All language subtitles for Modern.Marvels.S23E07.More.Iron.1080p.WEB-DL.DDP2.0.H264-BTN_track3_[eng]

- [Narrator] Its
name equals strength.

[metal clanging]

And it makes up nearly
35% of the Earth.

[atmosphere booming]

- [Louis] When that
dying star exploded,

it blasted all over the galaxy.

- [Narrator] It's an
essential building block

for everything from skyscrapers,

to weapons of war.

It is one of the most
important metals on Earth.

- [Jonathan] The
demand is so great

that we run this
operation 24 hours a day,

7 days a week, 365 days a year.

- [Narrator] It's in our bridges

and in our blood.

You'll never look at
iron the same way again.

[glass shatters]

On "Modern Marvels."
More iron.

[upbeat music]

[cogs cranking]

[water bubbling]

[rock music]
[metal clanging]

Iron, the most abundant
element on Earth,

is the stuff that
civilization is made from.

It's everywhere.

From the indispensable
heart of our buildings,

cars, ships, tools, and weapons.

[guns banging]

But it's also the foundation
of the core of our Earth,

and courses in our very blood.

- Iron's incredibly
important to our survival.

It's part of our entire being.

Without iron,

life as we know it
wouldn't be possible.

- [Narrator] Iron is invaluable

not just because of
its unique strength,

but because extreme heat can
make it surprisingly pliable.

- Iron is one of the
few things on Earth

that can go from
an ore, like this,

through fire and forging,

and become a tool like this

that will last for
generations.

- [Narrator] Iron's muscle

comes from its atom's
superior ability

to share some of its 26
electrons with other iron atoms,

forming a vice-like bond.

There's no limit to the size

of the resulting
lattice structure.

- So that's the secret
of its strength,

because the sharing of
electrons between two iron atoms

is essentially the glue

that holds a piece of
iron metal together.

- [Narrator] As
strong as iron is,

it's easily reshaped,

since temperatures over
2,800 degrees Fahrenheit

enable us to break the
bonds between its electrons

and melt it.

- You can actually
rip apart that glue.

The iron atoms are
all floating around

in a liquid soup of iron atoms.

This is very useful for us
for a number of reasons.

If you want to, you
can pour it into a mold

and essentially cast that iron

into whatever shape
that you want.

[upbeat music]

- [Narrator] Iron
in the form of steel

is the most recycled
material in the world.

[machinery booming]

More than 50 million tons
find new light every year

in the United States alone.

- Iron and steel are
endlessly recyclable,

such that the steel
used in a Model T

could have been
used in an ice box,

could have been used in
a building structure,

then used in the vehicle
you're driving today.

The same iron.

[rock music]

- [Narrator] The Earth's
crust is comprised

of about 5% iron ore.

And miners extract about 3
billion tons of it every year.

This enormous open-pit
mine in Minnesota

lies over one of the
largest deposits of iron ore

in the United States.

[tractor horn beeps]

In 2020, the
Cleveland-Cliffs Company

acquired the ArcelorMittal
Minorca Mine,

which processes nearly 10
million tons of iron ore a year.

- This pit that we're
standing in right now

is about a mile wide by
about 3,000 feet in length.

We mine several
layers of ore here.

We're right now
about 400 feet down

to the bottom of the pit.

Open-pit mining is a
methodology of mining

where you excavate and take
off the stripping materials,

the waste materials
are on top of the ore,

expose the ore,

and essentially in the process

make a giant hole in the ground.

The demand for iron is so great

that we run this
operation 24 hours a day,

7 days a week, 365 days a year.

[rocks rumbling]

- [Narrator] Where did
all this iron come from?

[atmosphere booms]

[gentle music]

Billions of years ago,
long after the Big Bang,

stars created heavy
elements within them,

until the stars
became supernovas.

One in particular
helped create the Earth.

- When that dying star exploded,

it blasted iron and
the other elements

all over its area of the galaxy.

