PlanetGeo: The Geology Podcast
PlanetGeo: The Geology Podcast
The Devil's Metal - The Geology of Nickel
Use Left/Right to seek, Home/End to jump to start or end. Hold shift to jump forward or backward.
Today, Jesse and Chris discuss the geology of Nickel - The Devil’s Metal. Surprisingly, Earth’s core has a high percentage of Nickel - 10 to 20% of the core is nickel. We allow ourselves the luxury of getting into the details on nickel and why the core has so much. Of all the metals we’ve discussed on the podcast, the geology of nickel is the most complicated. In addition to discussing the geologic settings that form or concentrate nickel, we also spend some time discussing the history and uses. We hope you enjoy the discussion.
Download the CampGeo app now at this link.
On the app you can get tons of free content, exclusive images, and access to our Geology of National Parks series.
You can also learn the basics of geology at the college level in our FREE CampGeo content series - get learning now!
Like, Subscribe, and leave us a Rating!
——————————————————
Instagram: @planetgeocast
Twitter: @planetgeocast
Facebook: @planetgeocast
Support us: https://planetgeocast.com/support-us
Email: planetgeocast@gmail.com
Website: https://planetgeocast.com/
Welcome to Planet Geo, the podcast where we talk about our amazing planet, how it works, and why it matters to you.
SPEAKER_00What happened? I can hear you now. Oh, you can hear me now. Oh, okay. Can you hear me? Yeah, yeah. Yeah. I can hear you. Mr. Boy. Bohuis. Bohuis? What's up, man?
SPEAKER_02Jesse Rhymink. What's going on, man? It's been a long time since we've it feels like a long time. It probably hasn't been a long time, but it's true. We haven't talked very much lately. I know. I know.
SPEAKER_00It's good to see your face, I must say.
SPEAKER_02I bet. It's always good to see my face. In fact, Jesse, hey, the last time we were talking.
SPEAKER_01That was a very good reaction. You know what? If anybody was in doubt about Chris Bullheis's opinion of himself, that answered it right there. Just, hey Chris, good to see you, man. Yeah, you know what? It is usually good to see me, isn't it?
SPEAKER_02Well, the last time we talked, Jesse, you called me. I was driving in the like sticks of Red River Gorge, Kentucky. Yeah, I know. You dropped my call and it's a little bit more. I don't know, but I gave you fair warning. I said, hey, listen, we can keep talking, but I'm probably gonna lose you here in a few minutes, and all of a sudden, bam, you were gone.
SPEAKER_01It was out. Yep. I was like, okay, well, there we go. It wasn't important anyways we were talking about.
SPEAKER_02How long were you talking before you figured out that I had dropped?
SPEAKER_01Oh, at least a minute or two, you know, probably. Yeah, Jenny and I laughed about that. Yeah, we're like, he's probably still talking right now. Well, there are some times when the you know the hamster, it's not clear if the hamster's on the wheel or not over there with you, and you know, you get slack jawed looking at me through Zoom, and and then I have to say, Chris, are you frozen? You're like, oh no, I was just listening, or I was just thinking.
SPEAKER_02Yeah, I was daydreaming because you get windy. And uh it I just he's not uh he fell off the wheel.
SPEAKER_01Yeah, that's true.
SPEAKER_02He the wheel broke quite a lot.
SPEAKER_01The wheel broke because he was moving too quickly. And Chris, this episode right here, I think we could get super in the weeds on this one. Definitely we're gonna go into the weeds. Like this type of topic. We've been doing these the geology of fill-in-the-blank element, and I really like doing these ones. I know you you do too. And they're really interesting and important in like some of the more societally relevant, just because like sand, we did the geology of sand, we did the geology of copper. I mean, it's just amazing how important these these resources are to our society at the end of the day.
SPEAKER_02That's right. So you put the script together, and one thing that struck me is this is I think easily the most how do I say this? It's easily the most complicated in terms of the geology of nickel and and the kind of the backstory on it. So I'm curious about that, because we've done a bunch of this stuff, Jesse. We've done lithium and we've done the platinum metals, and and then all of a sudden we get to nickel, and it's whoa, this is at a different level. So what is this?
SPEAKER_01I think Chris, the okay, this is just my take. It has to do with the nickel is a I wouldn't say unique, but it's definitely different from things like lithium. Lithium, for instance, we talked about lithium, how basically in the really high level, the the intro-level physical geology understanding of the earth, the earth is differentiating itself, it's partially it's distilling, right? And lithium just gets enriched at each differentiation step. So it's kind of at a really high level simple. Nickel's not that. There's a couple different ways to make nickel-rich deposits, and they're very, very different from one another. And so I think that's perhaps why we it's gonna be a little bit of a confusing web to kind of get into the meat of this story, perhaps.
