRA FLATOW: Well, look. Think about sand mining. If sand is so scarce, we go out and pull in an asteroid and get the sand off it or something like that.

Are we in danger, then, of losing glass? You said that the second most common use of sand is for making glass. Let me change that to say is different kind of glass made with different kinds of sand? Or is it all the same sand?

VINCE BEISER: It’s basically a question of purity. Like I said, you need upwards of 95% pure silica sand to make glass. And then for really fine glass, you need to start with stuff that’s even more pure, like the Fontainebleau region in France.

The sand there is very, very pure. It’s, I think, like 97%, 98% pure. And that’s why some of the finest European crystal is made with sand from that region, has been for over 100 years.

As far as I know, we’re not really running short of that stuff. There’s a fair bit of it out there. The real problem is just your garden variety, everyday construction sand, because that is the stuff that we are using just in unbelievable quantities.

IRA FLATOW: Let’s go to John in Iowa. Hi, John. Welcome to Science Friday.

JOHN: Hi, Ira. I have a question for Mr. Beiser. Here in Northwestern Iowa, it was real pretty up in there, called Little Switzerland. There’s a controversy over extensive mining of sand for fracking. I was wondering what was unusual about the sand that they would need it for fracking. And I’ll take my answer on the air. Thank you.

IRA FLATOW: Yeah, thanks.

VINCE BEISER: Yeah. I’m glad you brought that. Up that’s a really interesting subspecies. So for fracking, I assume all your listeners know what fracking is. To do it, as you all probably know, you shoot a high pressure mix of water, chemicals, and sand down to shatter, to fracture, the rock where the oil is that you’re trying to get out.

Now, you need a lot of a very specific kind of sand to do that. It has to be very hard– so again, very high purity– because quartz is extremely, extremely hard because it needs to keep those cracks open against the huge geologic pressure that’s trying to close them back up again.

And it also needs to be round. If you remember, I said most quartz sand is angular. But for fracking, you want it to be round so that those droplets of oil and gas can flow around them easily and get into your well.

Now, it just so happens that there’s a lot of that sand in Western Wisconsin and in Minnesota– and I guess in Iowa, too. I wasn’t actually aware of that. But I did go to Western Wisconsin while I was reporting the book.

And there, there’s a big controversy because the fracking boom in North Dakota and in Texas has created a frack sand mining boom there. And they are ripping up hundreds of acres of forest and farmlands to get at that frack sand, which a lot of people in that region are very unhappy about.

IRA FLATOW: Sand’s also becoming a geopolitical issue, too. You talk about this a little bit. There are countries using it to actually build islands, extend their boundaries, aren’t there?

VINCE BEISER: Absolutely.

IRA FLATOW: Where is that sand coming from? That takes a lot of sand, doesn’t it?

VINCE BEISER: It does take a lot of sand. And most of it comes from the bottom of the ocean. So what’s going on is– the idea of using sand to create new land is actually very old. The Romans did the same thing.

A lot of the riverfront in Manhattan is made from sand and silt dredged up from the bottom of the Hudson River. There are artificial islands. We have Balboa Island in Los Angeles, Treasure Island in San Francisco, also totally artificial.

What’s changed is, just in the last 10, 20 years, technology has moved ahead so much that we now have much bigger, more powerful dredging ships that can pull up way more sand much faster than ever before. So lots and lots of countries are getting into the land building business for two reasons. One is to make money. You’ve probably seen pictures of those crazy palm tree-shaped islands off of Dubai. You know what I’m talking about?

IRA FLATOW: Yeah.

VINCE BEISER: So those are nothing but sand, millions of tons of sand that were sucked up from the bottom of the Persian Gulf and put into place to form beachfront real estate. So where there used to be nothing but open water, now there is billions and billions of dollars worth of land where they’ve built hotels and resorts and luxury housing. So that’s one use.

The much more disturbing use is where countries are using it to literally change their borders to create new national territory. And the number one spot to worry about with this is what’s called the Spratly Islands. These are just a bunch of rocks and reefs way out in the middle of the South China Sea in this very hotly contested strategic shipping lane.

And what’s happened there is China seized control of a bunch of these rocks. And just in the last few years, they’ve built up this enormous dredging fleet, the most powerful dredging fleet in the world, and used it to suck up sand from the bottom of the ocean and pile it up on these rocks and create new islands, which they have turned into military bases.

So China is now able to land bombers and fighter aircraft and port nuclear submarines in these places that used to be just rocks way out in the middle of the ocean. And that’s creating a lot of tension between China and all of its neighbors and also between China and the US.

IRA FLATOW: Are they ripping up all the life that lives down in the ocean by sucking up all the sand?

VINCE BEISER: Yeah. So when you do this kind of thing, it damages the environment in two ways. One is whatever was living in that sand before is now obviously dead and gone. Also, when you suck up that much sand, you stir up a lot of sand and silt and muck, which clouds up the water, which can suffocate fish and coral reefs all around.

Second thing is what you do with that sand. So these Spratly Islands– many of them were active, very vibrant, very rich coral reefs. Those coral reefs have literally been buried. They have just been crushed under the weight of all this sand. It was apparently the most rapid rate of coral reef destruction ever in history when they built these things.

IRA FLATOW: You can read a lot more about sand in Vince’s book, The World in a Grain– The Story of Sand and How It Transformed Civilization. Vince Beiser is author. And if you want to read first a little bit about it, you can get an excerpt from it on our website, sciencefriday.com/beach.

Thank you, Vince. It’s a fascinating book, one of my favorite topics, sand and concrete. Thanks for taking the time to be with me today.

VINCE BEISER: Thanks for having me, Ira. I’ll see you at the concrete fan club convention.