When the Earth first formed,

it was a grand mix of elements.

The remnants of the supernova.

And then as that
stuff segregated out

into various pockets,
the iron, which is very dense,

sunk by and large to the core.

- [Narrator] In fact, 98%
of the Earth's core is iron.

But enormous quantities of iron
stayed on the Earth's crust.

Sometimes in the
form of deposits.

Like a mountain range
full of pure iron

that stood in what
is now Minnesota.

The first rains that fell
on Earth were highly acidic

and dissolved the
iron mountains,

creating an iron-rich ocean.

A few hundred
million years later,

the dissolved iron solidified
and settled to the bottom,

leaving the deposits
we mine today.

- Here in Minnesota, we
believe we have enough iron ore

to last the mining activity
for another hundred years

with the iron that's
currently making ore today.

- [Narrator] The
ore extracted here

is an iron oxide called
magnetite, which is 22% iron.

Until the late 1940s,

American iron miners
dug a richer ore,

called hematite at 65% iron.

[cannon booms]

But the enormous demand for iron

during World War
I and World War II

severely depleted the
nation's hematite resources.

[heroic music]

- This is hematite,

the rock that was initially
mined in Minnesota.

It's red in color because
of the oxidized iron.

It looks much like the rust
you'd find on steel or iron

if it's left to weather.

This is magnetite.

This is what we're mining today.

It's black in color

and has a lower iron
content than hematite.

[suspenseful music]

[van humming]

- 10 seconds 'til main blast.

- [Narrator] Getting
to the magnetite ore

starts with a bang.

[ground booming]

[frantic music]

Then loaders transfer the
blasted ore to production trucks

that haul it away
to be processed.

- This is one of our
production trucks.

It's 24-feet wide by 21-feet
high by 42-feet long.

It can haul 240 tons
of iron ore at a time.

[upbeat music]

The whole process
from the mining

all the way through
to concentration plant

is designed to take these
large pieces of iron ore,

make them smaller and
smaller and smaller

so that we can separate
the iron particles

from the rest of the material.

[frantic music]

- [Narrator] After
crushers and grinders

reduce the iron ore to a powder,

mixers combine it with
water to form a slurry.

The slurry then passes
through magnetic separators.

- The magnetic separators
are large drums

that are 10-feet in
length, 4-feet in diameter,

and contain stationary magnets.

As the drums rotate,

they pick up the magnetic iron
particles that are in the ore

and separate them from the
non-magnetic particles.

- [Narrator] Machines mix
the iron slurry with clay,

which is then molded and baked
at 2,400 degrees Fahrenheit

into convenient,
easy-to-transport,

marble-sized pellets.

[rock music]

- This is what it's all about.

Iron ore pellets that
contain over 60% iron.

This is our final product,
ready for shipment.

- [Narrator] But these little
balls are just the beginning

of iron's journey.

Welcome back to more
iron on "Modern Marvels."

Iron, it's one of the most
abundant elements on Earth.

In North America,

The Great Lakes region is home

to one of the largest
deposits in the world.

This mine in Minnesota alone

produces nearly 10 million
tons of iron ore per year.

[rock music]

98% of this iron will be used
to make steel structures.

From the Golden Gate Bridge,

to stadiums,

to skyscrapers,

they're all made of
iron at their core.

To make steel, iron
must be 100% pure.

Impurities, which include
oxygen, must be stripped away.

Melting the iron is
the key to this trick,

in the intense heat produced
inside a blast furnace.

The furnace burns coke,
a purified form of coal.

- It's called a blast furnace

because the amount of air that
is shoved into the system.

It takes incredible
amounts of air

to get the temperatures
necessary to make steel.

- [Narrator] In
the blast furnace,

carbon from the coke is infused
into the iron to make steel.

Too much carbon will
make it brittle.

So just a small amount, no
more than 2%, is all it takes.

- This is a snapshot
of what iron looks like

on an atomic level.

