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WWW.MY-SUBS.CO

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>> Earth, a unique planet,

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restless and dynamic.

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Continents shift and clash,

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volcanoes erupt,

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glaciers grow and recede--

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titanic forces that are

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constantly at work,

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leaving a trail

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of geological mysteries behind.

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This episode explores

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the incredible journey of

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one of the most indestructible

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and valuable metals

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on the planet--gold.

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Created in outer space,

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an immense explosion

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blasted minute particles of gold

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at 70 million miles per hour

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into the rocks that form

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our planet.

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How tiny pieces of scattered

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gold accumulate to form

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massive deposits is one

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of Earth's great mysteries.

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To find the answer,

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Geological detectives sift

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Through ancient riverbeds,

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Hunting for hidden treasures

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Above and below ground

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And investigating

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Alien natural wonders,

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Finding clues that will

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Ultimately reveal

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"How the Earth Was Made."
S02x13 America's Gold
Original Air Date on March 2, 2010

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-- Sync, corrected by elderman --
-- for <font color=

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>> Gold has mesmerized man

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for thousands of years.

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The oldest known precious metal,

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it plays a powerful role in

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almost every culture on Earth.

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>> Since humans have been

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on this planet,

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gold has been prized.

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It is such a unique mineral.

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It is beautiful.

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You can take an ounce of gold

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and stretch it in a thin string,

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and it'll go for 35 miles.

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>> But the key to gold's

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enduring value is its

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inactivity. It won't bind with

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anything else except itself.

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>> Gold doesn't get used up.

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It gets recycled.

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The ring you're wearing

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may be the exact same gold

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that was in some of the gold

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the pharaohs wore centuries ago.

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With all these properties,

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it's no wonder gold

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has been treasured by man

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down through history.

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>> Man has mined gold

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for thousands of years but found

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only 160,000 tons worldwide,

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enough to fit comfortably

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inside a 4-bed house.

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Physicists discovered

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that this ultimate metal

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was created in outer space long

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before planet Earth existed.

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Over 5 billion years ago,

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gold and other heavy-metal atoms

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formed in the maelstrom

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of a supernova,

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a giant dying star.

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As it exploded, shock waves

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blasted minute gold particles

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across the universe

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at 70 million miles per hour,

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scattering them far and wide

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throughout the early

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Solar System. As this cloud

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of rubble compacted together,

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the gold became trapped

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inside the rocks of the newly

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forming planet Earth.

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Widely dispersed and inactive,

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to this day, most of the Earth's

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gold remains as tiny, isolated

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particles in the rocks.

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>> It's ironic, but gold

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is around us everywhere.

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It's in the soil

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in our backyards.

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It's in these rocks here

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in the riverbeds.

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But the problem is

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it's in very small amounts.

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In these rocks, the gold may be

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at one part per billion.

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That's like finding just a grain

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of sand in an olympic-sized

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swimming pool.

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>> Unusually large stashes

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of gold are concentrated

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in a handful of very special

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places around the world.

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The largest, in southern

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Australia, China,

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South Africa, Peru,

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and the western United States.

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It is the geologists' job to

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find out where and why the Earth

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accumulates gold in large enough

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quantities to mine.

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The first pioneers of gold

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geology were not scientists,

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but gold-hungry prospectors

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who scrutinized the rocks.

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Their story began

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over 150 years ago by accident.

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In 1848, in the small

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Californian town of Coloma,

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along the American River,

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James Marshall was digging

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a trench for a water wheel

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to power his lumber mill when he

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made an extraordinary discovery.

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>> He was digging it down

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during the day and then using

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water at night to flush out

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the sand and gravel,

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and he looked, and there

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on the bedrock were

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a couple of gold nuggets.

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>> Rumors of California's

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River gold spread like wildfire.

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By 1849, over 90,000 people

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from around the world

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descended on the state.

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Nicknamed the Forty-Niners,

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these early investigators

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searched the streams

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in a bid to find their fortune.

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Their first challenge

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was to figure out where gold

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accumulates in the river.

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And they quickly discovered

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that gold wasn't just strewn

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anywhere along its course.

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>> A clue to where the gold

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would be concentrated is

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black sand in areas like this.

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You take a sample

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and pan it out.

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>> The Forty-Niners soon learned

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if they found heavy black sand

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in their pan, they were

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onto a winner.

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>> The process of panning

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is a simple one.

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You're really trying

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to separate light materials

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from heavy material.

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>> In this sluggish water,

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the heavy particles sink

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to the bottom of the pan.

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>> And you repeat the process

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of washing away light materials

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and then concentrating

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the heavies on the bottom

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until you get down

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to just the black sand

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and hopefully some nice gold,

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even a small nugget like that.

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>> IIn the same way,

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rivers and streams

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separate the heavy particles

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from the light.

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The gold and black sand

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are flushed downstream,

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but as they hit the sluggish

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water on the inner bend,

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they drop out of the flow.

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And it's here in the sandbanks

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on the inside bends of the river

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that the Forty-Niners discovered

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an absolute fortune.

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In total, over 20 million ounces

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of river gold were discovered

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in the waterways of California.

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But when they investigated

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the valley sides above

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the river, the Forty-Niners

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discovered an even bigger

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stash of gold.

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>> And they wondered,

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what was the deal with these

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gold deposits that were up

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and away from the water?

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They took a close look at them,

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and they could see that

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these boulders were round

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and smooth.

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>> These rounded boulders

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are identical to those found

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in the rivers nearby.

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>> And the reason is because

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it's an ancient riverbed.

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It's been left high and dry

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by the flow of the river.

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The river cuts downward and

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leaves these deposits behind.

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The miners continued to explore,

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and they found some just above

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the river like this,

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but they found others tens

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and even hundreds,

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even a thousand feet

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above the modern stream.

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>> Using powerful water jets,

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the Forty-Niners blasted

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and flushed out a further

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50 million ounces

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of ancient river gold

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from California's hills,

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which still bear the scars

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over 150 years later.

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Similar river gold deposits

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have formed all over the world,

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including the greatest

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treasure-trove ever found--

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Witwatersrand in South Africa.

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Its discovery in 1886 caused

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another massive gold rush.

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But this river gold is not found

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on the surface.

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Miners must descend over 2 miles

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down the deepest mine shaft

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on Earth.

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>> Half the gold on this planet

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has been produced from that one

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group of deposits.

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Most geologists believe

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that these unique deposits

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formed from ancient river

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systems, concentrating these

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in old river gravels.

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>> Over millions of years,

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thousands of ancient rivers

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carrying gold spilled

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into a huge lake, dumping

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a massive gold deposit.

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This ancient lake bed is now

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buried miles underground.

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To date, Witwatersrand

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has produced over 1.4 billion

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ounces of gold,

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worth over $1.5 trillion.

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And geologists believe

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the same value of gold

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still remains untouched.

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In the search for California's

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River gold, Forty-Niners found

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heavy black sand, a sign

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that gold is deposited

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on the inside bend of a river,

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and gold buried beneath rounded

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boulders in the valley walls,

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proof that rivers have been

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depositing gold for millions

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of years. The Forty-Niners

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suspected that rivers were

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carrying gold down from a source

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somewhere in the mountain,

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the mother lode.

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but the quest to understand

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where this mother lode gold

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originated would take geologists

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deep inside the Earth

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and face to face with some

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of the most destructive powers

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on the planet.

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>> In the 19th century,

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the Forty-Niners plucked

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70 million ounces of river gold

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from California's streams

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and ancient riverbeds,

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valued at more than $80 billion.

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But this easy gold didn't last.

292
00:10:35,301 --> 00:10:36,668
The race was on to find

293
00:10:36,736 --> 00:10:38,770
the source of the river gold,

294
00:10:38,838 --> 00:10:40,205
the mother lode, and they

295
00:10:40,239 --> 00:10:41,840
set off into the mountains

296
00:10:41,908 --> 00:10:43,542
to investigate.

297
00:10:43,610 --> 00:10:44,276
>> And this is what

298
00:10:44,344 --> 00:10:45,177
the old-timers were

299
00:10:45,278 --> 00:10:46,545
really looking for--

300
00:10:46,646 --> 00:10:48,447
A big wide vein of quartz

301
00:10:48,481 --> 00:10:49,915
filled with gold.

302
00:10:49,983 --> 00:10:51,917
It runs literally for miles

303
00:10:51,985 --> 00:10:53,352
through the countryside.

304
00:10:53,353 --> 00:10:54,386
They were able to mine

305
00:10:54,454 --> 00:10:56,021
millions of ounces of gold

306
00:10:56,122 --> 00:10:58,890
from sources just like this.

307
00:10:58,891 --> 00:11:00,258
>> With the discovery

308
00:11:00,293 --> 00:11:01,827
of mother lode gold,

309
00:11:01,894 --> 00:11:03,195
prospecting changed from

310
00:11:03,262 --> 00:11:07,099
a solo quest to big business.

311
00:11:07,200 --> 00:11:08,734
Hundreds of mines sprung up

312
00:11:08,835 --> 00:11:10,168
all over California,

313
00:11:10,203 --> 00:11:14,206
employing thousands of men.

314
00:11:14,273 --> 00:11:15,474
Discovering what geological

315
00:11:15,541 --> 00:11:17,042
force had concentrated gold

316
00:11:17,110 --> 00:11:18,810
in California's mountains was

317
00:11:18,845 --> 00:11:20,112
a puzzle that would bamboozle

318
00:11:20,213 --> 00:11:24,383
scientists for decades.

319
00:11:24,450 --> 00:11:26,652
In 1853, the Alleghany mine

320
00:11:26,719 --> 00:11:28,186
opened in Sierra County,

321
00:11:28,254 --> 00:11:31,423
California. Today, it's over

322
00:11:31,457 --> 00:11:33,825
3,300 feet deep with over

323
00:11:33,926 --> 00:11:36,461
40 miles of tunnels,

324
00:11:36,562 --> 00:11:37,929
all leading to one special

325
00:11:37,997 --> 00:11:40,365
slice of rock in the mountain.

326
00:11:40,433 --> 00:11:42,100
>> Here I am, in the middle

327
00:11:42,201 --> 00:11:44,169
of the mother lode vein.

328
00:11:44,203 --> 00:11:46,004
It must be about 40 feet thick,

329
00:11:46,105 --> 00:11:48,707
and it goes down half a mile

330
00:11:48,741 --> 00:11:51,009
into the Earth.