SPEAKER_02Is that I don't know if I agree with I I appreciate your answer to this. It's just it's more complicated. The basic geology behind nickel and how this gets concentrated into like an ore deposit is more complicated. But I think you did a good job. I mean, it flows. I I don't think we're gonna have a problem with that. We're gonna go through the early uh how do we say this? We're gonna go through the beginnings of the mining of nickel because I think there's some interesting stuff in that, you know. Then we're gonna get into some of its uses. Why has nickel been important and why is nickel gonna become increasingly more important as time goes on? We're gonna talk about that. Then we're gonna end with all right, let's get into the geology of concentrating nickel. How does this happen? How does it form? And uh so it flows, it's it's good. That's basically the gist of this episode.
SPEAKER_01And I think there's a there's a really high-level summary here that most of the nickel on earth is in the core. We speak about the core being an iron-nickel alloy, right? And so the core is huge. There's two parts to the core, inner core, outer core, but it's mostly iron and some nickel. And then there's a little bit of some other light element that geologists argue about, but iron-nickel alloy. So most of the nickel is gonna be in the the core. The rest of it is gonna get enriched in various parts of the earth and then eventually form some ore deposits. And we're gonna end with with coming back. But Chris, when we talked about copper, copper has the nickname the red metal. And I think Jenny was giving you a hard time about this, right? Jenny was like, Chris, it's not even red, it's a copper color. Is that wasn't that what she was saying about it?
SPEAKER_02Yeah, it was. It was.
SPEAKER_01Jenny gets a little uptight about some things. So I'll be excited to hear what Jenny thinks about the nickname for nickel, which is the devil's metal. That's a good one. Isn't it? It's just catchy. It's just it's catchy right there. It might be the best one. It might be the best nickname for a metal that I've heard.
SPEAKER_02I want to back out of this a second, though, Jesse, because I want to talk a little bit about something that you said first. You said that most of the nickel is in the core. Two things I want to say about that. We think that about 10 to 20 percent of the composition of the core is actually nickel, which is an astonishingly high amount, right? Now, I think this right away begs the question from anybody that is skeptical about really anything is wait a second, how in the world would we possibly know that and arrive at that number? We've never seen the core, we never will see the core. So let's address that, I think, first. How would we ever come to that realization that there's that much nickel in the core, something we've never seen and never been able to sample?
SPEAKER_01It's a great question. And I would say there's there's two ways. We've talked about, and we talked about this in the camp geo content. We're talking about plate tectonics and the the initial content to get into that is we have to think about the interior of the earth. How do we know anything about the interior of the earth? There's two ways. One is with physical measurements, and these are seismic, usually how seismic waves travel through the earth, how fast they travel, what they reflect off of. We can intuit some things about the composition of the inner parts of the earth from that. The second one, and probably the more important, is analogs. Analog studies. And what we mean by analog studies is we look at meteorites that come from small planets or even the precursors to planets, iron meteorites, for instance. And we can look at iron meteorites and say these meteorites, this iron, well, iron and nickel stuff that's in an iron meteorite, that was probably the core of some small planetesimal. We can determine that it definitely was the core, and then we can look at that and say that's an analog for Earth's core.
SPEAKER_02So you're looking at then the formation of our solar system, basically, or the formation of any solar system for that matter, this kind of solar nebula theory, right? And in terms of how these smaller bodies started rotating all in the same direction and kind of were rubbing shoulders and accreting into larger bodies that were destined then to become planets and sweep out their own orbit. So looking at the composition of these things that we've been able to study and we know their internal chemistry and so on, that leads us then to kind of what the interior of the earth has to be like, right? The only other thing that I'd add, Jesse, is also what does nickel do? And we're going to get into this later on in the episode, and we've alluded to it in another episode that nickel is acidrophile. Nickel is an iron-loving element in terms of early formed crystals that form in this kind of magma and then sink down toward the middle, right? And so, based upon what we know about the way nickel behaves, we can make an inference on that also. So it's it's really a bunch of different lines of evidence that point to this.
SPEAKER_01That's a great way to phrase it, Chris. And I like the way to think about this is that as the core is forming, it's kind of like a sponge. It's iron, mostly iron, and so it soaks up, it's spongy, and it soaks up all of the iron-loving elements on the way down. We talked about iridium being one of those. This goes back a year and a half, or maybe even two years now. We talked about the geology of iridium. Iridium gets soaked up. Gold is another one. Gold will get soaked up. There's a bunch of gold in the core, way more gold in the core than there is on the surface of the earth. And nickel is another one of those. And so, you know, those elements, when earth formed, they got soaked up into the core. Not completely, though. Not completely. That's the important point.
SPEAKER_02All right, so let's save that for later. I just wanted to back out and address that issue. So let's move into then this kind of early part of the devil's metal.
SPEAKER_01Yeah, now, Chris, really quick, just before we jump into that, I just want to there's a through line here that nickel and iron kind of go together. They usually go together, but not always. And that's kind of, I think we're gonna work through this discussion saying they behave together in this intro part too. And then there are some places where they behave differently, but remember that iron and nickel often behave together. So interrupted, go ahead. Where does this amazing nickname come from? The devil's metal.