When you make steel,

you've actually taken the
crystal structure of the iron

and you've crammed a carbon
atom into one of the holes

in the crystal structure.

What this does is
it makes it harder

for you to slide the
iron atoms around

with respect to each other

because you've got this
guy crammed in there.

The presence of
this carbon atom,

a bad fit as it is
between these iron atoms,

is what gives steel
its great strength.

- [Narrator] Adding
other elements or alloys

to this fusion of
iron and carbon

produces a variety of steels
that have different properties.

For decades, the iron
atoms' flexibility

has helped the steel
that surrounds us

to vary greatly in its
strength and pliability.

And now with modern
computer technology,

experts are able to mix
more precise amounts

of alloys to iron,

to produce a new enhanced
generation of steels.

- We call them the new
advanced high-strength steels.

They are five to
six times stronger

than the steels we've
used in the past,

making vehicles lighter,
safer, and more fuel efficient.

- [Narrator] One industry

incorporating these new
advanced high-strength steels

is auto manufacturing.

- The value of these
steels in a crash

is their ability
to absorb energy.

So rather than the passenger
absorbing the energy,

your vehicle structure
takes the energy

and keeps the passengers safe.

[metal crashing]

- [Narrator] The new
steels have proven

their strength and
durability in drop tests,

in which a 400-pound
weight drops from 20 feet

to simulate a 35
mile an hour crash.

- This is the result
of the drop test.

Here is our sample.

With the old steel,
it crushes six inches.

With the new steel,
crushes three inches

because of its
increased strength

and energy absorption
capability.

- [Narrator] If you think adding
strength to this new steel

also means adding weight,

think again.

- Here's an automotive component

made with the old technology.

It weighs 40 pounds.

Conferencing the same structure
with the new technology,

it's considerably
lighter, you can see,

and it weighs 32%
less in weight.

- [Narrator] Since the new
steels are lighter and stronger,

less is needed to meet
crash safety standards.

Today, the typical car body

contains as much as 60% of
the new generation of steel

in its construction.

- They'll be applied to
the rail and to the bumper

for front impact,

and to the safety cage
structure for side impact

and for roof strength,

as well as to the door
beams for side impact.

And for rear impact,

they're applied to the rear
bumper and to the rails.

- [Narrator] Iron
in the form of steel

may save lives on the highway,

but throughout history,

humans have used it
as a crucial component

on the battlefield.

[blast booming]

[army radio chattering]

[valiant music]

In fact, iron and the
development of weaponry

have gone hand in
hand since antiquity.

- Empires that were able to
produce the best iron weapons

were the deadliest armies

and those who were able
to conquer their foes.

- [Narrator] Iron began
revolutionizing warfare

over 3,000 years ago.

- First crude weapons that men
used were made out of stones.

These were replaced by bronze.

But when iron came in,

now you had a weapon
that could be sharpened,

would keep its edge,

and even last for generations.

[gentle music]

- [Narrator] The
first iron weapons

were made with iron
extracted from meteorites.

- It was called
swords in the heavens.

'Cause you could
take meteorite iron,

which was almost pure iron,

and beat out weapons
such as knives or swords.

- [Narrator] Whether
separating iron from meteorites

in that era,

or smelting it from iron ore,

making iron pliable
required extreme heat.

[folk music]

How did the ancients manage it?

Workers built a
mound with a hole,

one to two feet in
diameter at the center.

They lined the hole with
fire-resistant clay or stone.

Next, they placed a layer of
charcoal on top of the clay,

which they ignited.

On top of that, they
set the iron ore.

Earlier bronze and copper had
been smelted the same way,

but smelting iron required
an infusion of air

to make the charcoal burn

at iron's higher
melting temperature.

- With the air coming in,

that kept the heat at
a high enough level.

By heating this up,

the oxygen gets stripped
away from the oxide

and carried away with the
waste gases from the fire.

And that leaves you
with the pure iron.