331
00:11:51,110 --> 00:11:53,111
This is the gold-bearing

332
00:11:53,179 --> 00:11:54,646
quartz vein that the miners

333
00:11:54,747 --> 00:11:57,716
were seeking.

334
00:11:57,750 --> 00:11:59,184
>> Quartz forms from a liquid,

335
00:11:59,285 --> 00:12:00,852
and as it solidifies,

336
00:12:00,920 --> 00:12:03,655
it somehow traps lumps of gold

337
00:12:03,723 --> 00:12:05,924
inside it.

338
00:12:06,025 --> 00:12:08,493
>> It is loaded with gold.

339
00:12:08,494 --> 00:12:10,028
If we break these quartz veins

340
00:12:10,096 --> 00:12:15,567
open, though, we can see...

341
00:12:15,568 --> 00:12:18,003
perhaps small amounts of gold

342
00:12:18,037 --> 00:12:20,205
within the quartz.

343
00:12:20,306 --> 00:12:22,374
This is just an amazing

344
00:12:22,408 --> 00:12:23,842
piece of quartz. You can see

345
00:12:23,943 --> 00:12:25,477
all the free gold in it.

346
00:12:25,545 --> 00:12:28,747
It's just bright and glistens.

347
00:12:28,848 --> 00:12:30,415
There are actually clues

348
00:12:30,483 --> 00:12:32,117
to how the gold got here

349
00:12:32,218 --> 00:12:33,485
within the quartz that was

350
00:12:33,586 --> 00:12:36,455
deposited with the gold.

351
00:12:36,489 --> 00:12:37,689
>> Trapped inside the quartz

352
00:12:37,757 --> 00:12:39,825
are tiny bubbles of fluid.

353
00:12:39,892 --> 00:12:41,059
They are minute remnants of

354
00:12:41,094 --> 00:12:42,894
a stream of water and minerals

355
00:12:42,929 --> 00:12:45,630
that once gushed up this vein.

356
00:12:45,732 --> 00:12:47,265
Analysis of these fluid bubbles

357
00:12:47,366 --> 00:12:48,567
has revealed the extreme

358
00:12:48,634 --> 00:12:49,935
conditions that created

359
00:12:50,002 --> 00:12:52,270
the gold seam.

360
00:12:52,338 --> 00:12:54,106
>> That gold was deposited

361
00:12:54,173 --> 00:12:56,441
at 600 degrees fahrenheit.

362
00:12:56,476 --> 00:12:58,276
It was a very, very hot fluid

363
00:12:58,377 --> 00:13:00,212
that brought the gold

364
00:13:00,279 --> 00:13:03,014
and the quartz to this location

365
00:13:03,082 --> 00:13:07,652
and deposited the vein.

366
00:13:07,754 --> 00:13:09,187
>> But it was a mystery.

367
00:13:09,288 --> 00:13:10,989
What was the driving force

368
00:13:11,023 --> 00:13:13,258
creating all this hot fluid

369
00:13:13,292 --> 00:13:15,193
which carried the gold?

370
00:13:15,294 --> 00:13:16,828
In an old quarry nearby

371
00:13:16,929 --> 00:13:19,030
lies a clue.

372
00:13:19,132 --> 00:13:20,832
The gold-bearing quartz vein,

373
00:13:20,933 --> 00:13:23,401
here stained brown,

374
00:13:23,469 --> 00:13:25,670
is flanked by strange beds

375
00:13:25,772 --> 00:13:28,039
of altered rock.

376
00:13:31,640 --> 00:13:33,240
When the old-timers saw rocks

377
00:13:33,241 --> 00:13:35,041
like this they would get excited.

378
00:13:35,242 --> 00:13:36,942
They knew they were getting close

379
00:13:37,043 --> 00:13:38,643
to the source of the gold.

380
00:13:38,644 --> 00:13:40,244
They would see these rocks

381
00:13:40,245 --> 00:13:41,645
had changed their color.

382
00:13:41,646 --> 00:13:43,046
And then they would get

383
00:13:43,547 --> 00:13:46,247
to the big mother lode quartz vein.

384
00:13:46,248 --> 00:13:48,648
The source of most of the gold ore.

385
00:13:49,793 --> 00:13:52,363
This quartz vein is sandwiched

386
00:13:52,872 --> 00:13:55,075
between these altered rocks.

387
00:13:55,794 --> 00:13:57,061
And looking at these altered

388
00:13:57,129 --> 00:13:58,763
rocks, you see they're

389
00:13:58,797 --> 00:14:01,232
all deformed. They're up on end.

390
00:14:01,333 --> 00:14:02,433
They're sheared up.

391
00:14:02,501 --> 00:14:05,570
They're broken. They're folded.

392
00:14:05,604 --> 00:14:07,038
>> These veins run for hundreds

393
00:14:07,072 --> 00:14:08,606
of miles in a north-south

394
00:14:08,707 --> 00:14:11,609
direction. Similar sandwiches

395
00:14:11,677 --> 00:14:13,711
of gold quartz and broken rock

396
00:14:13,779 --> 00:14:15,346
are found along the entire

397
00:14:15,414 --> 00:14:17,682
length of California,

398
00:14:17,716 --> 00:14:19,784
and strangely, they all run

399
00:14:19,852 --> 00:14:22,053
parallel to the coast.

400
00:14:22,154 --> 00:14:23,221
Whatever immense force

401
00:14:23,255 --> 00:14:24,756
shattered these rocks

402
00:14:24,790 --> 00:14:25,990
must also have created

403
00:14:26,058 --> 00:14:27,792
the hot fluid which carried

404
00:14:27,893 --> 00:14:30,161
and concentrated the gold.

405
00:14:30,229 --> 00:14:33,331
But what was it?

406
00:14:33,399 --> 00:14:34,532
Geologists finally solved

407
00:14:34,633 --> 00:14:36,768
the mystery in the 1950's,

408
00:14:36,802 --> 00:14:38,036
when the revolutionary theory

409
00:14:38,070 --> 00:14:39,771
of plate tectonics shed light

410
00:14:39,872 --> 00:14:41,406
upon how California

411
00:14:41,440 --> 00:14:44,042
and its mountains were made.

412
00:14:44,076 --> 00:14:45,076
They discovered that beneath

413
00:14:45,144 --> 00:14:47,145
the Pacific Ocean, a giant plate

414
00:14:47,179 --> 00:14:48,546
of the Earth's crust moved

415
00:14:48,614 --> 00:14:50,815
eastwards. It plowed into

416
00:14:50,883 --> 00:14:52,417
the American continent,

417
00:14:52,451 --> 00:14:53,618
crumbling huge slabs

418
00:14:53,719 --> 00:14:55,987
of the sea floor as it went.

419
00:14:56,088 --> 00:14:56,955
>> If this big rock

420
00:14:56,989 --> 00:14:58,723
is ancient North America,

421
00:14:58,824 --> 00:15:01,526
over the last 300 million years,

422
00:15:01,594 --> 00:15:03,995
we had a spreading ocean floor

423
00:15:04,063 --> 00:15:06,464
push the ocean and sediments

424
00:15:06,532 --> 00:15:07,999
on top of the ocean

425
00:15:08,067 --> 00:15:09,968
against North America

426
00:15:10,002 --> 00:15:11,703
and stack these pieces

427
00:15:11,770 --> 00:15:13,771
of ocean floor and sediments

428
00:15:13,872 --> 00:15:16,140
on ocean floor up on end

429
00:15:16,208 --> 00:15:19,711
against western North America.

430
00:15:19,778 --> 00:15:20,979
>> California was pushed

431
00:15:21,046 --> 00:15:23,248
above the waves, a mountainous

432
00:15:23,349 --> 00:15:25,216
mass of crushed, crumpled,

433
00:15:25,251 --> 00:15:27,051
and upended rocks separated

434
00:15:27,152 --> 00:15:29,220
by huge cracks running deep

435
00:15:29,255 --> 00:15:30,888
into the crust, creating

436
00:15:30,990 --> 00:15:33,258
a landscape compiled of giant

437
00:15:33,325 --> 00:15:35,059
slabs stacked parallel

438
00:15:35,160 --> 00:15:37,362
to the coast.

439
00:15:37,429 --> 00:15:38,696
This immense mountain-building

440
00:15:38,764 --> 00:15:40,498
process also had the power

441
00:15:40,532 --> 00:15:43,868
to create a piping-hot fluid.

442
00:15:43,902 --> 00:15:46,170
Buried rocks were squashed

443
00:15:46,238 --> 00:15:48,373
under unbearable pressure.

444
00:15:48,407 --> 00:15:49,741
They superheated,

445
00:15:49,775 --> 00:15:51,476
and a 600-degree fluid

446
00:15:51,510 --> 00:15:53,745
was squeezed from them.

447
00:15:53,846 --> 00:15:55,280
Like water running in a river,

448
00:15:55,381 --> 00:15:56,848
this piping-hot fluid

449
00:15:56,915 --> 00:15:58,549
had the ability to concentrate

450
00:15:58,617 --> 00:16:01,653
the scattered gold.

451
00:16:01,754 --> 00:16:03,388
As it washed through the rock,

452
00:16:03,489 --> 00:16:05,356
it leached out minute particles

453
00:16:05,391 --> 00:16:06,557
of gold, creating

454
00:16:06,625 --> 00:16:09,394
a mineral-rich soup.

455
00:16:09,461 --> 00:16:11,362
It poured into the giant cracks,

456
00:16:11,397 --> 00:16:12,397
which pipelined it

457
00:16:12,464 --> 00:16:13,931
to the surface.

458
00:16:13,999 --> 00:16:16,134
As the fluid cooled,

459
00:16:16,201 --> 00:16:17,735
the gold coagulated,

460
00:16:17,770 --> 00:16:19,737
and the quartz crystallized,

461
00:16:19,772 --> 00:16:20,938
forming a solid

462
00:16:21,006 --> 00:16:24,842
gold-bearing quartz vein.

463
00:16:24,910 --> 00:16:27,745
In total, 35 million ounces

464
00:16:27,813 --> 00:16:29,113
of this mountain gold

465
00:16:29,214 --> 00:16:31,949
were blasted out of California,

466
00:16:32,051 --> 00:16:33,184
one of the most profitable

467
00:16:33,218 --> 00:16:36,387
gold-mining areas of its time.