SPEAKER_02Well, it really actually goes back to Germany, right? With the early miners and and they were trying to extract copper from this dark red mineral, okay? And that dark mineral had green coatings on it, and so they they thought it was some form of copper ore, but it turned out to not be the case.
SPEAKER_01Well, Chris, it makes sense, right? Like we've talked about copper. One of your favorite minerals is malachite, that bright green copper mineral. And I don't know, when I'm walking around in the field and I see that that particular kind of it's not quite pistachio green, it's it's almost a more vibrant, darker, deeper forest green. You think immediately copper, right? And you think this all the time because copper, when it's oxidized, it turns into this kind of greenish mineral, this greenish coating, right? And so I don't know, I think back in the day in sort of old Saxony, uh, they would have thought, oh, green, okay, there must be copper somewhere around there, let's dig around for it. So that's the signal.
SPEAKER_02Well, they didn't really know what the mineral was, and so they this is also fun to say, right? They called the mineral cup for nickel.
SPEAKER_00Yes, I love it.
SPEAKER_02Which it comes from it's called Old Nick's copper. Okay, old Nick's copper. And they they called it this because, like you said, you just alluded to it, Saxon mythology, old Nick he was an evil spirit in this Saxon mythology. And so they now okay, so Jesse, why did why did they think of this as an evil, like why did they associate it with evil?
SPEAKER_01Well, you're trying to get copper out, which you really want to make your your tools out of, and it turns out that all of the miners and workers who are trying to get the copper out got really sick or even died because they're dealing with what this mineral actually is, is it doesn't have much copper in it at all. It's a nickel arsenic mineral called nickelite, N-I-C-C-O-L-I-T-E, nickelite. And the combination of nickel and arsenic is a really poisonous mixture. So they're poisonous on their own, separately, right? Like any arsenic-bearing mineral is going to be really quite dangerous to handle, let alone handle in ancient times.
SPEAKER_02Um, so this is where the But you're talking about handling a large quantity of it.
SPEAKER_01Yeah, crushing it up, mining it, really, you know, in the old and news sort of exposed to it again and again and again. Oh my goodness, yeah. So this is where they got the term the devil's metal or old Nick's copper, that Kupfer nickel that you said. So that's the uh it's just a great story. I mean, it's not a great story, it's sad story, but it's an amazing nickname for a metal, and that's the the sort of source of it.
SPEAKER_02So, Jesse, let's move into then why is nickel aciderophile? And it can also be, like you said too, a calcophile, which means that it's a sulfur-loving mineral, too, to form these kind of nickel sulfides that you just alluded to. Um let's get into a little bit of the chemistry on this, right?
SPEAKER_01So we'll transition from uh the chemistry and the usage. Those kind of go hand in hand here. So nickel, Ni is the the element, and it has a two plus charge. Its oxidation state is usually two plus, which means it's happiest when it has two electrons removed from the outer orbital, so it maintains a cation status, Chris. And what is a cation? How do we remember a cation?
SPEAKER_02Well, actually, actually, I want you to say it because I want to see I want to see if you get it correct. Okay.
SPEAKER_01It's positive.
SPEAKER_02You did not disappoint.
SPEAKER_01It's positive. Positive. Pa. It's positive. Pa. Say paw. Like a positive. It's a c ion, like a cat has paws. It's positive. Um nickel 2 plus, it the reason it's sitter phile, the reason it is calcophile is it's got this 2 plus charge state, has an ionics radius much like iron 2 plus and magnesium 2 plus. So it's gonna go, we're gonna remember this. It's gonna go along with iron 2 plus and magnesium 2 plus in most geological systems.
SPEAKER_02Can I give this a crack? You're getting doctory on us again. So the way I think about this is in terms of why does it love iron-bearing minerals and sulfur-bearing minerals is because nickel is a good substitute for iron. It's the same size, it fits in the crystal structure of these other minerals. So, what I'm what we're saying, right, Jesse, is that if if there's iron and nickel around, they just use it interchangeably. Iron can go in and nickel can go in, and it really doesn't differentiate between the two.
SPEAKER_01So that's a really good way to phrase it because we it allows us to think about major elements and minor elements, and nickel is not a major element. So we're not going to build minerals out of nickel. The internal structure or the framework of the mineral, we're not going to build it with nickel. We're going to build it with things like iron and silica, because those are that's that's a major part of the recipe for the rock. And so nickel is substituting in for iron in that lattice, in that crystal lattice. And that's the difference between iron, which is a major element, and nickel, which is a minor or trace element, is that we don't build nickel minerals very frequently. We build iron minerals, and then nickel substitutes in for that, like olivine, for instance. So I really like that way you phrased that there. That was really nice. That is substitution is the key.