[metal clanging]

- [Narrator] After
workers smelted the iron,

they formed it into a
bar called wrought iron.

Ancient weapon makers

then literally beat the
wrought iron into shape

in a process called forging.

[fire crackling]

- Okay, the first part of the
process in making the knife

is we're gonna make the handle.

I'm hitting it half on and
half off of the anvil,

and that stretches this
part of the material out

and makes it longer and thinner,

and that'll form our handle.

At forging temperature,
or about 1,900 degrees,

the iron is very pliable

so I can take the hammer

and drive it into
whatever shape I need.

- [Narrator] Ancient blacksmiths

forged spears,
knives, and swords

which were stronger
and more durable

than their bronze and
copper predecessors.

- This piece of iron now,

after we've done
all this work on it,

will last for many generations.

- [Narrator] Iron strength
and durability made it ideal

not only for weaponry, but
also for defensive purposes.

[valiant music]

For centuries,

wrought iron was the go-to
metal for making helmets,

shields, and suits of armor.

- This is very
high-quality iron.

It is made for people

who could afford a full
suit of armor like this.

And we often take years

to produce one suit of
iron armor like this.

- [Narrator] But
then, 600 years ago,

that armor would meet a
new foe on the battlefield.

Welcome back to
"Modern Marvels."

For hundreds of years,

civilizations fought their
battles with swords and shields

forged with wrought iron.

[swords clanging]
[men shouting]

But then iron weapons took
a quantum leap forward,

starting in 16th
century Western Europe.

[gun bangs]

- The first muskets that
were made, we believe,

were made like
small hand cannons

where a sheet of
wrought iron was rolled,

and the edges welded together,

and it was formed on the
end of a pole or a pike.

[intense music]

- [Narrator] The wrought
iron musket barrel

achieved devastating
effects on the battlefield.

[gun bangs]

[somber music]

- In the era of forged
iron barrel muskets,

plate armor didn't
have a chance.

- [Narrator] Beyond the wrought
iron used to make muskets

was cast iron.

This was essentially iron
melted down to a liquid

which was poured into a mold
or cast and then cooled.

- This is an example
of cast iron.

This is all one piece.

The advantage of making
pieces of cast iron this way

is you can make multiple
pieces that are just alike,

and in a very short
period of time.

- [Narrator] But cast iron
has one major problem.

[iron cracks]

It's brittle.

In 1856, British
engineer Henry Bessemer

found a way to make a
stronger form of iron

by combining it with
carbon in a blast furnace

to make steel.

- Now with steel,

you cut it, you could mill it,

you could shape it
in not only a tube,

but also a
breech-loading barrel.

With the addition of
metallic cartridges,

you could make a very successful

not only breech-loading weapon,

but repeating weapon as well.

[gun clicking]

[ocean swishing]

- [Narrator] In 1862,

the Union and the Confederacy
began armoring their warships

during the American Civil War.

- The ironclad ships,

they were made from
sheets of wrought iron.

These sheets were applied
either to a wooden hull ship,

such as the Merrimack,

or the entire ship was made
of sheets of wrought iron

that were riveted
together to form the hull

and a turret on top of the deck,

as in the case of the Monitor.

- [Narrator] In their
one and only battle,

both ships received
dozens of direct hits,

but remained afloat.

In the end, the
battle was a draw.

[marching music]

Iron proved to be
the real winner,

changing naval warfare forever.

By the 20th century,

iron-rich hematite supplied
America's vast steel industry.

In 1915, steel supported
a new mechanized war.

- The tanks of World War
I were known as landships.

Just like the ironclads
of the Civil War

revolutionized naval warfare,

these landships of all steel
revolutionized land warfare.

- [Narrator] The iron
battlefield helmet,

which first appeared
centuries ago,

was reintroduced
during World War I.

This time in the form of steel.

- This is an original
World War I helmet

as worn by the British
and United States troops.

It's made out of
thin sheet steel.