468
00:16:36,488 --> 00:16:38,956
>> Wherever you have oceanic

469
00:16:39,024 --> 00:16:41,192
plates colliding with the edge

470
00:16:41,226 --> 00:16:42,760
of a continent, you're always

471
00:16:42,861 --> 00:16:44,395
going to create fluid,

472
00:16:44,430 --> 00:16:45,663
you're always going to move

473
00:16:45,764 --> 00:16:47,965
those trace amounts of gold,

474
00:16:48,033 --> 00:16:49,834
and that will get focused

475
00:16:49,868 --> 00:16:51,602
into major faults to form

476
00:16:51,670 --> 00:16:53,871
large lode gold deposits.

477
00:16:53,939 --> 00:16:54,739
They're part of

478
00:16:54,773 --> 00:16:57,742
the mountain-building process.

479
00:16:57,776 --> 00:16:59,277
>> Similar gold-bearing quartz

480
00:16:59,378 --> 00:17:01,179
veins lie beneath the coastal

481
00:17:01,213 --> 00:17:02,547
mountains all around

482
00:17:02,581 --> 00:17:04,482
the Pacific rim, where the ocean

483
00:17:04,550 --> 00:17:06,451
floor has crumpled under

484
00:17:06,485 --> 00:17:09,854
gigantic Earth forces.

485
00:17:09,922 --> 00:17:11,923
Scientists investigating

486
00:17:11,990 --> 00:17:13,558
how California's mountain gold

487
00:17:13,625 --> 00:17:15,259
formed have found...

488
00:17:15,294 --> 00:17:17,829
Ancient fluid bubbles,

489
00:17:17,930 --> 00:17:19,564
proof that a hot liquid

490
00:17:19,631 --> 00:17:22,700
deposited the quartz and gold;

491
00:17:22,735 --> 00:17:24,001
Parallel beds of broken,

492
00:17:24,103 --> 00:17:25,737
altered rock, evidence

493
00:17:25,804 --> 00:17:27,271
that the gold-rich fluid

494
00:17:27,339 --> 00:17:28,740
was squeezed from rocks

495
00:17:28,807 --> 00:17:31,876
as mountains formed.

496
00:17:31,910 --> 00:17:34,078
By the 1880's, only 30 years

497
00:17:34,146 --> 00:17:35,980
after the first gold strike,

498
00:17:36,014 --> 00:17:37,715
California's mountain gold

499
00:17:37,783 --> 00:17:39,717
became increasingly difficult

500
00:17:39,785 --> 00:17:42,453
to find. By then, gold hunters

501
00:17:42,521 --> 00:17:43,921
in neighboring Nevada

502
00:17:43,989 --> 00:17:45,456
had stumbled upon an entirely

503
00:17:45,524 --> 00:17:48,359
different type of gold deposit,

504
00:17:48,427 --> 00:17:50,361
but it was the sort of deposit

505
00:17:50,429 --> 00:17:53,264
that could drive men to murder.

506
00:17:55,559 --> 00:17:56,993
>> In the 19th century,

507
00:17:57,061 --> 00:17:58,361
Forty-Niners found

508
00:17:58,429 --> 00:18:02,899
70 million ounces of river gold.

509
00:18:02,967 --> 00:18:04,734
Then they began to ransack

510
00:18:04,802 --> 00:18:06,903
the mother lode, blasting out

511
00:18:06,971 --> 00:18:09,372
over 35 million ounces

512
00:18:09,473 --> 00:18:11,174
of mountain gold,

513
00:18:11,275 --> 00:18:12,475
squeezed from the rocks

514
00:18:12,543 --> 00:18:15,011
as California formed.

515
00:18:15,112 --> 00:18:18,014
[explosion]

516
00:18:18,082 --> 00:18:19,382
For many years, scientists

517
00:18:19,450 --> 00:18:20,917
believed that only the colossal

518
00:18:21,018 --> 00:18:22,719
forces that created mountains

519
00:18:22,753 --> 00:18:24,387
had the power to concentrate

520
00:18:24,455 --> 00:18:25,922
gold scattered throughout

521
00:18:25,990 --> 00:18:29,392
the rocks. But gold strikes

522
00:18:29,460 --> 00:18:31,261
made in neighboring Nevada

523
00:18:31,295 --> 00:18:34,464
were to shatter this theory.

524
00:18:34,531 --> 00:18:36,099
Massive gold veins were found

525
00:18:36,166 --> 00:18:37,734
in the Sagebrush Hills

526
00:18:37,801 --> 00:18:39,836
of the desert. A tidal wave

527
00:18:39,937 --> 00:18:42,372
of gold hunters left California

528
00:18:42,473 --> 00:18:44,474
heading east. The almost

529
00:18:44,541 --> 00:18:46,209
uncharted desolate state

530
00:18:46,277 --> 00:18:47,911
of Nevada began to light up

531
00:18:47,945 --> 00:18:49,646
with life, as gold strikes were

532
00:18:49,747 --> 00:18:53,216
made across the high desert.

533
00:18:53,317 --> 00:18:54,951
This was the gunslinging

534
00:18:55,019 --> 00:18:57,720
Wild West, and the rough

535
00:18:57,755 --> 00:18:59,555
mining town of Bodie had one

536
00:18:59,590 --> 00:19:02,959
of the toughest reputations.

537
00:19:02,960 --> 00:19:04,294
>> It's hard to imagine

538
00:19:04,361 --> 00:19:05,495
more than 8,500 people

539
00:19:05,596 --> 00:19:08,765
up along this stretch here,

540
00:19:08,832 --> 00:19:10,233
lawlessness, lots of fights

541
00:19:10,301 --> 00:19:11,501
breaking out.

542
00:19:11,502 --> 00:19:13,836
[gunshots]

543
00:19:13,871 --> 00:19:17,006
Lots of saloons, opium dens,

544
00:19:17,041 --> 00:19:18,207
and brothels.

545
00:19:18,309 --> 00:19:19,575
>> It was said that a man a day

546
00:19:19,643 --> 00:19:22,211
was killed in Bodie.

547
00:19:22,313 --> 00:19:23,846
[gunshot]

548
00:19:23,881 --> 00:19:26,215
And some historians believe

549
00:19:26,317 --> 00:19:27,750
the fickle geology

550
00:19:27,785 --> 00:19:29,285
of these gold deposits

551
00:19:29,320 --> 00:19:30,420
may have played a part

552
00:19:30,487 --> 00:19:33,222
in this murder rate.

553
00:19:33,324 --> 00:19:34,791
>> Here, the veins were much

554
00:19:34,858 --> 00:19:37,026
more segmented and broken up.

555
00:19:37,061 --> 00:19:38,061
So while one miner

556
00:19:38,128 --> 00:19:39,228
might be mining along

557
00:19:39,296 --> 00:19:41,297
on the vein, another miner

558
00:19:41,332 --> 00:19:43,566
might not be, which would lead

559
00:19:43,600 --> 00:19:45,501
to animosity and tension

560
00:19:45,569 --> 00:19:50,606
and the occasional fight.

561
00:19:50,708 --> 00:19:52,241
>> Geologists realize that,

562
00:19:52,309 --> 00:19:54,510
unlike California's gold seams,

563
00:19:54,611 --> 00:19:57,046
which ran parallel to the coast,

564
00:19:57,147 --> 00:19:58,982
Nevada's were scattered

565
00:19:59,049 --> 00:20:01,851
randomly across the desert.

566
00:20:01,885 --> 00:20:03,219
The hunt was on to understand

567
00:20:03,253 --> 00:20:05,154
why Nevada's gold veins

568
00:20:05,222 --> 00:20:08,891
were so chaotic.

569
00:20:08,959 --> 00:20:10,226
300 miles northeast

570
00:20:10,260 --> 00:20:12,328
of the cramped old mine in Bodie

571
00:20:12,396 --> 00:20:15,631
is the Midas mine.

572
00:20:15,699 --> 00:20:17,433
Large enough to drive

573
00:20:17,534 --> 00:20:18,801
a truck down, it's one

574
00:20:18,902 --> 00:20:20,136
of a handful of remaining

575
00:20:20,170 --> 00:20:22,672
gold quartz mines in Nevada,

576
00:20:22,773 --> 00:20:26,409
and it's a geologist's paradise.

577
00:20:26,510 --> 00:20:27,310
>> It's wonderful to have

578
00:20:27,411 --> 00:20:28,378
an underground mine, because

579
00:20:28,412 --> 00:20:29,312
when you go underground,

580
00:20:29,380 --> 00:20:30,246
you have a 3-dimensional picture

581
00:20:30,314 --> 00:20:31,514
of the geology.

582
00:20:31,582 --> 00:20:32,582
It really helps you get

583
00:20:32,683 --> 00:20:33,916
a feel for what clues

584
00:20:33,984 --> 00:20:35,651
to be looking at that we

585
00:20:35,719 --> 00:20:36,819
might see on the surface

586
00:20:36,920 --> 00:20:37,754
that we might see

587
00:20:37,821 --> 00:20:40,089
better expressed underground.

588
00:20:40,124 --> 00:20:42,892
>> Working mines like Midas have

589
00:20:42,926 --> 00:20:44,827
become geological laboratories

590
00:20:44,895 --> 00:20:46,095
and are helping to unlock

591
00:20:46,196 --> 00:20:47,397
the mystery of Nevada's

592
00:20:47,464 --> 00:20:49,565
scattered gold veins.

593
00:20:53,370 --> 00:20:55,471
Every day, the miners drill

594
00:20:55,539 --> 00:20:56,739
the face and pack it

595
00:20:56,840 --> 00:20:58,541
with explosives, exposing

596
00:20:58,575 --> 00:21:01,744
new networks of quartz veins.

597
00:21:06,245 --> 00:21:07,545
This is just like the old days

598
00:21:07,546 --> 00:21:08,346
but we're high-tech.

599
00:21:08,347 --> 00:21:09,547
They're gonna drill a space out.

600
00:21:09,748 --> 00:21:10,548
Will load it with explosives

601
00:21:10,649 --> 00:21:11,549
and blow it up.