SPEAKER_02Jesse, a thought just popped into my head that I want to run by you here, then when we're talking about this. Because if nickel was the wrong fit, if you're building a wall and you want to put a block in the wall that has to fit, right? You can't be the wrong size, it can't be the wrong shape, it has to fit. If nickel were the wrong size, then nickel would concentrate in very different ways, then, right? If it didn't fit in the crystal structure, nickel would have a completely different geological story because nickel would just kind of have to hang around. If you imagine nickel in this kind of magma, this primordial soup, it has no place to go because the common minerals are forming, these iron and magnesium-loving minerals, nickel doesn't fit in the crystal structure, so it just kind of has to hang out. And then it would have a different geological story.
SPEAKER_01Exactly. So the way to visualize this, Chris, that's a I I love that one. It actually makes me think how to explain this better in when we teach this sort of basic stuff. Think of if you have just a big old pile of building material supplies. You got cinder blocks, you got bricks, you got bricks of different colors, you've got some wood beams, you know, you got screws and all the stuff you need to build a house that's laying in a big pile, and you need to build a wall. Well, what are you gonna start building the wall out of? You're gonna look and you're gonna be like, well, I've got a ton of bricks, I only have a couple cinder blocks, so I'm gonna build the wall out of brick because I have a bunch of that, right? So you're gonna build a brick wall. Now, those cinder blocks are not gonna fit in to your brick wall very easily, so you're not gonna use them, they're just gonna hang out. That's like lithium or neodymium. We've talked about those elements. They don't fit in. Now, nickel is like a just slightly different colored brick. If the brick is iron, so you've got your red brick, that's your iron, and you've got maybe some brown brick, and that's your nickel. And that can just replace, that can go into your brick wall, so you don't really care because it fits. And so that's the really important part here. And so nickel behaves what's called compatibly, meaning it'll go into minerals, especially the early forming minerals like olivine, pyroxenes, and we'll come back to this later after we sort of talk about the uses of nickel. Yes.
SPEAKER_02All right, Jesse, then some of the properties, right? So we established that it loves iron because it fits in iron-bearing minerals. It also fits in sulfide minerals, it fits in there very well, but it's also useful because it has a really high melting point, upwards of close to 1500 degrees Celsius. It's also really corrosion resistant, at least as a pure mineral, right? If you have pure nickel.
SPEAKER_01Yes. And so that is really useful. Let's just calibrate that 1500 degrees centigrade or 1450 degrees centigrade. You know, basalt melts at 1200 degrees, the rock basalt. Olivine starts to crystallize at 1400 degrees. So this is this is hot. This is really hot. And this corrosion resistance, well, I think it kind of it's easy to imagine how we would use nickel in society is that most of it goes into stainless steel. So you put some nickel in with your iron and your little bit of carbon to make steel, and you have stainless steel, which is much more corrosion resistant, right? That that's the main use. About 65% of the nickel used is used for stainless steel.
SPEAKER_02I think one thing I want to do to qualify that number, Jesse, you said 65%. I think that the relative percentage of the use of nickel for stainless steel is going to go down as time goes on, because it's also important in making this transition to net zero carbon. And we'll talk about that a little bit, right? So that that's like as of now, that's where the number stands.
SPEAKER_01That's a great point. And we've talked about critical minerals and critical elements before. Nickel is added to the critical elements list because of this aspect, because of the future uses, potential future uses of nickel, or you know, uses today, but these are going to be growing over time. So, all right, Chris, what else do we as a society use nickel for? Why are we so interested in mining it?
SPEAKER_02Another use for nickel is to combine it with other metals, right? We call these alloys, but with nickel, it's actually called a superalloy. So, which I think makes sense. We don't need to explain that. Which it it means it's got about 50 to 70 percent nickel in it, though. And these things are stable because they have the properties of nickel, right? They're stable at really high temperatures, which makes them really useful for things like turbine blades. Think of the turbines at an electric power station, right? So they'll use these nickel super alloys as a major component of these turbine blades and discs and other critical components to like jet engines, right?
SPEAKER_01So things that need to kind of important kind of important things that we don't want to, we need to be able to produce and we don't want to be breaking down, right? And the point here is that you add some nickel, well, you take a bunch of nickel, you add some other elements to it, and you get an alloy that's super strong, super stiff, to really hot temperature. Exactly. Just said a lot of turbines. I I don't know, because that was a really interesting one to me. Think about next time on an airplane, that nickel, what we're where we're getting all this nickel is in the in these turbine blades, which obviously you need that to be real. That's a critical piece of infrastructure right there, let alone the power generation.
SPEAKER_02That's right. But now, Jesse, we're beginning to use it increasingly for other things. Um, we do make other alloys, so the last like 23% of the nickel that we have, we use it for other alloys, but we're using it more and more in batteries now, which I find to be really interesting in terms of like electric vehicles, but also, you know, I've talked about this. I I love, love, love my power tools that I'm converting all of them to battery. And nickel is a really important component in these lithium-ion batteries.
