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  • Occasionally in books or movies the story will feature a fantastic new and rare element with seemingly impossible

  • Characteristics in the Lord of the Rings mithril is a light but extremely strong metal found only within the mines of moria

  • In James Cameron's Avatar this highly valuable metal was called unobtainium a room-temperature

  • Superconductor found only in small quantities on the distant moon called Pandora most recently in Black Panther

  • This element was the metal vibranium which can absorb any and all vibrations found exclusively in the fictional African country of Wakanda

  • These super materials might seem far-fetched or entirely made up to serve the plot

  • But what if I told you there was an element found on earth that did have special and amazing characteristics

  • Similar to these examples and was really only found in one place

  • This metal is used on anything from aerospace components to lasers from helping treat cancer to fueling nuclear batteries

  • What a foe is also found in fiber optic cables and could also be added to fertilizers to improve plant and livestock

  • productivity on top of that

  • This metal is essential in all modern electronics and without them our phones and computers could not function

  • You might say this is too good to be true, but let me introduce you to rare earth elements

  • Okay, so there are actually 17 elements included under this designation. Not just one but for most purposes they're grouped as a single unit

  • Why you might ask well 15 occupy a single row on the periodic table and the other two scandium in each room aren't far away

  • Their proximity to one another on the periodic table means they all have very similar properties

  • Because of their similar sizes and densities they typically stick together in the Earth's mantle and therefore are deposited in or together typically

  • Where you find one rare earth element, you'll find many others as well and despite their name

  • They're not all that rare

  • We can see on a graph like this where basically the higher the elements are on the graph the more abundant

  • They are in the earth. So up here

  • We have very common elements like oxygen and silicon, but as we go down we'll see most rare earth

  • It's fall somewhere in the middle of the range while precious metals like gold and platinum are all the way down here the most common

  • Of the rare earth elements cerium is about as abundant as copper or nickel on the earth

  • Only one of the 17 rare earth elements is truly rare and that's promethium

  • Every isotope of this element is radioactive meaning it will always decay into other elements over time

  • It's estimated that less than 600 grams of naturally occurring promethium exist on earth

  • But overall except for promethium. They're only moderately uncommon at best

  • The reason they're called rare has more to do with their distribution

  • take a gold despite it being far more rare than these it occurs in the crust is

  • Concentrated veins and this makes the extraction and processing

  • relatively simple and therefore cheap rare earth elements on the other hand almost never occur and

  • Concentrated deposits and instead are much more evenly spread across the planet

  • This makes the mining and refining process far less efficient, and therefore makes their overall extraction more expensive

  • so with few economically

  • Exploitable deposits despite being fairly abundant refined and usable rare earth elements remain well rare

  • Which is a real shame because these things are awfully useful for example scandium can be alloyed with aluminum to drastically increase

  • Tensile strength creating an incredibly strong and light metal used by aerospace companies to decrease chances of failure

  • Nutriyum is used in treatments of certain cancers in a method called selective internal radiation therapy. It's most effective against liver cancer

  • Neodymium is one of the strongest and naturally magnetic materials out there and when alloyed with iron and boron can make those crazy

  • Magnets, you'll see on other science channels promethium

  • the super rare one has been proven to work in nuclear batteries ytterbium is used in stress gauges monitoring for earthquakes and

  • Basically all of these in some form or another are useful in making lasers

  • but when used together their usefulness increases exponentially

  • Several of them are crucial and magnet production which other than being a ton of fun to play with are also crucial

  • Components of engines used more and more on things like electric cars and generators for things like aircraft and wind turbines and even in computer

  • Hard drives many rare earth elements have even been used in agriculture to increase plant growth

  • Productivity and resistance to stress with no observed and negative consequences on the environment or food safety

  • Even adding these elements to livestock feet has caused more growth and even higher egg production from chickens

  • But perhaps most importantly many rare earth elements are essential in electronics, you know

  • The thing you're watching this video on and without them are phones computers and televisions could not function in a rapidly modernizing

  • In advancing world these 17 elements are becoming more and more crucial to our functioning

  • There's only one problem today just one country accounts for over

  • 90% of the global rare earth production

  • China most of this comes from mines in the province of Inner Mongolia the southern provinces and the western province of Sichuan

  • These three areas account for 98 percent

  • of China's total rare earth production and once mined much of these rare earth metals will travel to cities like