602
00:21:12,967 --> 00:21:14,635
>> 450 pounds of explosives

603
00:21:14,702 --> 00:21:16,436
are about to blow to reveal

604
00:21:16,537 --> 00:21:19,806
the gold-bearing quartz vein.

605
00:21:25,246 --> 00:21:27,247
[explosion]

606
00:21:32,954 --> 00:21:34,521
>> That was great, and to think,

607
00:21:34,589 --> 00:21:35,689
it's so much safer than what the

608
00:21:35,790 --> 00:21:38,692
old-timers had to go through.

609
00:21:38,760 --> 00:21:40,494
>> Once the dust settles,

610
00:21:40,595 --> 00:21:41,795
it's possible to take

611
00:21:41,863 --> 00:21:45,132
a closer look.

612
00:21:45,199 --> 00:21:46,933
>> This is quite a nice big

613
00:21:46,968 --> 00:21:48,702
quartz vein. If I compare

614
00:21:48,770 --> 00:21:49,936
these quartz veins to the veins

615
00:21:49,971 --> 00:21:51,338
that I've seen in California,

616
00:21:51,406 --> 00:21:53,874
they're substantially different.

617
00:21:53,975 --> 00:21:55,409
For one, if I look at these

618
00:21:55,510 --> 00:21:57,411
bands, these dark gray bands

619
00:21:57,445 --> 00:21:59,579
in here.

620
00:21:59,614 --> 00:22:00,714
>> These gray bands are

621
00:22:00,782 --> 00:22:02,149
the first sign that something

622
00:22:02,216 --> 00:22:05,152
very strange has happened here.

623
00:22:05,219 --> 00:22:06,420
>> In a hand sample,

624
00:22:06,521 --> 00:22:07,254
I'll see that there's

625
00:22:07,355 --> 00:22:11,425
lots of gray material.

626
00:22:11,526 --> 00:22:12,626
All that gray material

627
00:22:12,694 --> 00:22:14,528
is silver.

628
00:22:14,595 --> 00:22:15,896
If I look even closer,

629
00:22:15,963 --> 00:22:16,963
I can see little fine flecks

630
00:22:16,998 --> 00:22:19,533
of yellow. That's gold.

631
00:22:19,634 --> 00:22:21,902
The source rock that formed

632
00:22:21,969 --> 00:22:23,270
all of these veins

633
00:22:23,337 --> 00:22:24,271
was much different

634
00:22:24,338 --> 00:22:25,906
than the source rock that caused

635
00:22:25,973 --> 00:22:28,175
the California veins to form.

636
00:22:28,242 --> 00:22:28,975
The California veins

637
00:22:29,077 --> 00:22:30,343
only have gold, and these

638
00:22:30,411 --> 00:22:32,512
are loaded with silver.

639
00:22:32,547 --> 00:22:33,613
>> And the clue to the identity

640
00:22:33,715 --> 00:22:35,348
of the source of Nevada's gold

641
00:22:35,416 --> 00:22:36,416
lies either side

642
00:22:36,451 --> 00:22:38,785
of the quartz vein.

643
00:22:38,820 --> 00:22:40,320
Unlike California, these

644
00:22:40,354 --> 00:22:42,189
wall rocks are not crushed

645
00:22:42,256 --> 00:22:43,423
and have never been

646
00:22:43,458 --> 00:22:45,792
on the ocean floor.

647
00:22:45,827 --> 00:22:46,960
>> This wall rock is

648
00:22:46,994 --> 00:22:48,528
of a volcanic origin,

649
00:22:48,629 --> 00:22:49,463
very similar to, like,

650
00:22:49,530 --> 00:22:50,964
Mount St. Helen's.

651
00:22:50,998 --> 00:22:51,698
>> So it wasn't

652
00:22:51,733 --> 00:22:52,632
mountain-building

653
00:22:52,734 --> 00:22:53,700
that concentrated the gold

654
00:22:53,735 --> 00:22:55,469
and silver in this vein.

655
00:22:55,536 --> 00:22:59,806
It was a volcanic process.

656
00:22:59,841 --> 00:23:01,475
Perhaps the Midas mine

657
00:23:01,542 --> 00:23:04,544
was once a giant volcano.

658
00:23:04,612 --> 00:23:05,545
Geologists went looking

659
00:23:05,613 --> 00:23:07,914
for clues not inside the mine,

660
00:23:07,982 --> 00:23:11,084
but directly above it.

661
00:23:11,119 --> 00:23:11,918
>> Everywhere above

662
00:23:12,019 --> 00:23:12,919
the Midas mine, we see

663
00:23:13,020 --> 00:23:14,354
these strange outcrops.

664
00:23:14,388 --> 00:23:15,255
They're flat on the top

665
00:23:15,289 --> 00:23:16,523
like a table, and if I look

666
00:23:16,557 --> 00:23:18,091
closer, I can see fine

667
00:23:18,192 --> 00:23:20,827
little bands and layers.

668
00:23:20,895 --> 00:23:22,929
>> The outcrop is made of thin

669
00:23:22,997 --> 00:23:27,534
layers less than 1/8" thick.

670
00:23:27,568 --> 00:23:28,668
And there are thousands

671
00:23:28,736 --> 00:23:30,570
stacked on top of each other

672
00:23:30,671 --> 00:23:32,906
like a deck of cards.

673
00:23:32,940 --> 00:23:33,840
>> You've got browns and

674
00:23:33,908 --> 00:23:36,109
yellows, whites, and purples.

675
00:23:36,177 --> 00:23:37,210
Understanding outcrops like this

676
00:23:37,278 --> 00:23:38,445
will help us understand why gold

677
00:23:38,479 --> 00:23:40,180
is deposited at such shallow

678
00:23:40,214 --> 00:23:43,750
depths within the Midas mine.

679
00:23:43,818 --> 00:23:44,851
>> These distinctive

680
00:23:44,919 --> 00:23:46,486
layered rocks are not formed

681
00:23:46,554 --> 00:23:48,655
by a volcano, but another type

682
00:23:48,723 --> 00:23:50,590
of volcanic process that can

683
00:23:50,658 --> 00:23:55,028
still be seen today in Gerlach,

684
00:23:55,096 --> 00:23:57,430
northwest Nevada.

685
00:23:57,498 --> 00:23:59,299
In the middle of the dry

686
00:23:59,367 --> 00:24:01,034
blackrock desert, they found

687
00:24:01,102 --> 00:24:03,670
a mysterious oasis,

688
00:24:03,738 --> 00:24:05,872
and rising out of the landscape

689
00:24:05,940 --> 00:24:07,641
a spectacular multicolored

690
00:24:07,675 --> 00:24:10,143
hot spring, one of over 300

691
00:24:10,211 --> 00:24:12,012
in Nevada.

692
00:24:12,046 --> 00:24:13,947
This bizarre geological wonder

693
00:24:14,048 --> 00:24:17,584
began to form just 45 years ago.

694
00:24:20,421 --> 00:24:21,855
>> Volcanic processes beneath

695
00:24:21,956 --> 00:24:24,057
the Earth heat the groundwater.

696
00:24:24,125 --> 00:24:25,592
It spills out at the surface,

697
00:24:25,660 --> 00:24:27,427
and like a boiling teakettle,

698
00:24:27,495 --> 00:24:31,698
dumps a layer of mineral scale.

699
00:24:31,766 --> 00:24:32,699
>> The water is slowly running

700
00:24:32,767 --> 00:24:33,867
over the tops of these terraces.

701
00:24:33,968 --> 00:24:34,868
It's depositing minerals

702
00:24:34,936 --> 00:24:36,703
in fine little sheets,

703
00:24:36,771 --> 00:24:38,939
kind of like a deck of cards

704
00:24:38,973 --> 00:24:40,774
or a book on end.

705
00:24:40,842 --> 00:24:42,309
This rock, from over there,

706
00:24:42,343 --> 00:24:44,845
has fine laminations or layers.

707
00:24:44,879 --> 00:24:46,780
Rocks like these and terraces

708
00:24:46,848 --> 00:24:48,248
like those are found right above

709
00:24:48,316 --> 00:24:49,883
the Midas mine, which tells me

710
00:24:49,984 --> 00:24:50,884
that Midas was once

711
00:24:50,985 --> 00:24:53,687
an enormous hot spring.

712
00:24:53,788 --> 00:24:55,255
>> Geologists realized it was

713
00:24:55,323 --> 00:24:56,623
hot springs that brought

714
00:24:56,691 --> 00:24:58,792
the gold and silver quartz veins

715
00:24:58,860 --> 00:25:01,394
to the surface in Nevada.

716
00:25:01,429 --> 00:25:02,796
Gold and silver particles

717
00:25:02,864 --> 00:25:04,898
are scattered in molten rocks

718
00:25:04,966 --> 00:25:06,700
deep inside the Earth.

719
00:25:06,767 --> 00:25:08,168
This hot rock released

720
00:25:08,269 --> 00:25:11,071
a gold and silver rich fluid.

721
00:25:11,172 --> 00:25:13,039
As rainwater soaked into

722
00:25:13,074 --> 00:25:14,274
the ground, it reached

723
00:25:14,342 --> 00:25:16,243
the scorching rocks deep

724
00:25:16,344 --> 00:25:17,978
in the crust and superheated

725
00:25:18,079 --> 00:25:21,147
to 900 degrees fahrenheit.

726
00:25:21,182 --> 00:25:22,883
Hot and buoyant, the water began

727
00:25:22,917 --> 00:25:25,185
to rise, sucking up the gold

728
00:25:25,253 --> 00:25:28,121
and silver soup as it went.

729
00:25:28,155 --> 00:25:29,422
As it neared the surface,

730
00:25:29,490 --> 00:25:30,857
the water boiled and dumped

731
00:25:30,925 --> 00:25:32,559
bands of silver and flecks

732
00:25:32,593 --> 00:25:34,694
of gold in the chaotic fractured

733
00:25:34,762 --> 00:25:37,964
pipework of the hot spring.

734
00:25:44,872 --> 00:25:46,139
>> Imagine this landscape

735
00:25:46,207 --> 00:25:48,341
15 million years ago--volcanoes

736
00:25:48,409 --> 00:25:49,776
as far as the eye could see,

737
00:25:49,844 --> 00:25:51,244
hot springs dotting

738
00:25:51,345 --> 00:25:53,947
the landscape here and there.