SPEAKER_01Yes, absolutely. It works as a cathode in these, and so just adding nickel, I mean, it's it's a it's an essential constituent part to the lithium-ion battery. So there's been a lot of focus on nickel because of this. It's critical, it's a critical element, critical mineral because of this aspect, the battery part.
SPEAKER_02But Jesse, you spent a lot of time in Canada, and they still use nickel as a part of their currency, right? Do you have some of this still left around? I do.
SPEAKER_01Yeah, you know, I've got my random like drawer or like Ziploc bag with like random currency from you know, travels, you you pick up, you know, pounds in London or whatever, and you end up with a couple left over, chuck it in the bag. So yeah, actually, I looked and I do have some a bunch of Canadian coins. Um and they do. So like the 10 cent, 25 cent, right?
SPEAKER_0250 cent, and the I think they have a dollar coin, right?
SPEAKER_01Two it is it all is all of that stuff pure nickel? Chris, Chris, it's not called a dollar coin, it's called a loony because it has a loon on the back. And then there's a two-dollar coin which is called a toonie because it's worth two loons.
unknownYeah.
SPEAKER_02Okay. Interesting fact. You know what? I love loons. That is I appreciate that so much.
SPEAKER_01Actually, loons are probably one of my favorite. I mean, certainly my favorite waterfowl. They're just amazing. I mean, there's nothing better than hearing a loon on the lake where you're sitting there on the dock, you know, in the evening having a beer or whatever.
SPEAKER_02For the listener, though, because I you threw me for a loop right there, it's waterfowl, not waterfall. Um Waterfowl, sorry. I I we don't want Joyce to get confused that a loon is a waterfall.
SPEAKER_01It's the geologic term for a waterfall uh with a sandstone cap.
SPEAKER_02Yeah, so anyway, are they pure, though? You didn't answer the question. Are they pure nickel?
SPEAKER_01Yes, m many of them are. Okay. And uh and you know, we're that seems Exceedingly wasteful to me. Well, this might be changing, Chris. I mean, you could expect this to change because the total demand for nickel is expected to double by 2040 because of this battery demand. So you could imagine you wouldn't want to be making your coins out of a critical element because the supply chain is really sensitive. Like there's all these factors that we've talked about before on this podcast about the critical supply chains here. You don't want to be making your currency out of stuff that's getting more valuable and more expensive over time, right? Right. That'd be bad idea.
SPEAKER_02Then the dime or the 10 cent piece or the loony will actually cost more to make than it's worth, and that doesn't make sense. Exactly. But Jesse, here it is, right? I would be wondering, okay, well, what is it about nickel then, right? Why is it so important to use in these lithium-ion batteries? And the bottom line is that it has a really high energy density, which basically means that it has a much higher storage capacity. So if you think about an electric vehicle, then if it they employ the use of nickel in this, then you can go much further on a single charge using nickel than some other substitute.
SPEAKER_01Let's introduce here, Chris, one difference between iron at the moment. Because nickel and iron, we said before, they're very similar and they can substitute for each other very frequently. Iron, however, has this multiple oxidation state. It can be a two plus, it can be a three plus, and it can change, and iron will oxidize. And so, you know, we have hematite, we have magnetite. Those are different oxidation states of iron. Basically the same formula, just different oxidation state. Nickel is usually in most geologic settings only a two plus. So that makes it really stable for the battery. You don't want this element changing oxidation states in your battery. And so using one that just sticks with pure two plus is really useful for making the batteries out of it. But it also is really important geologically and helps us think about how nickel and iron behave differently in certain settings. So let's talk about that aspect, Chris. Like let's move into the geologic settings. Where do we get the nickel from? And there's going to be one where it behaves very similar to iron, and then there's going to be one where it behaves differently from iron. And there are two, uh, Chris, just like the high-level thing, these could not be more different settings on Earth, really, I don't, at least to my mind.
SPEAKER_02Well, I think as a way of introducing the geology of concentrated nickel, let's talk about fractional crystallization, Jesse, which is something that we I think are both pretty comfortable with. We've done a lot with this and we'll talk about Bowen's reaction series and so on. And this really fits nicely into like a Bowens discussion, right? Is the concentrating of nickel. Because, well, fractional crystallization is basically the high temperature minerals, minerals like calcium-rich plagioclase, olivine, pyrixene, and so on. These high temperature minerals they form first and they're in this primordial soup because they form first and as they grow, they sink to the bottom. Right. And so when this happens, they essentially get removed from the soup, from this magma, this residual magma, right? Which changes the composition of the magma. Nickel does the same thing. Because if iron is these olivine and pyrixene, these are iron-rich minerals, right? If there's nickel around, nickel is going into that crystal structure too, and it's sinking to the bottom. So this fractional crystallization is concentrating nickel in this way. And as time goes on, it's also depleting the magma from the nickel that's left.