It's been stamped the same
way you would see a car body.

The idea here is not to
protect from bullets.

It is to protect from
iron shell fragments

that have been tossed down
from exploding shells above.

You see, most soldiers

spent four years fighting in
trenches dug in the ground.

- [Narrator] World
War II consumed

nearly the last of
the hematite iron.

[blast booming]

[guns rattling]

[atmosphere booming]

More than 65 million tons of
ore was produced in 1944 alone,

allowing American steel
to rule the battlefield,

the oceans, and even the skies.

- We began to use all
metal airplanes,

instead of those made of wood

with a canvas fabric coating.

Steel began to replace all
other organic materials

for weapons.

- [Narrator] Today, iron is
still the most important metal

in every nation's military

as the principle component
in all forms of steel.

But one configuration
of iron as steel

has proven to be warfare's
most dangerous weapon.

The barrel of a gun.

[gun bangs]

[suspenseful music]

The M16 rifle became the US
Army's standard issue weapon

in the Vietnam era.

It's plastic, aluminum,
and steel construction.

It's designed to be lightweight

and portable in
combat conditions.

But to achieve
pinpoint accuracy,

gunsmiths at Fort Benning,
Georgia, use a heavier steel.

- Getting rid of the plastic,
aluminum, when you can,

you end up with a
much better product.

And adding iron to the rifle

makes it a much better
rifle, a much more accurate,

and much more precise.

[rock music]

- [Narrator] They
beef up the M16 rifle

for the elite Army
Marksmanship Unit.

- Take a standard issue M16,

and we basically rebuild it

starting at one
end to the other.

- [Narrator] The M16
barrel is reinforced

with high-grade chromoly steel.

It's made of over 85% iron

and a critical 1% chromium,

and 0.2% molybdenum.

- Iron is the perfect metal
for making rifle barrels.

Due to the fact it will
withstand high temperature

and pressures exerted
from the bullet,

it will last for a much longer
time than some other metals.

[guns banging]

- [Narrator] With each shot,

the barrel must stand up
to the force of a bullet

speeding 3,000 feet per second

with a pressure of 65,000
pounds per square inch.

The Army fashions the
modified M16 barrel

from a piece of raw stock

called a blank.

- What we're starting with
is a nine-pound rifle blank

to make an M16 barrel.

We have to machine
the exterior profile.

It's gonna end up being
around four pounds,

so we'll take about
half that weight off.

You've got areas that

need to be within
1/10,000 of an inch,

which equates to 1/40

of the thickness of a
sheet of notebook paper.

And those tolerances have
to be extremely tight

for accuracy and reliability.

[upbeat music]

- [Narrator] After rigorous
refinements and inspections,

the modified M16 rifle is ready

to challenge the standard
issue on the firing line.

- This is a standard M16 rifle.

[guns banging]

This is our modified
Marksman M16 rifle,

as you can tell by its
custom-made barrel.

[gun banging]

This target was shot with
a standard M16 rifle,

and it's about a
seven-inch diameter group.

This target was shot with
a modified match M16,

and it's about a
1 1/2 inch group.

[gun bangs]

[ships booming]

- [Narrator] Although it has
been synonymous with war,

iron is invaluable
to modern society.

[upbeat music]

One of iron's most
curious properties

provides the motion that powers
the machines of our world.

It's magnetic.

[electronic music]

- Magnets are so important
to the way the world works.

The forces between magnets,
the attractions and repulsions,

can make things move.

[metal clanging]

- [Narrator] This
is a super magnet

made of iron combined with
a number of other elements,

boron and neodymium.

It is a hundred times stronger

than the magnet on
your refrigerator.

- Super magnets can
be very dangerous.

They exert such enormous
forces on one another,

that if your hand is in
the way when they leap,

you're in trouble.

I've put one super magnet
inside this wine glass,

and I'm gonna bring the other
super magnet up toward it.