739
00:25:57,985 --> 00:26:00,987
>> Gold is forming at this

740
00:26:01,055 --> 00:26:02,522
moment in hot springs

741
00:26:02,590 --> 00:26:05,058
all over the world.

742
00:26:05,126 --> 00:26:06,960
Even Yellowstone has traces

743
00:26:06,994 --> 00:26:09,696
of gold in its water.

744
00:26:11,432 --> 00:26:13,533
One of the world's biggest

745
00:26:13,634 --> 00:26:15,602
and most profitable gold mines,

746
00:26:15,636 --> 00:26:17,637
Yanacocha, northern Peru,

747
00:26:17,705 --> 00:26:19,406
is a gold and silver deposit

748
00:26:19,440 --> 00:26:20,640
which man has plundered

749
00:26:20,708 --> 00:26:22,542
since the rule of the Inca

750
00:26:22,610 --> 00:26:25,545
800 years ago.

751
00:26:25,613 --> 00:26:27,814
High in the volcanic Andes,

752
00:26:27,882 --> 00:26:30,884
it's a massive 535 square miles

753
00:26:30,918 --> 00:26:33,353
and has produced over $5 billion

754
00:26:33,454 --> 00:26:35,255
worth of gold, all of it

755
00:26:35,356 --> 00:26:36,623
originating beneath

756
00:26:36,691 --> 00:26:39,592
a bubbling hot spring.

757
00:26:39,694 --> 00:26:40,694
Scientists investigating

758
00:26:40,761 --> 00:26:42,162
how gold-silver veins

759
00:26:42,229 --> 00:26:43,330
formed in Nevada

760
00:26:43,431 --> 00:26:46,333
have found volcanic wall rock,

761
00:26:46,434 --> 00:26:47,701
proof that the gold-rich fluid

762
00:26:47,802 --> 00:26:50,236
came from molten rock,

763
00:26:50,338 --> 00:26:52,072
and a multicolored layered

764
00:26:52,139 --> 00:26:53,873
outcrop, evidence that ancient

765
00:26:53,975 --> 00:26:55,508
hot springs deposited gold

766
00:26:55,609 --> 00:26:57,444
in Nevada.

767
00:26:57,511 --> 00:26:59,245
Nevada's hot-spring gold

768
00:26:59,313 --> 00:27:01,214
deposits yielded over 40 million

769
00:27:01,248 --> 00:27:03,783
ounces of gold and 500 million

770
00:27:03,851 --> 00:27:07,087
ounces of silver, but by 1920,

771
00:27:07,154 --> 00:27:08,621
Nevada's gold seams were

772
00:27:08,723 --> 00:27:10,357
increasingly uneconomical

773
00:27:10,424 --> 00:27:12,058
to mine. The desert became

774
00:27:12,159 --> 00:27:14,327
littered with ghost towns.

775
00:27:14,362 --> 00:27:15,528
It looked like America

776
00:27:15,629 --> 00:27:17,163
had run out of gold.

777
00:27:17,231 --> 00:27:19,366
But in 1961, a new type

778
00:27:19,433 --> 00:27:22,802
of deposit was found.

779
00:27:22,903 --> 00:27:24,137
But it couldn't be seen

780
00:27:24,171 --> 00:27:27,340
or touched. It was invisible.

781
00:27:27,441 --> 00:27:28,775
It would become the biggest

782
00:27:28,809 --> 00:27:30,543
strike in the history

783
00:27:30,611 --> 00:27:32,979
of America's gold.

784
00:27:36,181 --> 00:27:37,248
>> America's gold was

785
00:27:37,282 --> 00:27:38,616
concentrated by incredible

786
00:27:38,650 --> 00:27:40,084
mountain-building forces

787
00:27:40,152 --> 00:27:43,421
that formed California...

788
00:27:43,455 --> 00:27:45,656
and volcanic processes deep

789
00:27:45,724 --> 00:27:48,893
beneath Nevada's hot springs.

790
00:27:48,927 --> 00:27:50,461
But as the deposits

791
00:27:50,529 --> 00:27:51,896
became exhausted,

792
00:27:51,930 --> 00:27:53,364
geologists frantically searched

793
00:27:53,432 --> 00:27:56,200
for new stashes of gold.

794
00:27:56,268 --> 00:28:00,638
Then in 1961, geologist and

795
00:28:00,739 --> 00:28:02,373
gold prospector John Livermore

796
00:28:02,441 --> 00:28:03,741
noticed a suspicious

797
00:28:03,842 --> 00:28:05,276
50-mile-long crack

798
00:28:05,377 --> 00:28:07,011
in the middle of Nevada

799
00:28:07,112 --> 00:28:08,746
called the Carlin Trend

800
00:28:08,847 --> 00:28:12,483
and set out to investigate.

801
00:28:12,551 --> 00:28:13,985
>> John Livermore came to these

802
00:28:14,019 --> 00:28:15,386
hills following up a theory

803
00:28:15,487 --> 00:28:18,222
that gold deposits would be

804
00:28:18,290 --> 00:28:20,658
aligned directly above a deep

805
00:28:20,759 --> 00:28:22,627
crack in the Earth's crust.

806
00:28:22,628 --> 00:28:23,928
He'd come up to outcrops

807
00:28:23,996 --> 00:28:25,930
like this, and he would go ahead

808
00:28:25,998 --> 00:28:29,667
and want to look at them.

809
00:28:29,668 --> 00:28:31,736
>> The rocks are a strange

810
00:28:31,770 --> 00:28:34,472
mixture of mud and quartz,

811
00:28:34,573 --> 00:28:36,274
a mineral created in hot fluid

812
00:28:36,308 --> 00:28:37,842
and a good clue that gold

813
00:28:37,943 --> 00:28:40,745
might be deposited nearby.

814
00:28:40,779 --> 00:28:42,046
>> Based on his experience,

815
00:28:42,114 --> 00:28:43,548
he knew a lot of hot fluid

816
00:28:43,615 --> 00:28:45,283
had come up this crack.

817
00:28:45,317 --> 00:28:46,951
However, he couldn't see

818
00:28:47,019 --> 00:28:48,486
any evidence of gold,

819
00:28:48,587 --> 00:28:49,420
no quartz veins,

820
00:28:49,488 --> 00:28:50,688
no visible gold.

821
00:28:50,756 --> 00:28:52,390
But on a hunch,

822
00:28:52,491 --> 00:28:53,925
he sampled this rock,

823
00:28:53,959 --> 00:28:55,459
took it back to the assay lab

824
00:28:55,494 --> 00:28:56,460
to see if there was

825
00:28:56,495 --> 00:28:58,396
any gold in it.

826
00:28:58,497 --> 00:29:00,498
>> In assay labs,

827
00:29:00,566 --> 00:29:01,499
rocks are crushed

828
00:29:01,567 --> 00:29:02,967
and blasted in a furnace

829
00:29:03,035 --> 00:29:06,037
to over 1,800 degrees.

830
00:29:06,104 --> 00:29:08,506
And as the liquid rock cools,

831
00:29:08,574 --> 00:29:13,611
the minerals begin to separate.

832
00:29:13,679 --> 00:29:15,146
>> At the end of this process,

833
00:29:15,247 --> 00:29:16,314
something extraordinary

834
00:29:16,381 --> 00:29:17,381
has happened.

835
00:29:17,416 --> 00:29:18,416
An ordinary-looking rock

836
00:29:18,483 --> 00:29:19,517
actually contained a grain

837
00:29:19,585 --> 00:29:22,420
of gold at a concentration

838
00:29:22,521 --> 00:29:24,322
of about 5,000 times you would

839
00:29:24,423 --> 00:29:26,224
normally see in the Earth.

840
00:29:26,258 --> 00:29:27,425
It doesn't look like much,

841
00:29:27,526 --> 00:29:29,327
but this is what they mine

842
00:29:29,428 --> 00:29:31,329
every day.

843
00:29:31,430 --> 00:29:33,364
>> Livermore's hunch paid off.

844
00:29:33,432 --> 00:29:36,601
50 miles long and 5 miles wide,

845
00:29:36,668 --> 00:29:38,236
the Carlin Trend is now one

846
00:29:38,337 --> 00:29:40,037
of the largest mining districts

847
00:29:40,072 --> 00:29:41,505
in the world.

848
00:29:41,573 --> 00:29:44,308
This vast man-made pit is big

849
00:29:44,376 --> 00:29:47,144
enough to be seen from space.

850
00:29:49,781 --> 00:29:51,549
>> This is the BetzePpost pit,

851
00:29:51,583 --> 00:29:52,583
one of the world's

852
00:29:52,651 --> 00:29:55,019
largest gold mines.

853
00:29:55,053 --> 00:29:56,487
It contains 45 million ounces

854
00:29:56,555 --> 00:29:59,490
of gold. They have to mine

855
00:29:59,591 --> 00:30:01,592
10 tons of rock in order

856
00:30:01,693 --> 00:30:03,995
to get one ounce out.

857
00:30:04,096 --> 00:30:05,897
As you can see, it's huge--

858
00:30:05,964 --> 00:30:10,701
2 miles long, a mile wide,

859
00:30:10,802 --> 00:30:16,073
2,000 feet deep.

860
00:30:16,174 --> 00:30:18,709
>> Because gold is so valuable,

861
00:30:18,810 --> 00:30:20,344
the extraction of just a few

862
00:30:20,412 --> 00:30:22,246
thousand ounces a day pays

863
00:30:22,347 --> 00:30:23,881
for this extraordinary

864
00:30:23,949 --> 00:30:25,816
mining operation.

865
00:30:25,884 --> 00:30:27,618
And removing the gold ore

866
00:30:27,686 --> 00:30:30,521
requires drastic action.

867
00:30:35,260 --> 00:30:40,865
[explosion]

868
00:30:40,899 --> 00:30:43,901
>> Wow. That's what 400,000

869
00:30:43,969 --> 00:30:46,370
pounds of explosives looks like.

870
00:30:46,438 --> 00:30:48,539
>> Giant diggers work 24 hours

871
00:30:48,607 --> 00:30:50,441
a day excavating over

872
00:30:50,509 --> 00:30:53,377
90 million tons of rock a year,

873
00:30:53,445 --> 00:30:55,079
Enough to cover Central Park

874
00:30:55,147 --> 00:30:58,549
in 55 feet of rubble.