SPEAKER_01That's a great way to phrase it, Chris. And I think we can just think about your average basalt. Look at your minerals in your basalt. Let's say we have plagioclase, olivine, clinopyroxine. Maybe there's a little bit of biotite in there or something, maybe a tiny bit of quartz. But where are you gonna look for your nickel? You're gonna look in the olivine. The first crystallizing mineral, nickel loves going along with iron. Iron is very enriched in olivine, and so that's where your nickel is gonna be. Your olivine has most of your nickel in it. And so nickel's removed from the magma. So you wouldn't look in a granite for nickel, you'd look in a basalt or even better yet, an ultramafic rock, a peridotite, something that's really, really mafic or ultramafic. That's where we look for nickel in a magmatic sense. So let me say the two sources of nickel, deposit types for nickel, Chris, and then we'll focus on number one and then number two. The first one is what we call magmatic nickel sulfide deposits. Those words, magmatic, okay, it's an igneous rock, nickel sulfide deposits. So the rock itself is magmatic, but it's high in nickel and sulfur. That's one thing. We're mining igneous rocks, usually ultramafic rocks. The next one is what's called laterite deposits. And these are or laterite deposits. These are weathering deposits. We'll come back to those where nickel is enriched by the weathering process. But I think, Chris, the first one, this magmatic nickel sulfide, this is a really interesting one because we just talked a couple weeks ago, a month ago, about uh Bone's reaction series and how, you know, it's a great teaching tool, but maybe not, you know, as widely applicable as we sort of say it is in the intro classes, right? And I think this is a really good representation of that. This magmatic nickel sulfide deposit, what this is thought to be is if you take an ultramafic rock or an ultramafic magma, excuse me, and you take that thing at high temperature, it's got a bunch of nickel, it's got some sulfur in it, it's got a whole bunch of iron and magnesium, a little bit of silica. If you cool that down, you can get nickel sulfur liquids, well, really iron nickel sulfur liquids that segregate out from the silicate liquids. Think like oil and water. They kind of separate at lower temperature. And these are really, really cool rocks because if you take an iron, nickel, sulfur liquid and you crystallize that, you're gonna get crazy minerals that are rich in nickel and iron and sulfur. These are pyritites, calcasites, petlandites. The really unique rocks they don't have.
SPEAKER_02Minerals that most people have not heard of. No, have not heard of, have not seen.
SPEAKER_01Unless you're like an economic geologist looking for these things, or you know, some great museums have ore deposits. If you go to an ore, like a School of Mines museum or the Black Hills, you know, if you go to the South Dakota School of Mines museum, you'll see these types of minerals around, but they almost always only occur in ore deposits. That oil and water segregation, two different liquids. You have a silicate one that's gonna form all the olivine and the and the pyroxines and the quartz, and then you have a sulfur iron one, which is gonna form all these kind of crazy ore minerals in it, and they separate out from one another.
SPEAKER_02All right. Well, Jesse, I want to talk about one of the areas that can do this or where we can see this maybe, and I want to talk about this one because it's kind of it's close to home for me. If we talk about a magma chamber that fed something like a flood basalt, okay, think of the Columbia River flood basalt, if you will, out in Washington and Idaho and so on. Or in Michigan, we have this Keweenaw Rift Basin. So this is up in Michigan's copper country, and this was essentially a cool geology.
SPEAKER_01I mean, northern Michigan, as boring as the lower, in my opinion, as generally boring as the lower peninsula of Michigan's geology is, the upper peninsula makes up for it because it's got crazy stuff like this.
SPEAKER_02That's true. It hurt me a little bit to hear you say the boring geology of lower Michigan, but you're right. We don't have a lot of bad rock, and and therefore to guys like us, that can be a little bit boring. But basically, in the Precambrian two billion-ish years ago, the continent began to rift apart. A narrow arm of the ocean invaded the area, and up in the upper peninsula, then we get the features that you would expect to see with this, right? When you have lava erupting out onto the ocean floor, you get pillow basalts, and there's just world-class pillows. I took you up there when you were a high school student once. Uh we went behind menards. Yes. Um, and they had these famous menards outcrops. They're gone now, right? Did I tell you that? They're gone.
SPEAKER_01Yeah, they're gone. You said that.
SPEAKER_02Yeah, yeah, yeah. They got dynamited, yeah, that's right. Yeah. So anyway, that rift eventually failed, but this is the kind of thing, this mafic and ultra mafic material from deeper down into the mantle. It fed it out onto the surface. And this is one of the settings where we're gonna get potentially anyway, a nickel ore deposit.
SPEAKER_01That's right. And this is the Duluth complex. These are gonna be the sort of feeder plumbing system, magma chambers beneath the sort of rift basalt. So they're you know, they're related to these rift basalts, but the segregation you can kind of imagine we need time, we need to be in a magmatic setting. This doesn't happen that much in lava flows. So it's the roots to the the basalt flows that's generating these deposit types that then the roots get uplifted and eroded and exposed and tilted.