[glass shattering]

- [Narrator] This
attractive wonder

is the so-called
permanent magnet,

an iron bearing metal
that retains its magnetism

after the removal of
the magnetic force.

That force can either be
another permanent magnet

or a jolt of electricity.

Another form of magnet,
an electromagnet,

is magnetic only when
energized by electric current.

Combine electricity
with any piece of iron

and you've got an electromagnet.

- This is a piece
of ordinary iron.

It's not magnetic.

It won't pick up
the other bolts.

To make it magnetic,

I'm gonna wrap this
wire around this bar.

Now, when I run electric current
through this coil of wire,

it will turn into a
magnet, an electromagnet.

And now it picks up the iron.

But if I cut the power,

the magnetism goes away.

- [Narrator] This
property is the key

to movement in electric motors
that power our industry.

[electronic music]

An electromagnet
called the armature

revolves between the
north and south poles

of a stationary permanent magnet

called the stator.

The armature rotates
until its north pole

is opposite the south
pole of the stator.

The direction of the
armature's current

is then reversed.

The two south poles
repel each other,

pushing the armature forward.

The current reverses
every half turn,

keeping the armature in motion.

[machinery whirring]

Iron is not only
an integral part

of the machinery
powering our world,

but also a mineral
nutrient within each of us,

crucial to our biology.

- The same iron that everybody
sees around the world

is the same iron within us

as small microscopic particles.

And without this iron,
we will cease to live.

- [Narrator] We help maintain

our body's vital supply of iron

by ingesting iron contained
in meat and from vegetables.

Another source is certain brands

of fortified breakfast cereals,

which contain iron baked
right into the flakes.

- There actually
is a scientific way

of determining the
amount of iron present

in a fortified cereal.

- [Narrator] All it takes

is grinding up the
flakes into a mash

and using a magnetic
stirring bar.

The iron in the cereal is
attracted to the magnetic bar.

Then a quick rinse.

- There's about eight milligrams
of iron present in a bowl.

When you start the day with
a fortified breakfast cereal,

you're actually eating
pure iron filings.

- [Narrator] Whatever its
source, iron's critical mission

is transporting oxygen
through our bodies.

Normally combining iron and
oxygen produces iron oxide,

sometimes known as rust.

Which, no surprise, could
do our bodies great damage.

But iron which exists
in our red blood cells

latches onto oxygen molecules.

So why doesn't it turn to rust?

The body's intriguing solution

is to place the iron in a
cage-like molecule called heme.

- Heme is a beautiful cage
that is made inside our body.

It captures and encloses
the iron in the center

and prevents it
from turning to rust

when it binds to oxygen.

[gentle music]

- [Narrator] The iron and
oxygen inside the heme

attaches to a protein
called globin.

The new molecule, hemoglobin,
travels in the blood,

delivering oxygen
throughout the body.

[upbeat music]

But the genes that control

this iron-dependent
transportation are elusive.

Discovering them is critical,

because estimates are
1.6 billion people,

about 1/4 of the
world's population,

are anemic, lacking sufficient
supplies of iron and heme.

Anemia can weaken the
body's immune system

and trigger life-threatening
infections and diseases.

[stern music]

This microscopic
transparent worm

may be the key to
unlocking the mystery.

70% of its genes are
identical to ours

and, like us, it needs
iron and heme to survive.

- So what we did

was we took a small
amount of iron and heme

and put it on this petri dish

so we can directly look at now

what happens in a
transparent animal

as they're actively feeding
on this iron and heme.

- [Narrator] Dr. Hamza
conducted experiments

that revealed some of
the worms digested iron

less successfully than others.

He went on to identify

the missing or mutated
genes of those worms,

marking a major breakthrough.

- We were ecstatic

because this will now
provide us with a small clue

as to how we transport
iron and heme.

This will provide us
with the missing link

between iron
deficiency and anemia.

[upbeat music]

- [Narrator] With heme, the
body may know how to avoid rust,

but rust is everywhere
in our environment.