875
00:30:58,650 --> 00:31:00,284
But within this raw gold ore,

876
00:31:00,352 --> 00:31:01,652
not a speck of gold has ever

877
00:31:01,720 --> 00:31:05,656
been seen with the naked eye.

878
00:31:05,724 --> 00:31:06,924
>> The mystery is,

879
00:31:06,992 --> 00:31:08,092
where's the gold?

880
00:31:08,160 --> 00:31:09,093
You can't see it.

881
00:31:09,194 --> 00:31:10,828
The rocks look really ordinary.

882
00:31:10,862 --> 00:31:12,730
The clue to where this gold

883
00:31:12,798 --> 00:31:13,998
is hidden is in the internal

884
00:31:14,099 --> 00:31:15,833
structure of this rock.

885
00:31:15,934 --> 00:31:17,802
>> Magnified 500 times,

886
00:31:17,836 --> 00:31:20,304
the gold is still invisible.

887
00:31:20,372 --> 00:31:21,272
But this rock is

888
00:31:21,373 --> 00:31:22,640
an extraordinary lattice

889
00:31:22,741 --> 00:31:24,709
of quartz and mud perforated

890
00:31:24,743 --> 00:31:26,744
with strange cavities.

891
00:31:26,845 --> 00:31:28,379
>> It looks like a honeycomb,

892
00:31:28,447 --> 00:31:29,580
like something's eaten away

893
00:31:29,648 --> 00:31:32,750
at it. Clearly some strange

894
00:31:32,818 --> 00:31:34,986
geologic process has

895
00:31:35,020 --> 00:31:36,454
concentrated and hidden

896
00:31:36,488 --> 00:31:39,023
the gold in the rock.

897
00:31:39,124 --> 00:31:40,558
>> Scientists realized if they

898
00:31:40,625 --> 00:31:41,759
were going to solve the puzzle

899
00:31:41,860 --> 00:31:43,661
of how gold came to be hiding

900
00:31:43,729 --> 00:31:45,196
in these rocks, first they

901
00:31:45,263 --> 00:31:46,664
would have to understand

902
00:31:46,765 --> 00:31:50,301
where the rocks came from.

903
00:31:50,402 --> 00:31:51,268
A clue was found

904
00:31:51,303 --> 00:31:52,670
in the 19th century by

905
00:31:52,738 --> 00:31:54,905
cattle rancher Absalom Lehman

906
00:31:54,940 --> 00:31:56,307
in the eastern reaches

907
00:31:56,408 --> 00:31:58,409
of Nevada.

908
00:32:06,385 --> 00:32:08,219
>> In 1885, Absalom Lehman

909
00:32:08,320 --> 00:32:09,320
stumbled upon a hole

910
00:32:09,388 --> 00:32:11,922
in the ground, and with rope

911
00:32:11,957 --> 00:32:13,124
and lantern, he lowered himself

912
00:32:13,191 --> 00:32:14,191
in the Earth and discovered

913
00:32:14,226 --> 00:32:16,394
this beautiful cave system

914
00:32:16,495 --> 00:32:17,695
with some of the most

915
00:32:17,763 --> 00:32:19,463
spectacular cave formations

916
00:32:19,498 --> 00:32:24,235
in the world.

917
00:32:24,302 --> 00:32:25,403
>> The solid foundations

918
00:32:25,470 --> 00:32:26,604
of this cave are made

919
00:32:26,671 --> 00:32:28,506
of a messy mixture of mud

920
00:32:28,573 --> 00:32:31,308
and calcium carbonate shells.

921
00:32:31,410 --> 00:32:32,410
They are the remains

922
00:32:32,511 --> 00:32:34,245
of tiny sea creatures,

923
00:32:34,279 --> 00:32:35,513
evidence that Nevada

924
00:32:35,547 --> 00:32:36,714
was once covered

925
00:32:36,815 --> 00:32:39,617
by an ancient tropical sea.

926
00:32:39,718 --> 00:32:40,718
>> For millions and millions

927
00:32:40,786 --> 00:32:43,187
of years, creatures with shells

928
00:32:43,255 --> 00:32:45,790
composed of calcium carbonate

929
00:32:45,824 --> 00:32:47,158
began to rain down through

930
00:32:47,192 --> 00:32:48,325
the ocean and accumulate

931
00:32:48,360 --> 00:32:49,960
on the sea floor forming

932
00:32:49,995 --> 00:32:52,463
this calcareous ooze.

933
00:32:52,531 --> 00:32:55,099
Later, this ooze hardened

934
00:32:55,167 --> 00:32:56,734
into a sedimentary rock

935
00:32:56,835 --> 00:32:59,603
called limestone.

936
00:32:59,638 --> 00:33:00,838
>> These extraordinary

937
00:33:00,906 --> 00:33:02,006
structures in the cave

938
00:33:02,074 --> 00:33:03,908
were formed when water eroded

939
00:33:04,009 --> 00:33:05,810
the huge limestone bed

940
00:33:05,911 --> 00:33:10,081
that sits underneath Nevada.

941
00:33:10,115 --> 00:33:11,248
And back over at the Carlin

942
00:33:11,283 --> 00:33:13,184
Trend, scientists noticed

943
00:33:13,285 --> 00:33:14,618
that the gold ore was made

944
00:33:14,653 --> 00:33:19,924
of a very similar type of rock.

945
00:33:20,025 --> 00:33:21,659
They figured out that

946
00:33:21,726 --> 00:33:23,394
the Lehman Cave limestone

947
00:33:23,462 --> 00:33:25,563
and Carlin Trend gold ore must

948
00:33:25,630 --> 00:33:29,100
once have been the same rock.

949
00:33:29,167 --> 00:33:31,302
>> This is fresh limestone.

950
00:33:31,369 --> 00:33:32,736
This is gold ore.

951
00:33:32,804 --> 00:33:33,737
Clearly something happened

952
00:33:33,839 --> 00:33:35,306
to change this rock into

953
00:33:35,373 --> 00:33:38,476
this spongy gold-bearing ore.

954
00:33:38,543 --> 00:33:39,743
Well, the clue is

955
00:33:39,845 --> 00:33:41,112
in the chemical reactivity

956
00:33:41,213 --> 00:33:44,448
of this limestone.

957
00:33:44,483 --> 00:33:46,851
If I put dilute hydrochloric

958
00:33:46,918 --> 00:33:50,121
acid on this limestone,

959
00:33:50,222 --> 00:33:52,456
note how it fizzes.

960
00:33:52,491 --> 00:33:53,858
Very reactive.

961
00:33:53,925 --> 00:33:55,559
The acid is eating away

962
00:33:55,660 --> 00:33:58,762
at the rock.

963
00:33:58,864 --> 00:34:00,998
Now if I put the acid

964
00:34:01,032 --> 00:34:05,035
on the spongy gold ore...

965
00:34:05,137 --> 00:34:06,403
no reaction. The fluid

966
00:34:06,505 --> 00:34:07,838
is soaking into the rock

967
00:34:07,873 --> 00:34:10,508
like a sponge.

968
00:34:10,575 --> 00:34:11,675
>> Scientists concluded

969
00:34:11,743 --> 00:34:13,577
the reason Carlin Trend gold ore

970
00:34:13,678 --> 00:34:15,146
did not fizz is that

971
00:34:15,213 --> 00:34:16,780
it had already been attacked

972
00:34:16,848 --> 00:34:19,683
by an acid.

973
00:34:19,751 --> 00:34:21,952
Beneath the bed of limestone

974
00:34:22,053 --> 00:34:23,787
at Carlin is a gigantic

975
00:34:23,855 --> 00:34:26,223
vertical crack.

976
00:34:26,324 --> 00:34:27,591
Geologists now believe

977
00:34:27,692 --> 00:34:29,493
that a blast of hot, acidic

978
00:34:29,561 --> 00:34:31,595
gold-rich fluid was once

979
00:34:31,696 --> 00:34:33,130
forced upwards from deep

980
00:34:33,198 --> 00:34:35,699
within the Earth.

981
00:34:35,767 --> 00:34:38,068
It streamed through the crack,

982
00:34:38,136 --> 00:34:40,771
drenching the limestone.

983
00:34:40,839 --> 00:34:42,873
The acid ate into it,

984
00:34:42,974 --> 00:34:44,241
leaving a spongelike

985
00:34:44,309 --> 00:34:47,678
muddy framework behind.

986
00:34:47,712 --> 00:34:49,413
And in the cavities, it dumped

987
00:34:49,481 --> 00:34:51,415
quartz and the most minute

988
00:34:51,483 --> 00:34:54,151
sprinklings of gold.

989
00:34:54,219 --> 00:34:55,619
>> It's only been very recently

990
00:34:55,687 --> 00:34:57,254
that scientists have been able

991
00:34:57,322 --> 00:34:59,156
to use even more sophisticated

992
00:34:59,224 --> 00:35:02,159
imaging equipment--microscopy--

993
00:35:02,260 --> 00:35:04,695
to image down to the scale

994
00:35:04,796 --> 00:35:08,165
of individual atoms.

995
00:35:08,233 --> 00:35:12,169
>> Magnified 100,000 times,

996
00:35:12,270 --> 00:35:14,405
tiny specks of submicroscopic

997
00:35:14,439 --> 00:35:16,273
gold can be seen embedded

998
00:35:16,341 --> 00:35:18,075
in the rock.

999
00:35:18,176 --> 00:35:19,243
Zooming in further

1000
00:35:19,344 --> 00:35:21,812
a staggering 4 million times,

1001
00:35:21,880 --> 00:35:23,080
the gold particle

1002
00:35:23,148 --> 00:35:26,183
Is finally revealed.

1003
00:35:26,251 --> 00:35:27,718
This fleck of gold is only

1004
00:35:27,786 --> 00:35:30,054
5 nanometers in diameter,

1005
00:35:30,088 --> 00:35:31,622
one-millionth the size

1006
00:35:31,723 --> 00:35:34,158
of a pinhead, and each tiny

1007
00:35:34,259 --> 00:35:36,327
white dot is an individual

1008
00:35:36,361 --> 00:35:38,529
gold atom.

