at times, even glowing.

How can one not fall in love with rocks and minerals?

I mean, the colors, the shapes...

...and they're the building blocks of modern civilization.

We wouldn't have televisions, we wouldn't have automobiles, we wouldn't have

buildings without the mineral riches that we have.

But could rocks and minerals also solve

the greatest mystery of all time?

The origin of life.

The rocks we pick up tell a story

that life couldn't have occurred without rocks.

Could cold, lifeless stone hold the key

to every living thing on Earth?

From Australia, to Morocco,

Nova goes around the world and back in time

to investigate the origin and evolution of life.

Look at a rock and you think ah, well, nothing.

but this holds the signature of life.

From its first spark...

People were saying they've made Frankenstein in a test tube...

...To the survival of the fittest.

These were immense creatures. Sharks that may have been 50 or 60 feet.

Was it the secret link between rocks and life

that made the difference?

Life's rocky start. Right now, on Nova.

The ancient market of Marrakech,

a chaotic, colorful gathering place teeming with life for thousands of years,

the perfect place to ask how did this exotic, beautiful and sometimes bizarre

thing called life, begin?

How did Earth go from a lifeless, molten rock...

to a living planet?

Full of diverse and spectacular creatures.

it's a question that has long perplexed scientists.

Now, Robert Hazen, a geologist, is trying to show we are missing an essential

ingredient in the recipe for life.

-look at that vein of calcite...

Rocks.

Nothing seems more lifeless than a rock.

it's inanimate, it's the antithesis of a living thing, but we're beginning to

realize that rocks played an absolutely fundamental role in the origin of life.

Hazen is out to expose a secret relationship between rocks and life that

helped drive both the origin of life and its evolution into complex creatures.

This is a very new set of understandings and the more we look, the more we see

that life depends on rocks, rocks depend on life.

This has been going on for four billion years.

As a geologist, it's no surprise

that Hazen is searching for answers written in stone.

But is he right?

Are rocks the missing spark of life?

The history of Earth is unimaginably long.

If it were sped up to the equivalent of a single day, all of humankind from the

earliest skeletons to the invention of the iphone would have occurred in only

the last four seconds.

Dinosaurs were still roaming earth about 20 minutes before that,

but the creation of our planet occurred more than 23 hours earlier, two cycles on

this clock

or 4.5 billion years ago.

Comprehending Earth's vast history is a formidable task.

It is four and a half billion years of change, but you can divide it into half a dozen ways of

describing Earth through time.

Bob Hazen has come up with another way to visualize Earth's long history that

reveals this special relationship between rocks and life.

He has divided it into six stages, each represented by a different color

to understand how we ended up with green earth, the planet we now know, requires us

to turn the clock back to before there was any life at all.

Stage one was the creation of black Earth.

Back in Morocco, Hazen and Adam Aaronson, a meteorite expert, seek out a small rock

from the beginning of our cosmos.

-Wow look at this pile here. -yeah.

These are meteorites. Rocks that have fallen from space.

-This is Tamta. This is the one that fell 20 kilometers up the road from here.

People saw it fall.

A recent meteorite fall in Siberia was captured in videos that have shown up on Youtube.

Other space rocks have ended up for sale here in Morocco.

-Say you'd buy this without doing tests...

-I'll drop the cash right now here and give me a good price.

Meteorites here can sell

for tens of thousands of dollars. That may seem a steep price for a lump of

rock, but these are some of the very oldest objects in our solar system.

This is the oldest object you could ever hold in your hand. It's 4.6 billion years

old and is formed before Earth formed. This is the very first solid material,

the very first rock in our solar system and these came together to build all the planets.

Our Earth was created out of the rocks and dust present at the start of our solar system.

Over time, small fragments of orbiting rock collided, coming together into the

planet circling the Sun.

At first, Earth was molten with temperatures in the thousands of degrees,

but in the cold vacuum of space this hot rock began to cool and change.

Nothing.

Not a speck of dust is believed to have survived from the period of black Earth.

It was a hellishly unpleasant time.

Volcanoes spewed hot lava from deep inside the planet.

When it cooled, it covered Earth with its first rock called basalt

and it was black.

It seems like a desolate landscape, but some ingredients that life will need are

already here in these rocks.

Look inside and you begin to understand how intriguing

even an ordinary rock is.

Every rock, you slice it open

you look inside, there's something special. Rocks are made up mostly of

minerals, which are crystals like quartz or diamonds. Looking through a microscope

at super thin slices of a rock lets you see its mineral composition.

This is the rock Peridotite, made up of small crystals, including olivine and pyroxene.

Even a simple black basalt rock, spewed from a volcano, becomes a

patchwork of colorful minerals.

It's sort of like a fruitcake, you know I slice it open, there's nuts and there's

dried fruit and maybe some lemon peel.

It's made of lots of little things and it is not until you slice into that fruitcake

that you see all the stuff inside that makes it special.

What makes them special is not only their beauty. Minerals have remarkable

chemical and physical properties and are a source of many of the elements -

nature's building blocks.

That is why they are essential in our modern world to make everything from

skyscrapers taller

- mobile phones smaller.

Extract the element molybdenum from the mineral molybdenite to make steel stronger.

Or add a pinch of cobalt and your iphone battery will last longer.

Minerals are the fundamental building block of societies. We wouldn't have

televisions, we wouldn't have automobiles, we wouldn't have buildings without the

mineral riches that we have.

So, were the remarkable chemical properties of minerals also key in

creating life?