Welcome back to
"Modern Marvels."

Iron's hallmark is its strength,

but this indispensable metal
girding modern civilization

has one key weakness.

When exposed to wear, or water,

iron turns to rust.

- We don't like rust because
it weakens our structures,

our buildings, our bridges,

and it's quite a
serious problem.

It's a multi-multimillion
dollar industry

trying to control it,

trying to stop it
from happening.

[electronic music]

- [Narrator] Rust is the
result of a chemical reaction

in which the 26 electrons
within the iron atom,

again, come into play.

Two of those electrons
orbit the nucleus

farther away than the rest.

- These electrons are
sort of like black sheep.

It would make the iron
molecule a lot more stable

if these electrons would
go away, basically.

Oxygen, on the other hand,
needs a couple of electrons,

so it's very eager to take them.

So what happens is they
come together, they combine,

and they form a new
compound called iron oxide.

- [Narrator] And that's
iron's arch enemy.

Rust.

Since the added oxygen makes
the iron oxide molecule larger

than the parent iron molecule,

the rust displaces the iron,

and is clearly visible
on the surface.

- The main things that we can do

to protect surfaces from
rusting are to coat them

and stop the ability
of oxygen and water

to get to the surface
in the first place.

[upbeat music]

- [Narrator] However,
there are some

who don't mind a little rust.

In fact, they want
all they can get.

- We love it.

It's rust is us.

- Rockwood Pigments, now
owned by Venator Corporation,

is a manufacturer
that takes advantage

of iron oxide's
beneficial ability

to color our world.

Nature crafts iron oxide,

the same stuff dug
up by iron miners,

in a variety of earth tones.

Then manufacturers
take iron oxide

derived from leftover iron

and turn it into a
variety of pigments.

- We take forms of iron,
mostly in scrap steel,

and oxidize it in sulfuric acid,

and then control that reaction

to make different
forms of iron oxide.

[upbeat music]

- [Narrator] One
ton of scrap metal

makes a ton and 1/2 of pigment,

because of the extra
oxygen molecule.

Iron oxide arrives

at the Rockwood Pigments
Los Angeles plant every year

in three basic colors.

Red, yellow, and black.

- These are two bulk
sacks of iron oxide.

Each one weighs a ton.

Together, it's as
much as an SUV.

- [Narrator] Various
combinations of

the three pigments
enter a blender

where up to five tons
can mix at one time.

- Our main concern here

is to make sure that all
the red, yellow, and black,

or the combination of pigments,

are mixed together so
that we don't get streaks

in the finished product.

- [Narrator] In the
quality control lab,

workers mix the powdered pigment

with a liquid binder
of clay and water.

This sampled batch is then
compared to the standard color

to ensure consistency.

- This is the standard,
which we know is good.

This is the batch
which we're making.

Obviously we'll be adding
some yellow shade red

and sending it back to
production for a rework.

This is our standard
again, and our batch.

Everything looks good
after adjustment.

Ready to ship to the customer.

- [Narrator] The idea of
using iron oxide as pigment

is as old as history itself.

In fact, it was used
to record history

as far back as 17,000 years ago.

[gentle music]

Today, iron oxide
paintings still endure

in France's renowned
Lascaux cave.

The basic concept endured
for centuries as well.

And late medieval and
Renaissance artists

used iron oxide pigment

for the rich, warm
red and orange colors.

- Everyone from
Michelangelo to da Vinci,

to Rembrandt and beyond,

have used iron oxide pigments.

[machinery whirring]

- [Narrator] However, it turns
out most of those pigments

end up not on a canvas,
but in concrete.

- Most people wouldn't know
that concrete is colored.

For instance, the
floors you walk on,

the concrete block
that are structures,

the pavers that
are in our homes,

roof tile on the top of homes.

All of these are
concrete applications

that have been colored
with iron oxide.

In a year, Rockwood Pigments
makes enough iron oxide

that would color concrete

that could cover
the state of Texas.