1009
00:35:44,903 --> 00:35:46,337
>> These ordinary-looking rocks

1010
00:35:46,371 --> 00:35:48,272
have produced 65 million ounces

1011
00:35:48,373 --> 00:35:50,074
of gold from a single crack

1012
00:35:50,108 --> 00:35:51,075
in the Earth known as

1013
00:35:51,109 --> 00:35:52,509
the Carlin Trend, and it's made

1014
00:35:52,544 --> 00:35:53,811
the United States the fourth

1015
00:35:53,878 --> 00:35:55,179
largest gold producer

1016
00:35:55,247 --> 00:35:56,380
in the world.

1017
00:36:01,984 --> 00:36:03,084
>> Scientists investigating

1018
00:36:03,185 --> 00:36:05,353
how Nevada's gold ore formed

1019
00:36:05,420 --> 00:36:08,356
have found a spongelike

1020
00:36:08,423 --> 00:36:09,891
rock structure, suggesting

1021
00:36:09,925 --> 00:36:11,192
that something ate away

1022
00:36:11,260 --> 00:36:12,994
at the limestone,

1023
00:36:13,095 --> 00:36:14,796
and gold ore not reacting

1024
00:36:14,830 --> 00:36:16,464
with acid, evidence that

1025
00:36:16,565 --> 00:36:18,266
an acidic fluid had already

1026
00:36:18,333 --> 00:36:20,101
attacked the limestone,

1027
00:36:20,169 --> 00:36:21,369
showering it with minute

1028
00:36:21,436 --> 00:36:23,738
particles of gold.

1029
00:36:24,939 --> 00:36:26,739
Similar Carlin type deposits

1030
00:36:26,740 --> 00:36:28,040
have since been discovered

1031
00:36:28,141 --> 00:36:29,241
yielding a further

1032
00:36:29,242 --> 00:36:31,642
35 million ounces of gold.

1033
00:36:32,643 --> 00:36:33,843
Yet these discoveries

1034
00:36:33,844 --> 00:36:36,444
may only be the tip of the iceberg.

1035
00:36:37,524 --> 00:36:39,691
Geologists are now using

1036
00:36:39,726 --> 00:36:41,360
state-of-the-art equipment,

1037
00:36:41,427 --> 00:36:42,628
hoping to unlock millions

1038
00:36:42,729 --> 00:36:44,696
of ounces of American gold

1039
00:36:44,731 --> 00:36:46,532
trapped deep beneath

1040
00:36:46,566 --> 00:36:47,581
the Nevada desert.

1041
00:36:52,087 --> 00:36:53,821
>> Throughout world history,

1042
00:36:53,923 --> 00:36:55,790
over 5 billion ounces of gold

1043
00:36:55,824 --> 00:36:57,926
have been recovered by man,

1044
00:36:57,993 --> 00:36:59,894
and almost 1/10th of this

1045
00:36:59,929 --> 00:37:01,629
has been found in California

1046
00:37:01,664 --> 00:37:03,364
and Nevada, adding up

1047
00:37:03,432 --> 00:37:05,833
to a staggering $280 billion

1048
00:37:05,901 --> 00:37:08,002
worth of bounty.

1049
00:37:08,003 --> 00:37:08,903
>> How much remains

1050
00:37:08,938 --> 00:37:10,271
is anyone's guess.

1051
00:37:10,306 --> 00:37:12,273
There is no reason not to

1052
00:37:12,308 --> 00:37:14,475
assume as much gold exists

1053
00:37:14,577 --> 00:37:16,644
as has been mined in the past.

1054
00:37:16,645 --> 00:37:20,181
But geologists, prospectors,

1055
00:37:20,215 --> 00:37:21,482
explorationists have found

1056
00:37:21,550 --> 00:37:23,751
the easy gold.

1057
00:37:23,852 --> 00:37:25,219
>> In the past, prospectors

1058
00:37:25,287 --> 00:37:26,854
and geologists homed in

1059
00:37:26,922 --> 00:37:28,623
on this easy gold by following

1060
00:37:28,657 --> 00:37:30,758
geological clues exposed

1061
00:37:30,859 --> 00:37:33,861
on the surface.

1062
00:37:33,929 --> 00:37:35,396
But vast areas of Nevada

1063
00:37:35,497 --> 00:37:37,198
are covered in a deep layer

1064
00:37:37,266 --> 00:37:39,000
of mud and gravel that has been

1065
00:37:39,034 --> 00:37:40,401
eroded from the surrounding

1066
00:37:40,469 --> 00:37:43,471
mountains. Geologists believe

1067
00:37:43,572 --> 00:37:45,406
hoards of gold still lie

1068
00:37:45,474 --> 00:37:47,308
concealed beneath this layer

1069
00:37:47,376 --> 00:37:49,577
of gravel, unseen by anyone

1070
00:37:49,678 --> 00:37:52,413
for millions of years.

1071
00:37:52,481 --> 00:37:53,948
Finding all this buried gold

1072
00:37:53,983 --> 00:37:55,316
in an area covering

1073
00:37:55,384 --> 00:37:57,952
110,000 square miles

1074
00:37:58,053 --> 00:38:00,355
is no easy task.

1075
00:38:00,456 --> 00:38:02,357
But one man has the ability

1076
00:38:02,391 --> 00:38:04,459
to see under the ground,

1077
00:38:04,526 --> 00:38:07,128
using pioneering technology.

1078
00:38:10,666 --> 00:38:12,734
>> I've got gold in the hills

1079
00:38:12,835 --> 00:38:15,837
around me.

1080
00:38:15,838 --> 00:38:17,939
I've got good reason to believe

1081
00:38:18,007 --> 00:38:20,742
that there's gold beneath me

1082
00:38:20,843 --> 00:38:23,211
in the rocks, if I could just

1083
00:38:23,278 --> 00:38:25,013
see through this sand

1084
00:38:25,080 --> 00:38:27,215
and gravel.

1085
00:38:27,282 --> 00:38:28,750
This little piece of equipment,

1086
00:38:28,851 --> 00:38:31,019
I believe, is going to help me

1087
00:38:31,086 --> 00:38:33,021
figure that out.

1088
00:38:33,122 --> 00:38:37,125
[machinery whirring]

1089
00:38:37,192 --> 00:38:38,493
>> The geo-probe is drilling

1090
00:38:38,560 --> 00:38:39,994
not for rocks,

1091
00:38:40,029 --> 00:38:41,195
but for groundwater,

1092
00:38:41,230 --> 00:38:43,364
200 feet below the surface,

1093
00:38:43,399 --> 00:38:44,866
and it's this groundwater

1094
00:38:44,933 --> 00:38:46,567
that holds the key to finding

1095
00:38:46,669 --> 00:38:49,137
Nevada's hidden gold.

1096
00:38:49,204 --> 00:38:51,105
>> If there's a gold deposit

1097
00:38:51,140 --> 00:38:52,740
concealed by the sand

1098
00:38:52,775 --> 00:38:54,942
and gravel, the groundwater

1099
00:38:55,010 --> 00:38:57,045
will interact with it,

1100
00:38:57,146 --> 00:38:59,547
and you'll pick up clues.

1101
00:38:59,581 --> 00:39:01,315
>> Traces of metals associated

1102
00:39:01,383 --> 00:39:02,850
with gold seep into

1103
00:39:02,951 --> 00:39:04,686
the groundwater, clues that will

1104
00:39:04,753 --> 00:39:06,421
lead Hodges to the secret

1105
00:39:06,488 --> 00:39:08,222
location of the gold deposit

1106
00:39:08,323 --> 00:39:11,759
deep below the surface.

1107
00:39:11,860 --> 00:39:14,862
>> Imagine an iron bar rusting

1108
00:39:14,930 --> 00:39:17,065
in a bucket of water.

1109
00:39:17,132 --> 00:39:18,466
The trace metals are going to

1110
00:39:18,500 --> 00:39:20,501
come out of that rusted iron bar

1111
00:39:20,602 --> 00:39:21,969
and are going to be disseminated

1112
00:39:22,037 --> 00:39:23,871
in the groundwater, and you

1113
00:39:23,939 --> 00:39:25,206
would be able to sample

1114
00:39:25,240 --> 00:39:27,241
that groundwater and tell

1115
00:39:27,342 --> 00:39:28,676
that there was an iron bar

1116
00:39:28,711 --> 00:39:30,211
somewhere nearby, just as we're

1117
00:39:30,245 --> 00:39:31,212
going to be able to sample

1118
00:39:31,246 --> 00:39:32,613
this groundwater and know that

1119
00:39:32,681 --> 00:39:34,315
there's a gold deposit

1120
00:39:34,349 --> 00:39:35,516
somewhere nearby.

1121
00:39:35,584 --> 00:39:36,517
So in a sense, it's like

1122
00:39:36,618 --> 00:39:38,619
the deposit of gold

1123
00:39:38,687 --> 00:39:41,055
is creating a scent.

1124
00:39:41,156 --> 00:39:42,256
>> If Hodges can latch on

1125
00:39:42,324 --> 00:39:44,859
to a whiff of this scent,

1126
00:39:44,893 --> 00:39:46,127
he can track it back

1127
00:39:46,161 --> 00:39:48,963
to find the gold.

1128
00:39:49,064 --> 00:39:49,897
Once the drill

1129
00:39:49,965 --> 00:39:51,232
is deep enough, Hodges

1130
00:39:51,333 --> 00:39:53,434
pumps out the groundwater.

1131
00:39:53,502 --> 00:39:58,306
[pump whirring]

1132
00:39:58,340 --> 00:40:00,441
>> Ok. I think I've got

1133
00:40:00,542 --> 00:40:02,710
enough sample now.

1134
00:40:02,778 --> 00:40:03,878
Somewhere in this bucket

1135
00:40:03,946 --> 00:40:06,147
of muddy water, I believe

1136
00:40:06,181 --> 00:40:09,083
we've got some clues.

1137
00:40:09,151 --> 00:40:10,451
>> This is no ordinary

1138
00:40:10,519 --> 00:40:11,619
pickup truck.

1139
00:40:11,687 --> 00:40:12,820
It's a state-of-the-art

1140
00:40:12,888 --> 00:40:14,956
mobile laboratory.

1141
00:40:14,990 --> 00:40:16,157
Hodges measures how many

1142
00:40:16,225 --> 00:40:17,158
trace metals are in

1143
00:40:17,226 --> 00:40:18,526
the groundwater,

1144
00:40:18,627 --> 00:40:19,794
and the scent here

1145
00:40:19,828 --> 00:40:22,430
is particularly strong.

