This is 99% invisible. I'm Roman Mars.

Today's show is about something so tiny and unremarkable and ubiquitous that I can't quite believe we're doing a whole episode about it.

It's sand. The tiny grains of a rotted rock that we sculpt into castles at the beach.

Sand might not seem like a topic worthy of our attention, but Vince Buyser wrote a whole book about sand

it's called The World in a Grain and I promise you it is fascinating. Here's my conversation with Vince, all about sand and how it transformed our civilization.

You know when you were spending a few years on this I imagine you told someone you were working on a book about sand.

What was the look on their face and how did you explain this to them to make them understand how cool and important this subject is?

So every single time I would get this look that was just like, huh? Like why am I trapped?

You know why am I trapped in a conversation with this person who's obsessed with the most boring thing on earth?

And basically my comeback was why would I write a book about what sounds like the most boring thing in the world?

And the reason is because sand is actually the most important solid substance on earth.

It's the literal foundation of modern civilization.

Yeah.

And so how do we use sand in our daily lives?

So basically if you look around you right now, I don't know where you are, but chances are excellent no matter what kind of building or office or room you're sitting in,

the floor underneath you, the walls around the ceiling overhead, the building you're sitting in is probably made at least partly out of concrete.

Just like every shopping mall, every apartment building, every office tower, everywhere in the world from Beijing to Lagos is made out of concrete.

And what is concrete?

Concrete is nothing but sand and gravel that's been stuck together.

The roads that connect all those buildings also made out of sand.

They're either concrete or they're asphalt asphalt is also just sand that's been glued together.

The windows in every one of those buildings are made of sand.

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