Critical Minerals and Rare Earth Elements

Critical minerals are crucial to both the economy and national security. Rachel Teasdale, a professor at California State University, Chico, and program director in the U.S. National Science Foundation Division of Earth Sciences, discusses how critical minerals and rare earth elements form and how we use them.

Episode Transcript

(00:03):
This is the Discovery Files podcastfrom the U.S.
National Science Foundation.
Critical minerals, including rare earthelements, are essential raw
materials and production inputs requiredfor economic and national security.
Rare earth elements are criticalcomponents in almost all modern
technologies, from smartphonesto batteries, hard drives, and satellites.

(00:24):
However, these elementsare notoriously hard to extract
from the Earth's crustand even to separate from one another.
To learn more about critical mineralsand rare
earth elements,we are joined by Rachel Teasdale,
a professor at California StateUniversity, Chico, and a program director
in the Division of Earth Sciencesat the U.S.
National Science Foundation.
Doctor Teasdale,thank you so much for joining me today.
Thank you for having me.
Critical minerals, rare earths,rare earth elements.

(00:46):
We hear all these different terms.Are they the same thing?
Not technically.
So an element and a mineralare two different things in science.
But those terms have cometo have common usage interchangeably.
How does a mineral or an elementget designated as being critical?
So the United States Geological Survey

(01:07):
is tasked with decidingwhat elements are critical
to the national economyand the national defense.
So how do critical minerals form?
Well, like many good things,they are associated with volcanoes.
So volcanoes have magma bodiesat depth in the crust,
and the rocks aroundthose magma bodies are hot.

(01:30):
When fluids percolate through those rocks,
then they're able to pick up or extract
some of the metals that are rare earths
or other important onesthat become critical minerals.
So they get to higher abundances.
They accumulate together.
That doesn't mean necessarilythat they are in high abundance

(01:54):
within a single rock,but they at least are
sort of compiled in similar bodies.
The rare earths occur in low abundances,and that's why they're considered rare.
Our modern societynow really does depend on rare earths.
I mean, we're all using rare earthsright now to record this,

(02:14):
to watch this video.
People are using rareearths in terms of their
maybe they're watching it on a cell phoneor on a computer.
So the battery in the cell phoneor the computer uses neodymium.
The screen that you're watching
any video on contains lanthanum.
The electronics again neodymium.

(02:36):
Some cobalt.
So we use it every dayin cell phones or computers in our cars.
There are lots of rareearths and critical minerals.
So petroleum products are processed
using rare earths and critical minerals.
Power steering uses them as well.
So pretty much every aspect of our modernlives is reliant on them.

(03:00):
Are there only certain specificparts of the world where you can find
rare earths and critical minerals?
There are different geologic regions
that will host critical mineralsor rare earth elements.
They happen to be locatedall over the world,
but they are in specificgeologic environments.
Can you elaborate a little biton the environments?

(03:21):
Like like I think I was thinking like,did they follow the Ring of Fire or
something like that?
Where or where the edges of plates are?
What about these forms?
Make them occur in specific places like.
Rare earth elements or critical mineralsoften are associated with volcanoes
and so where we have volcanoes,there's a good chance that they will also
host rare earth elements or minerals.

(03:43):
They also do occur in placeswhere there are,
we call them evaporate environments.
So a shallow sea or lake.
And in that case,the rare earth elements will be associated
with mineralsthat form by evaporation processes.
So as water evaporatesfrom a shallow water environment,

(04:04):
minerals will crystal riseout of those environments.
And sometimes rareearths are associated with them.
Another place where we find rareearths is where the rocks that formed from
the magmas have eroded,so we might find them in stream beds,
or at least in mineralsthat are found in stream beds.

(04:24):
And scientists are looking for those.
We support scientistswho look for these deposits of rare
earths,both with the idea of looking for places
that might be mineable,but also places where the rare earths
might have accumulatedfrom other processes.
In fact, the U.S.

(04:44):
National Science Foundation is criticalto the critical mineral industry.
We have scientists we are supporting
who are involved in thethe geologic processes
where are critical minerals located.
How can we refine those critical minerals
so that they occur in concentrationsthat are useful?

(05:07):
We have chemistswho are working in similar processes.
We have materials scientistswho we support in all aspects
of critical minerals,particularly in the production
of materials, in ways that they might bemore recyclable at the end of their life.
We have engineers that we supportwho are also working on critical minerals

(05:30):
in terms of designing electronicsthat maybe use different rare
earth elementsor different critical minerals,
and looking for substitutesso that we have a diversity of minerals
and elementsthat we can use for electronics.
National defense,and those kinds of important areas

(05:52):
to our national well-being.
Can the United States or do we produceour own critical minerals and rare earths?
We have one mine where we doextract rare earth elements,
and there are a couple othersthat are under investigation.
So scientists are looking to seeif the rare earths occur in a large enough

(06:14):
abundance that they might be efficientenough to be mined.
But we don't produce very muchin terms of processing and refining.
I mentioned that these rare earthsoccur in low abundances,
so that means it's a more challengingand expensive process
to extract the actual elementsfrom the rock body that they're found in.