1146
00:40:22,464 --> 00:40:23,364
>> And it's telling me

1147
00:40:23,465 --> 00:40:24,532
that I've likely got

1148
00:40:24,600 --> 00:40:27,001
a lot more trace metals.

1149
00:40:27,069 --> 00:40:31,539
Arsenic, antimony, mercury,

1150
00:40:31,640 --> 00:40:33,441
copper, lead, zinc are the kinds

1151
00:40:33,509 --> 00:40:35,009
of trace metals that are often

1152
00:40:35,077 --> 00:40:37,178
associated with gold deposits.

1153
00:40:37,246 --> 00:40:38,446
And it looks to me like we're

1154
00:40:38,547 --> 00:40:42,650
moving in the right direction.

1155
00:40:42,718 --> 00:40:43,718
>> In the same way

1156
00:40:43,819 --> 00:40:45,286
the old-timers traced the gold

1157
00:40:45,354 --> 00:40:46,654
up into the mountains,

1158
00:40:46,722 --> 00:40:48,022
Hodges tracks the increasing

1159
00:40:48,090 --> 00:40:49,924
concentration of trace metals

1160
00:40:49,992 --> 00:40:52,426
in the groundwater.

1161
00:40:52,528 --> 00:40:53,494
>> It's like a little childhood

1162
00:40:53,529 --> 00:40:55,596
game of hide-and-go-seek.

1163
00:40:55,631 --> 00:40:56,497
Am I getting hotter,

1164
00:40:56,532 --> 00:40:58,032
or am I getting colder?

1165
00:40:58,066 --> 00:41:00,768
And that makes it a science.

1166
00:41:00,803 --> 00:41:01,903
>> The net is tightening

1167
00:41:01,970 --> 00:41:03,471
around the gold deposit.

1168
00:41:03,505 --> 00:41:05,139
The scent is strongest in this

1169
00:41:05,207 --> 00:41:08,509
4-square-mile target zone.

1170
00:41:08,577 --> 00:41:10,411
But it's still too large an area

1171
00:41:10,479 --> 00:41:13,581
to begin test-drilling for gold.

1172
00:41:13,682 --> 00:41:14,782
To focus in further,

1173
00:41:14,850 --> 00:41:15,950
Hodges needs to literally

1174
00:41:16,051 --> 00:41:19,954
see inside the Earth.

1175
00:41:20,022 --> 00:41:21,155
>> Well, this instrument here

1176
00:41:21,223 --> 00:41:22,957
is a gravitometer,

1177
00:41:23,025 --> 00:41:24,859
and it has the ability

1178
00:41:24,927 --> 00:41:27,962
to measure how dense the rocks

1179
00:41:27,996 --> 00:41:30,598
are beneath this point.

1180
00:41:30,666 --> 00:41:32,333
Just as there's a landscape

1181
00:41:32,434 --> 00:41:35,937
here on the horizon behind me,

1182
00:41:35,971 --> 00:41:38,406
there's a landscape

1183
00:41:38,440 --> 00:41:41,075
in the bedrock underneath me.

1184
00:41:41,143 --> 00:41:42,143
>> Multiple readings

1185
00:41:42,211 --> 00:41:43,344
from the gravitometer

1186
00:41:43,412 --> 00:41:44,779
create a secret treasure map

1187
00:41:44,847 --> 00:41:46,047
of the terrain submerged

1188
00:41:46,148 --> 00:41:48,249
beneath the surface gravel.

1189
00:41:48,317 --> 00:41:50,117
From this rock density map,

1190
00:41:50,152 --> 00:41:51,986
Hodges can pinpoint the likely

1191
00:41:52,054 --> 00:41:55,223
location of the gold deposit.

1192
00:41:55,257 --> 00:41:56,757
He has found a suspect gas

1193
00:41:56,825 --> 00:41:58,860
in the Earth over a mile long

1194
00:41:58,927 --> 00:42:01,929
and 250 feet below the surface.

1195
00:42:02,030 --> 00:42:03,464
It's a good sign, as gold

1196
00:42:03,498 --> 00:42:05,199
is often found deposited

1197
00:42:05,234 --> 00:42:08,035
in deep cracks. It's time

1198
00:42:08,136 --> 00:42:13,307
to start drilling for gold.

1199
00:42:13,408 --> 00:42:14,775
The diamond-studded drill

1200
00:42:14,877 --> 00:42:16,477
probes the crack and extracts

1201
00:42:16,511 --> 00:42:19,780
a cylinder of bedrock.

1202
00:42:19,848 --> 00:42:21,015
This is the first

1203
00:42:21,049 --> 00:42:22,583
in a sequence of test drills

1204
00:42:22,651 --> 00:42:24,218
along the crack, and the results

1205
00:42:24,286 --> 00:42:26,587
are tantalizing.

1206
00:42:26,688 --> 00:42:27,688
>> After all this traveling

1207
00:42:27,756 --> 00:42:29,056
around, I'm finally able to see

1208
00:42:29,157 --> 00:42:31,592
the rocks for the first time.

1209
00:42:31,660 --> 00:42:32,526
These rocks have been

1210
00:42:32,594 --> 00:42:34,161
out of view for millions

1211
00:42:34,229 --> 00:42:35,563
of years, and to me,

1212
00:42:35,597 --> 00:42:37,031
it's one of the most exciting

1213
00:42:37,065 --> 00:42:39,767
things about this line of work.

1214
00:42:39,801 --> 00:42:40,968
I get to look at these rocks

1215
00:42:41,069 --> 00:42:42,036
before anybody else has ever

1216
00:42:42,070 --> 00:42:43,437
seen them, and I could compare

1217
00:42:43,505 --> 00:42:45,239
them with the rocks that I've

1218
00:42:45,340 --> 00:42:47,775
seen elsewhere in the mountains.

1219
00:42:47,876 --> 00:42:49,610
In this piece of core,

1220
00:42:49,678 --> 00:42:50,845
I see several different kinds

1221
00:42:50,879 --> 00:42:52,413
of fragments of rocks.

1222
00:42:52,514 --> 00:42:53,981
Some of them are quartz.

1223
00:42:54,049 --> 00:42:56,884
Quartz we know is good for gold.

1224
00:42:56,952 --> 00:42:58,352
>> Hodges could be on the verge

1225
00:42:58,420 --> 00:43:00,521
of a massive gold strike,

1226
00:43:00,622 --> 00:43:01,622
adding to his tally

1227
00:43:01,690 --> 00:43:02,857
of 30 million ounces

1228
00:43:02,891 --> 00:43:05,693
discovered so far.

1229
00:43:05,761 --> 00:43:06,994
>> Reaching down into the Earth,

1230
00:43:07,062 --> 00:43:08,162
pulling out a sample that says

1231
00:43:08,263 --> 00:43:10,264
there's gold in it and realizing

1232
00:43:10,332 --> 00:43:12,700
that you've done it.

1233
00:43:12,768 --> 00:43:15,069
And in a sense, it connects you

1234
00:43:15,137 --> 00:43:16,404
with those old-timers,

1235
00:43:16,438 --> 00:43:18,539
the same spirit of the old west.

1236
00:43:18,607 --> 00:43:21,642
It's exciting.

1237
00:43:21,710 --> 00:43:23,044
>> It's pioneering geologists

1238
00:43:23,078 --> 00:43:24,512
like Hodges who will find

1239
00:43:24,546 --> 00:43:29,083
what's left of America's gold.

1240
00:43:29,151 --> 00:43:30,351
Scientists and prospectors

1241
00:43:30,452 --> 00:43:31,519
investigating how gold

1242
00:43:31,553 --> 00:43:33,621
is concentrated around the world

1243
00:43:33,689 --> 00:43:37,458
have found gold in heavy black

1244
00:43:37,526 --> 00:43:39,360
sands, evidence that rivers

1245
00:43:39,461 --> 00:43:41,529
concentrate gold on the inside

1246
00:43:41,563 --> 00:43:43,898
bends...

1247
00:43:43,999 --> 00:43:45,266
Parallel beds of broken,

1248
00:43:45,367 --> 00:43:46,701
altered rock, proof that

1249
00:43:46,735 --> 00:43:48,469
gold-rich fluid was squeezed

1250
00:43:48,537 --> 00:43:51,539
from California's mountains...

1251
00:43:51,640 --> 00:43:54,108
Multicolored layered outcrops

1252
00:43:54,176 --> 00:43:55,643
show that ancient hot springs

1253
00:43:55,711 --> 00:43:57,745
deposited gold quartz veins

1254
00:43:57,813 --> 00:44:00,181
in Nevada...

1255
00:44:00,248 --> 00:44:01,649
And spongy gold ore,

1256
00:44:01,750 --> 00:44:03,284
evidence that an acid dumped

1257
00:44:03,385 --> 00:44:04,885
minute sprinklings of gold

1258
00:44:04,920 --> 00:44:08,923
in the rock.

1259
00:44:09,024 --> 00:44:10,257
The Earth does not relinquish

1260
00:44:10,292 --> 00:44:12,927
her gold treasure easily.

1261
00:44:12,995 --> 00:44:14,662
Man's irresistible urge to find

1262
00:44:14,730 --> 00:44:17,164
gold is the driving force

1263
00:44:17,199 --> 00:44:18,833
which helped pioneer

1264
00:44:18,900 --> 00:44:21,102
the science of geology.

1265
00:44:21,169 --> 00:44:22,370
Investigating how gold is

1266
00:44:22,404 --> 00:44:24,472
concentrated across the world

1267
00:44:24,539 --> 00:44:25,740
is not just the story

1268
00:44:25,807 --> 00:44:30,044
of metal and mining...

1269
00:44:30,112 --> 00:44:31,579
It's an epic tale that has

1270
00:44:31,580 --> 00:44:32,680
revealed how the Earth is

1271
00:44:32,681 --> 00:44:34,481
dynamically changing to this day.

1272
00:44:34,782 --> 00:44:36,382
And over billions of years

1273
00:44:36,383 --> 00:44:37,483
of the planet's history.

1274
00:44:37,484 --> 00:44:39,684
Living proof that the Earth

1275
00:44:39,685 --> 00:44:41,785
is never at rest.

1276
00:44:41,786 --> 00:44:43,786
-- Sync, corrected by elderman --
-- for www.MY-SUBS.com --