- [Narrator] But your
closest encounter

with one of these
iron oxide pigments

comes every time you
open your wallet.

- We make hundreds of
tons of black pigment

that gets used in the
color for the US currency.

This black pigment
is so concentrated,

it makes millions and
millions of bills.

Iron oxide black
is used in the ink

that goes on the dollar bill
because it doesn't fade,

it's lightfast, durable, and
it will last a long time.

[uplifting music]

- [Narrator] Our
money may come and go,

but because of iron,

Honest Abe will never fade.

[orchestral music]

In February, 2021,

NASA achieved an
incredible goal,

when the rover Perseverance
landed on Mars.

Its primary mission
is to determine

if evidence can be found

that life once existed
on the Red Planet.

But for some scientists,

Mars holds another completely
different treasure.

- Mars is covered with rust.

Mars is known as the Red Planet

because of the iron oxides
present in the Martian soil.

- There's probably billions
of tons of iron on Mars

that would satisfy civilization
for hundreds of years,

if not thousands of years.

- [Narrator] - While the
Earth's crust is about 5% iron,

the crust of Mars
contains about 14%.

This vast resource beckons
the futurists and scientists

thinking of ways to mine iron,

should we one day
establish colonies on Mars.

- My role as a geologist
is to find enough minerals

for us to have a
society to live on.

- [Narrator] Some estimate
that within the next 50 years,

human colonies may be
established on Mars,

where mining would be a breeze

compared to the
process on Earth.

- On Earth, for us
to get to the iron,

we have to create these
gigantic open pits

that you see in front of us,

where they go down hundreds of
feet just to get to the iron,

and they cover hundreds of
square miles in the end.

Whereas on Mars,

all of the iron ore is sitting
right on top of the surface.

And although it covers
hundreds of square miles,

we don't have to dig down very
deep, maybe about 18 inches.

So that's a lot different

than what you see
in front of us here.

[intense music]

- [Narrator] The Martian
surface may prove

to be even more
user-friendly than imagined.

The pictures sent back from
various Mars rover missions

suggest that natural processes
have already accomplished

a key part of the mining.

- When the probe landed
on the Mars surface

and started roaming around,

they started noticing all
these little round pellets

and they were wondering,
"What in the world is that?"

And they discovered that they
was actually iron minerals.

- [Narrator] Scientists
believe those pellets

contain amounts of iron
similar to the manmade pellets

that need to be mined, crushed,
and baked here on Earth.

- What's really good about the
iron ore deposits out on Mars

is they're already in pellets

and we can go ahead and put
them in the blast furnace.

[frantic music]

- [Narrator] Martian mining
offers one further advantage

over Earth.

- Gravity on Mars is about
38% of what it is on Earth,

so everything is a lot lighter.

We don't need the
big heavy machinery

because everything
is on the surface.

All we have to do is just
scoop up the iron minerals

and transport the iron
minerals to our community

where we'll convert
it into iron metal.

- [Narrator] The iron mine
would be refined on Mars itself

to help build the infrastructure

of extraterrestrial colonies
on Mars, and beyond.

- So we want to find it on
Mars and use it there.

And once we start
manufacturing the products,

then we can take it into
the other heavenly bodies.

This is like a way station

for our expansion of
our people into space.

[gentle music]

- [Narrator] As rich as the
treasure of iron on Mars is,

the true mother lode
is on asteroids.

Some scientists believe they're
comprised of up to 98% iron.

- And these asteroids are so big

that they actually
have more iron

than we've ever produced
on planet Earth.

[upbeat music]

- [Narrator] Only time will tell

if dreams of mining this
essential metal in the heavens

will come true.

But even if our only source
remains here on Earth,

our need for iron promises
to endure as long as we do.

- We'll always have iron.

Iron will always be a
central part of our lives.

It's part of our structures.

It's part of our motion.

It's part of us.

We'll never be without iron.

[iron clanging]