If so, Earth would mean more than it started with

It's estimated that the meteorites that formed Earth had only about 250 minerals,

sort of a chemical starter kit, containing many of the elements.

Then, in the intense heat and pressures in the creation of our planet, new

minerals began to form. This changed the appearance of our Earth from black to

gray.

Yosemite national park is a relatively new piece of Earth,

but the kind of rock that makes up these dramatic cliffs goes back much further.

These huge walls are granite containing minerals like quartz and feldspar.

Granite became the foundation of our continents, leading Earth into the gray period.

At this point, earth is still a long way from the glorious diversity of plants

and animals that makes Yosemite so picturesque.

But the stage is set for the next character in our planet story:

Water, which will turn Earth blue. Water plays a central role in every model for

the origin of life.

That's because water is such a great solvent. All these different kinds of

molecules can be floating around the water and then they have the potential to

interact together. The starting point is the water.

So when did Earth cool enough to have liquid water,

this element key to life?

One of the biggest unknowns in this whole idea of going from black to gray

to a blue water-covered earth, is how quickly it happened.

The timing is a big mystery.

The Pilbara in Western Australia is one of the oldest places on Earth

and so, one of the best places to solve the mystery of the planet's first oceans.

Hazen joins an all-star team of geologists, including Martin Van Kranendonk

from the University of New South Wales and John Valley of the University

of Wisconsin.

Valley is collecting rocks that could hold clues to when water first appeared.

We could get zircons and other minerals that date all the way back to

4.4 billion years old.

Hopefully.

Some rocks here contain sand-sized grains that wheathered from even older rocks.

one in a million, literally, is a crystal called zircon, one of the longest lasting

materials in nature.

Zircon is a popular gemstone, but the microscopic zircon found here is even

more precious.

Zircon crystals are especially amazing. Gemstone zircons of course are valued, but

these tiny ones the geologists value are microscopic that make a lousy ring, but

they tell an incredible story.

To tell that story, John Valley must first find the tiny crystals,

the ultimate needle in a haystack.

If you want to find a needle in a haystack, the first thing you do is you

burn down the haystack.

Then you sip through the ash to look for the needle. Rocks are pulverized into

sand sized grains and sorted by weight in a machine developed to pan for gold.

The gold that Valley is looking for are heavy zircon crystals which get

channeled into different tracks.

Then, grain by grain, with a very steady hand,

thousands of small crystals are sorted and analyzed.

The chemical structure of a zircon crystal holds evidence of both the environment

and the age when it formed.

Some of these tiny crystals go very far back,

just over a hundred million years after Earth formed.

They are the oldest pieces of Earth ever discovered.

So they could shed light on what our young planet looked like.

It's totally amazing. To hold this grain of sand in the palm of your hand

is literally to see back through time.

It is a time machine.

Valley expected these crystal time machines would confirm the long-held

view that the young Earth was covered in molten lava, still cooling after its

violent formation.

I think the zircon on the left looks very promising.

So what he discovered was shocking, because this type of zircon created 4.3

billion years ago could only have formed in the presence of liquid water.

But how could there be water if Earth was still hot and hell-like?

The implications were that the early Earth had water,

it was cooler and it was wet.

It's starting to look very much more familiar.

And if water is a key starting point for life

could there be life that early too?

The science of the zircon is telling us that the Earth for a very, very long time

was a habitable environment, not necessarily that there was life then.

We don't know that yet, but there's no reason why there couldn't have been life

as early as 4.3 billion years ago.

So, if life were possible that early, it begs the question: how did life begin?

In 1871, Charles Darwin speculated in a letter to a friend that a warm little

pond might be life's birthplace.

A warm soup of chemicals bathed by energy from the Sun would have been, well,

comfortable for molecules to come together in new ways and create life.

Darwin was way, way ahead of his time.

A nice little warm soup is gonna get you a long way.

Jeff Boda of the Scripps Institution of Oceanography in San Diego has spent his

career working to understand the early Earth's soup of chemicals.

He began under the direction of perhaps the most famous scientist in origin of

life research,

Stanley Miller.

There are in the history of science turning points where we suddenly see the

history of Earth and life differently. In the early nineteen fifties, Stanley

Miller, the eager graduate student, and Harold Urey, the Nobel Prize winning

mentor at the University of Chicago conducted this astonishing experiment

where they made an early Earth environment.

It looks like this sort of a Frankenstein type apparatus, but actually

it's a very carefully thought out design. Boda sets up a modern-day test of the

nineteen fifties experiment on Miller's original lab equipment.

One flask contains water. That's to simulate the ocean.

The other flask has just got the gases in it, so this is the atmosphere.

Just as it does in nature, water from the ocean evaporates and rises into the

atmosphere, where it condenses and returns to the ocean.

Miller simulated what he believed to be the atmosphere of early Earth with

different gases like ammonia and methane.

Then he added a spark of genius.

Miller and Urey decided to use a spark to simulate lightning, because that's

such a ubiquitous process in the atmosphere of the Earth.

That was the real inspiration. These little electric sparks that acted like

simulated lightning. The energy from the spark of lightning breaks down the gas

and water molecules so they can undergo further chemical reactions.

To their astonishment, when they turn this apparatus on, after only a couple of days,

you started seeing this pink color developing.

In a few more days, black

oily goo is forming around the electrodes.

The electrodes get covered with new substances.

Organic compounds, usually associated with life.

And it wasn't just any organic compound. It was amino acids that make proteins,

the ingredients for life.

Amino acids are the building blocks of life.

They form proteins, which are the key component of muscles and other tissues.