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These Pools Help Support Half The People On Earth

Derek: The world is full
of mysterious places
you can see from high above
using Google Earth,
but what's really going on
down there, and why?
I'm Derek Muller, a scientist,
educator, and filmmaker,
and I'm going to unearth
the stories
behind these amazing places. Just drop a pin and I'm off. ( mysterious music ) ♪ ♪ I am here in the middle
of the Utah desert surrounded by sandstone cliffs
and red rocks
and this scrub. But that is not
what I'm here for. What I'm looking for should be
right over this ridge. ♪ ♪ There are electric blue ponds in the middle
of the Utah desert.
When I saw them
on Google Earth,
I had so many questions,
like what are they?
Why are they here? And why do these colors
keep changing?
One person thought
this might be
a top-secret NASA experiment, since, after all,
you can see them from space.
Someone else suggested,
"Well, maybe they're just
really large swimming pools."
What are those?
What do you think?
Like a geo kinda thermal thing?
Like a solar thing? Like, they come up
from the ground? It's gotta be some sort of,
you know, science experiment
of some kind.

They sort of look
like rice paddies, 'cause they're on ledges. Derek: The truth is
far more fascinating
than any of those guesses. These technicolor pools are
full of something
that's been prized
throughout human history.
What are they used for and how are they connected
to fireworks,
George Washington, soap,
glass, Gatorade, gunpowder,
a pioneering scientist
named Humphry Davy,
every other person
on the planet,
and lots of money? ( birds crying ) ♪ ♪ The answer begins with a pot
and a hardwood fire.
This is
a 1,500-year-old recipe.
Take some hardwood
and burn it,
not for the heat,
but for the ash.
Put the ash in a pot
and add water.
Now, there are a lot
of different chemical
compounds in there,
but the one I'm after is
water soluble,
so it dissolves. Strain out the solids
and you'll find
the solution is slippery. Put it in a pan
and let the water evaporate
in the sun,
and what you're left with is
this crystalline substance.
All that work for this. It is one of the most
important chemicals
people have been making
for centuries,
and it's called potash because that is
exactly where it comes from.
In 1807, British scientist Humphry Davy
got some damp potash
and put electrodes into it. Then he connected them
up to a battery,
and what he observed was
the formation
of tiny metal globules, and as they burst
through the crust
of the potash,
they spontaneously
caught fire.
Davy had discovered
a new element,
so naturally, he named it
pot-ash-ium.
Potassium. Yes, that is where the name
of the element comes from.

It comes from the potash. ♪ ♪ When you hear
the word potassium, many people think
of bananas or Gatorade, and that's true, these foods are
good sources of potassium, but it's not pure potassium. This is a piece
of pure elemental potassium. It's a metal,
but I can squish it with my fingers. And this had to be created
in a lab because it is so reactive,
it'll react with anything. This piece was kept submerged
under oil so it doesn't react
with the water
in the atmosphere. It's an incredibly
reactive substance, and to demonstrate that,
I'm going to put a piece of it in this water.

I'm gonna weight it down so the potassium doesn't
just sit on the top
but actually will sink down
to the bottom.
Three, two, one. – ( pops )
– Oh, yeah! – ( pops )
– Oh! – ( pops )
– Oh, yeah! I did not expect it to do that. That is awesome! Are you kidding me? Yeah! Of course,
I've seen this demo before,
but never with
such a huge explosion.
( in slow-motion )
Oh, yeah! I think the key was
weighing it down
so it didn't just spark
on the surface.
Potassium reacts with water, forming potassium hydroxide
and hydrogen gas.
It also releases
a lot of heat,
so when the hot hydrogen gas
hits the atmosphere,
it spontaneously combusts. Potassium is so reactive because it has one electron
in its outermost shell,
which is easily removed, and that's why we never find
metallic potassium in nature.
Now, the word potash originally
referred to that stuff which, chemically,
is potassium carbonate, but potash has become
a catchall term referring to lots of
potassium-containing compounds.