SPEAKER_02So because it came from deeper, right? And when it comes from deeper, it's gonna be ultramafic as opposed to mafic. It's gonna be richer in these minerals like olivine and pyroxene and so on that are gonna be more likely to have nickel in the chemical composition.
SPEAKER_01So, Chris, have you ever taken, you know, on that field trip, have you ever taken them over to the Duluth complex in Minnesota or you're into Iron Country, you know, kind of further west across the border there, or or not? It's kind of a trek.
SPEAKER_02Yeah, it is. I have not taken my geology students across state lines, but I've taken them up the Keweenaw Peninsula, though, all the way up to Copper Harbor.
SPEAKER_01Oh, right. Okay. So you went up the arm of the basalt flows there. Yeah, gotcha. It's a bit of a trek to get from there, even though they are related. It kind of it's long. It is so far away. It's a ways away. It's a ways away. Up in that region is another really famous and high grade deposit type or tectonic setting that form these nickel sulfide deposits is the Sudbury Igneous complex. And this is a really cool one, kind of near and dear to my heart, Chris. It's a 1.8 billion-year-old meteorite impact crater, and this is a very large impact crater, one of the big ones that we have preserved on Earth. And uh, it's the second largest impact crater that we have preserved on Earth. The impact tour that hit the earth was probably 10 to 15 kilometers in diameter. So a monster. This created a huge lava lake. And it so it hit the Earth's crust, it hit that part of what is now North America 1.8 billion years ago, and it created this huge lava lake that then went through all of these magmatic processes that we're describing, these sort of Bowens reaction series-esque type things, and we get this segregation between this nickel sulfide, iron nickel sulfide liquids that have all the platinum group elements that have all the nickel in them. And so these layers, you get these kind of relatively thin layers of this magmatic segregation that then crystallized into an ore, a really economic mineral deposit to mine for nickel and platinum group elements. Do you have rocks from there? I do not have rocks from here, no.
SPEAKER_02Uh from the Sudbury Ignis complex?
SPEAKER_01Well, I've got ones from the the Target, the rocks that are still preserved that were just shocked but not melted. I have uh only a couple from the melt zone and none of the iron nickel sulfide ones.
SPEAKER_02I've got a couple of I actually have we you and I've never talked about this. I've been here for several times actually. The story goes back. You know, Jenny's dad worked for a company that they owned. There's a lot of water around there, lots of lakes and lots of islands, you know. Their company owned an island that had a kind of a mansion on it, and he got to use that once a week. And so we would go there and we had use of one of those flat bottom boats, you know, those skiffs, and and I would just I would take the boat out to these other areas, and I had my rock hammers and my chisels, and I was banging around all day while everybody else was fishing. I was rock collecting some rock. I was making a bunch of this stuff. Yeah.
SPEAKER_01I mean, yeah, Sudbury is all my grad students just went uh this past summer. Yeah, this past summer. They all took a trip, you know, they kind of raised some money for themselves and went up there and collected a bunch of samples. And it is one of the craziest geological locations. You you just get to see so many different types of amazing features. You go shatter cones and you get all these crazy granopheres and weird igneous rocks that formed inside of the impact layer. It's a really cool area and has a long history of mining up in the the Sudbury area as well. So that's another example. There's a similar one called the Vratafort structure in South Africa. That's another impact structure that produced these like iridium-rich and nickel and platinum group element enriched layers by this magmatic separation.
SPEAKER_02That's right. So, just to be clear, before we move on to the second way that that these things concentrated, that nickel ores concentrate, the example of the Sudbury Igneous complex, the meteor impact crater, created a lake that allowed for fractional crystallization, right? It allowed then these nickel-bearing elements to sink to the bottom of that lake.
SPEAKER_01Yep, that's exactly right. That's the gist of the story. A giant shallow magma chamber where all these separations and Bowens reaction series, et cetera, happened. So the laterite deposits, Chris, these are crazy ones. And these are, I would say, I would say they're kind of like up and comers, but not really. These are like they're the main event in the modern mining industry, I think, right now. Like this is where we get a lot of nickel from at the moment, is these laterite deposits.
SPEAKER_02And what these are is well, first of all, can I interrupt you a second, Jesse? Because I I want to just say that you said it's an up and comer, right? I kind of think about this in the same context as the mining for metals in sand, right? This kind of like new, it's a new look at how might nickel aggregate, how might it concentrate, right? And this is a really interesting one for me, I think. These laterite formations, these laterite soils.