(06:35):
And most of that is occurring in China.
And so we're importinga lot of what we use.
But there are scientistswho are partnering with industry
to try and developand get into production.
These processing facilitieshere in the U.S.
so that we can reducethe risk of supply chain issues.
Can you talk a little bit abouthow might you refine rare

(06:57):
earth elements to get to the bitsthat you need from other forms.
At a bulk level you can imagine a rockthat has a whole bunch of minerals,
and very few of them contain rare earths.
And so first we have to crush that rockand get it into smaller pieces,
and then they go througha series of chemical processes.
And so chemists are working on developingprocesses that make that more efficient.

(07:23):
When the rocks are being broken downthere's a lot of waste.
And that waste can get stored at the minein these big tailings piles.
And one of the really cool thingsthat our scientists are finding out now
is that we can lookin those giant tailings
piles and find materialsthat now have critical importance.

(07:43):
They may not have had that importanceat the time that they were mined,
but now they do.
And with scienceand research our geoscientists
and chemists and engineers are developingways that we can more efficiently
extract those rare earths fromwhat was once considered to be waste.
I'm aware of one case where with thealuminum process, they have this red mud.

(08:05):
That's exactly what you're talking about,where it's the byproduct of the process
that can, in fact, produceother things of use.
Yeah, that's exactly it.
The aluminum processing createsthese ponds
where the aluminum is in high proportion.
It happens at other mines as well.
And other materials, othercritical minerals or rare earth elements

(08:27):
accumulate in similar ways.
And like I said before,it was considered to be waste material
and would just be stored for the ages.
But now we're developing ways
that we can extract thatso that we're basically mining the waste.
Thinking about this from a little bitof a different perspective,
for these rare earths that have been usedin, say, computer chips or something,

(08:49):
can we recover those elements and recycleit to be used again?
Or is the lifespankind of not useful in that way?
We absolutely can recover rare earthsfrom existing materials.
A lot of timeswhen somebody gets a new cell phone,
they throw the old one in a drawer andit's sort of a hidden stockpile, right?
Because that cell phone has all the rareearth elements

(09:12):
that we were talking about before.
And so we basically have these sort ofmini mines in all of our kitchen drawers.
If those cell phones were recycled,then we could extract the elements
that we need for national defenseand for our national economy.
So we want to make sure that oldcell phones and electronics

(09:33):
and all the other materialswhere we are using rare earths,
we want to make surethat those are being recycled as well.
And another really excitingarea of science is where engineers
and material scientistsare trying to figure out ways
to build those products
in the first place,where recyclability is more likely.

(09:56):
So if it's really hard to get somethinglike neodymium out of a material
that was used to create it,then it's going to be harder to recycle.
But new science is being workedon where they can make
the neodymium a little more extractableout of that battery.
So what are some of the ways you see
NSF supporting these national prioritiesaround critical minerals?

(10:19):
NSF supports the science behind
critical mineralsand rare earth elements every day.
And we have scientists who are looking for
new sources of critical mineralsand rare earth elements.
We have scientistswho are looking for ways
we can extract those elementsin more efficient ways,
in waysthat have less impact on the environment

(10:43):
or on the communitieswhere these mines exist.
We have scientistswho are working on more efficient ways
of processing the elements
so that we can get more of themfrom every
bit of rock that is produced.
We have scientistswho are working on ways to recycle.

(11:06):
The other way that NSF is supportingcritical minerals and and mirrors
element technologyis by helping to create the workforce
that's needed to train more scientiststo work in
all these aspectsof the critical mineral industry.
So thinking about that workforce,where do you see

(11:27):
that fielddeveloping in the next few years?
Well, right nowthere's a shortage of workforce.
So jobs are very much available
for folkswho have an interest or some training
in areas of critical mineralsor the critical mineral industry.
So, I mentioned geoscientistswho are looking for

(11:49):
these geologic depositsthat contain the critical minerals.
Hydro geologistslook for water or clean sources of water
or ways to remediate waterthat's been contaminated.
And water is a huge partof the critical mineral processing.
And so that's a growing industry.
Chemists and materials scientistsand engineers are all involved as well.

(12:13):
And then, of course, in the workforcedevelopment itself, we need educators
and partnershipsbetween industry and scientists.
So all of those areasare really a growing industry
and a really valuable industry to the U.S.
success economicallyas well as in national defense.
So I think for my last question,I want to ask you

(12:35):
about whatwe'll see in the next few years.
You mentioned scientists are out therelooking for other caches
of these rare earth elements, basedon your understanding of volcanology.
Would you expect there to be a lot morethat we haven't found yet?
I think there's definitelya lot more sources out there.
There are lots of geologic regionsthat haven't been explored

(12:55):
or are currently being exploredby scientists who are supported by NSF.
Other ways that I thinkthis industry will move forward
is some of the thingsthat we already talked about.
I think the development of materialsin ways that make them more
recyclablewill be an important part of our future,

(13:16):
as well as making more efficientthe recycling process itself.
Chemists and materialsscientists are working on ways
to process the critical minerals, as well
as in the construction of productsthat use them.
So I think those are all the way forward.
And again, a really excitingpart of the geoscientists

(13:39):
role is in finding ways
to process waste material.
We already have it at the surface.
We don't need to diganother big hole to access it.
And what was once considered
waste can be critical to our economyand our national defense.
Special thanks to Rachel Teasdale.
For the Discovery Files, I'm Nate Pottker.

(14:00):
You can watch video versions
of these conversations on our YouTubechannel by searching @NSFscience.
Please subscribe wherever you get podcastsand if you like our program,
share it with a friendand consider leaving a review.
Discover how the US..
National Science Foundationis advancing research at NSF.gov.