  • Shanku where they'll go directly to huge tech companies like Apple and Samsung that have factories putting together

  • Electronics in the city this gives China almost complete control over not only rare earth elements

  • But also the manufacturing of things like smartphones and new computers what has certain countries like the US even more worried

  • however

  • Is the importance of rare earth elements in our defensive weaponry just like consumer electronics the electronics used by the military

  • Things like computers for navigation or steering missiles also rely on these scarce elements without China's cooperation

  • Every military outside of China's could be left in the technological dark at least for a time in 2010

  • They've reduced the rare earth exports by 40% and sent prices outside of their borders soaring

  • Not only did this create an international shortage. It also gave Chinese companies an insurmountable

  • competitive advantage on the global stage in

  • 2014 the United States the European Union and Japan

  • Confronted China's export quotas through the World Trade Organization, and it was ruled in early 2015 that China had to lift its quotas

  • So basically rare earth elements are vibranium and China is Wakanda

  • but like not in a cool way as China continues its attempts to limit its rare earth exports an

  • International search has begun to find new potentially more reliable sources of these essential metals

  • surveys show that China while extremely rich in rare earth elements really only contains about

  • 23% of the total proven world of deposits by many measurements

  • The United States has the second greatest rare earth element potential

  • And in fact before China ruled the market just a single mine in southeastern, California

  • The mountain pass mine supplied the majority of the world's rare earth demand the United States also contains substantial

  • Rare earth deposits in the southeast from Florida to North Carolina as well as in Idaho and Montana

  • It's estimated that opening mines in all of these places could not only eventually surpass China's production

  • But could alone support the growing rare earth demand for the next

  • 280 years another country with large rare earth deposits is Russia with development of the Tom tour rare earth mined reportedly starting in

  • 2013 this single mine has been confirmed to contain

  • 154 million tons of rare earth ore or about 12% of the world's proven or

  • Australia has also been looking into the rare earth potential with the knowlins project and the Mount Weld

  • Deposits receiving a lot of attention recently a Canadian company recently discovered large deposits of rare earth ore in Ontario and Quebec

  • provinces while mining for uranium

  • Specifically the highest lake has given promising results other countries with noted rare earth potential include Malaysia India Afghanistan

  • Egypt South Africa and Brazil, so with so many possible suppliers of these incredibly valuable resources

  • How does China seem to maintain a monopoly on rare earth production?

  • well in short

  • Economics you see while rare earth ore is highly sought after it will usually only contain anywhere from five to twelve percent actual rare earth

  • Elements with the rest being common oxides but really only ores containing eight percent or higher can really be processed

  • Profitably at the moment

  • mining and refining of rare earth elements is highly costly and China seems to be the only country right now with enough of an

  • Economic machine to absorb these costs and still profit

  • this is the result of the cheap labor found in China as well as the government's

  • Prioritizing the development and maintenance of their dominance in the field add on to that

  • The mining of rare earths is highly damaging to the environment not only by scouring the land but also leaking heavy metals into sir

  • Pounding lands and water supplies and any country with moderate

  • environmental protection legislation have real trouble developing rare earth mines

  • so China has the perfect mix of cheap labor and

  • Hands-off environmental policies to allow rare earth mining to thrive the mountain pass mine

  • The one that once has supplied most of the world's rare earth elements closed in

  • 2002 with an estimated 22 million tons of rare earth materials still in the ground

  • It didn't close because they ran out of materials

  • But because they were no longer

  • profiting from their

  • Operations in large part due to competition from China but as China clamps down further on their exports they've begun to tip the scales

  • Against themselves and have made rare earth mining and processing profitable outside of their borders

  • Which is why we see so many countries just beginning to develop their own deposits

  • China has even tried to purchase and control mines outside of their borders and attempts to keep control over the industry

  • But like at the end of black panther this control might change soon if you enjoyed this

  • How about giving a like if you'd like to see more videos like this the subscribe button is there for a reason?

  • Hopefully I'll have another video coming next week. So make sure to check back then if you want some updates

  • You can follow me on Twitter. Other than that. Thanks for watching

Occasionally in books or movies the story will feature a fantastic new and rare element with seemingly impossible

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稀土元素:中国振金(Rare Earth Elements: China's Vibranium?)

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    joey joey 發佈於 2021 年 06 月 05 日
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