Up in the mountains of northern Afghanistan, about seven hours from Kabul, there is a mine

that is one of the oldest in the world,

and one of the most famous.

When Marco Polo visited the mine in the year 1271,

he wrote that this is the place, quote, out of which the best and finest blue is mined.

The mine is called Tsar Isang, and nearly all the world's lapis lazuli comes from it.

Lapis lazuli is a rock that looks kind of like the night sky. It's blue with ribbons of white

and glimmering specks of gold. And when this rock is transformed into pigment through a long

labor-intensive process,

it becomes the most valuable shade of blue on earth, ultramarine.

I'm Kelly McEvers, and this is Atlas Obscura,

a celebration of the world's strange, incredible, and wondrous places.

Color feels like an abstract thing. But really, color is a pigment,

and pigments come from places, places like the Sari Sang minds. Color is often a physical

product of our world. So today we will hear the stories of two colors and how they came to be.

First, ultramarine, an exquisite, extremely expensive shade of blue that totally upended the

Western art world.

And then a shade of purple that likely wouldn't have ever existed in a different place in time.

Cassia St. Clair is the author of The Secret Lives of Color. It is a great book that tells the

stories behind 75 colors, and she's with me today. Hi, Cassia. Hello, thank you so much for

having me. Yeah, thanks for being with us. In your book, you write that color is fundamental to our experience of the world around us. Can you talk about what you mean by that? Sure. So we are a very kind of color sensitive species. We like to organize ourselves around color. So obviously, I'm British, if you can't tell

from my accent, and football, you know, soccer is a religion here. And people care about the

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