So the potash
that Davy was using was actually
potassium hydroxide. And this is not the last time
we're gonna hear from Davy. But why is potash
so important to people?
I'm on the trail of Potash. Look at that. ♪ ♪ All right. This is bacon grease. For centuries,
it was used in making soap.
Take some animal fat,
add potash,
and a chemical reaction
creates a primitive
liquid soap.
And look at that.
This is incredible. ( laughs ) I'm getting
a real lather going here. That's not bad.
Take a look at that. The potash soap
actually worked. Potash was also used
to make glass.
Glass is mostly sand,
silicon dioxide,
but add some potash and you reduce
the melting point.
This makes glass less brittle and easier to work with
in early furnaces.
♪ ♪ ( Western music ) ♪ ♪ If you take
the potash solution
and add bat guano or manure, crystals of a different
potassium compound form:
potassium nitrate,
also called saltpeter,
and it's one
of the core ingredients
in fireworks and gunpowder. ♪ ♪ Get ready.

( laughs )
That was awesome! Saltpeter made from potash
infused gunpowder
in the muskets and cannons of battles fought
in China, Europe,
and the American revolution. ( slow-motion explosion ) Potash was by far
the main chemical product
of the early American colonies and a substantial source
of revenue.
By 1788,
there were 250 potash works
in the state
of Massachusetts alone,
places where wood was burned
on a massive scale
just for its ash. In 1790, the newly-independent
U.S. government issued
its first ever patent. It was for an improved process
for making potash.
The patent office has now
issued over 10 million patents
and the literal first one is
for potash.
It was signed
on July 31, 1790.
Look closely at the signature. It's signed by none other than
President George Washington.
That should give you an idea
of how important potash was.
The demand for potash was
so high
that across Europe
and the eastern U.S.,
forests were decimated. Unfortunately, it required
a huge amount of lumber
to create just
a small quantity of potash.
Then in 1861 in Germany, they started
producing potassium from a different source.

They found it not in plants
or any living organism, but in a rock. This is potassium chloride in its natural mineral form. Now, this also gets
the name potash
even though the name
originally referred to ash
in a pot, potassium carbonate.
It changed everything. Germany established
a near monopoly
in the potash supply.
They had so much of the stuff
that they started looking
for new uses.
Well, they did experiments
sprinkling this stuff
on farmers' fields, finding that this acts
as an excellent fertilizer. That's because potassium, along with nitrogen
and phosphorous,
help crops grow far larger and makes them
more drought-resistant.
The downside was, in 1910, just four year before
the start of World War I,
the Germans cut off
potash exports to the world.
Their preemptive first strike was depriving the world
of potassium,
something countries had
become dependent on
to feed
their growing populations.
The U.S. became so desperate
for other sources of potassium
that in 1911,
Congress appropriated money
to find domestic sources. Sites discovered
near Searles Lake, California,
Carlsbad, New Mexico,
and Moab, Utah,
became potash paydirt. ( inquisitive music ) ♪ ♪ But the potash rocks weren't
on the surface.
They were deep underground, so potash had to be mined out. ♪ ♪ But how did it get here
in the first place?
I'm meeting Mike Coronella, a Moab guide who knows
the history of this area.
♪ ♪ So the layer
that the potash is found in is called
the Paradox Formation, and it was created
by an inland ocean
that kept retreating,
returning,
retreating, and returning. The water would evaporate
and leave behind salt
and other evaporites
like potash.
Salt in the ground is
very much like an air bubble
in water.

Geologically,
it wants to float. It's literally pushing up
against the crust here.
And they used
to harvest it underground like coal, you know? Scraping it out, throwing it
on the narrow-gauge rail up to the surface. But salt also likes to trap
oil and gas, and there's oil and gas
in this area. And I believe it was 1963, as they were mining the potash,
they hit a pocket of gas and there was a big explosion,
major loss of life.

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