SPEAKER_01If you I agree, this is just one of the crazier ways to form mineral deposits. Like I think the you know, magmatic processes, the magmatic separation, that kind of makes sense. That's intuitive. This is not so intuitive. And what these are these are weathering deposits. And so think of a soil profile. And we have a chapter, a couple chapters in the Camp Geo uh on the app that talk about soil, and you can see beautiful graphics that we've made of a soil profile. And you get you get different layers in a soil profile, and some are leaching layers and some are depositing layers and some are just organic layers. But in a soil profile, minerals are getting leached by the water passing through them, basically. I kind of like a coffee filter. I don't know. Is that a good do you probably have a better analogy?
SPEAKER_02Can I take a crack at it? I don't know. I wouldn't like, well, first of all, we're not talking about just any soil here, right? We're talking about the soil above the rock is it's ultramafic rock. We're talking about not a common surface exposure here, right? First of all, in order to have a laterite. And then you need the right climate for this. And weathering happens faster in a like a warm and humid kind of climate, right? But what happens then is these minerals that are high temperature minerals, because the root of this is ultramafic, they're not stable at the surface. And so the chemical weathering will leach out, it'll take out these inseparate elements like silicon and calcium and magnesium. They'll remove it from the rock, leaving the nickel behind. And it's concentrating it like that. It's like it's kind of like we're gonna take away a bunch of these minerals and get them out of the area, and we're gonna leave the nickel minerals behind and concentrate it that way. That's the way I think of this kind of laterite formation.
SPEAKER_01I think that's exactly right, Chris. And there's a whole bunch of, I think, really important geochemistry that goes on in these things or that helps inform us of how nickel can get enriched in this. So if you think about, well, Earth's carbon cycle, we've talked about the slow carbon cycle. And one of the main things about the slow carbon cycle is weathering calcium out of mafic rocks, taking it from pyroxene and putting it into the oceans, or taking it from feldspar and putting it into the oceans. And calcium is one that gets leached out pretty quickly. Magnesium also gets leached out pretty quickly. Now, you're left behind once you leach out silica and calcium magnesium, with those ones that are soluble in water, then you're left behind nickel, aluminum is another one, and iron kind of partially, and this is where we come back to the difference between nickel and iron. Iron, remember, can have two oxidation states. It can be plus two, plus three. One of them's mobile, one of them's not. Nickel only really exists in the plus two state, and so it kind of sticks there. Like aluminum, it sticks to mineral faces, it's not swept away, it's not dissolved in the water that's kind of filtering through the soil as easily. So it gets enriched and it could get moved up and down a little bit, but it doesn't get kind of carried away in the groundwater system. So it could move from like, you know, half a meter below the surface to a meter below the surface, but it's not going to get carried away out to the Amazon River system out into the ocean.
SPEAKER_02That's right. Back to your analogy of a pile of building bricks, right? If you have bricks of different color, you have red bricks and you have black bricks, right? And if chemical weathering preferentially removes the red bricks, you take them and get them out of that pile, you're concentrating the black bricks, and that's what's happening to the nickel. It's getting concentrated just because everything else is getting picked out.
SPEAKER_01That's exactly right, Chris. So what do we need for a laterite deposit? We need ultramafic rocks. We need the nickel around, right? And we talked about how nickel's not really present in granite. So you can leach the heck out of a granite and you're not going to form a nickel deposit. You need an ultramafic rock that has high nickel content at the surface, and you need that surface environment to be hot and humid, which means there's a lot of hot water around, which means that this leaching process happens more. So you need kind of tropical environments on top of ultramafic rocks. Okay, that's the laterite deposit. Let's end with talking about some of the more interesting approaches because we have this kind of impending nickel problem on our hands. Like we're going to need more nickel. There's demand growing. But I want to touch on this laterite deposit thing, Chris, because Indonesia is a country that has dramatically increased its nickel production. And actually, it is the largest producer of nickel. And the Philippines are another massive producer of nickel. Now, makes sense. Two questions. Why does it make sense? Why does it make sense? And then I want to ask a question.
SPEAKER_02Okay, provided then Indonesia and the Philippines have if they have ultramafic rock exposed at the surface, they're prime for forming laterite soils then, because they're really warm and they're super, super humid. And so the it's going to be accelerated chemical weathering. Exactly. And it's going to then concentrate that way.
SPEAKER_01So my question then, Chris, so that that's exactly right. I mean, these are just huge laterite deposits. They're tectonically active areas. These are arcs, uh, volcanic arcs that have a whole bunch of magmatism going on, tectonics thrusting stuff up. So you get ultra mafic rocks at the surface in a human environment. If you were gonna open a nickel mine right next door to your house, which one would you rather have? A laterite deposit or a magmatic iron nickel sulfide deposit? I guess what I'm asking is which one would you imagine is more environmentally damaging or friendly?
SPEAKER_02That really, really good question. So before I even attempt to answer that question, how would they go about mining a laterite nickel deposit then? Like I need to know that first, right?
SPEAKER_01Yeah, fair, fair point, fair point. It's a uh it's not that environmentally friendly, let's say. I mean, you think of a soil horizon, it's it's not gonna be that thick, it's gonna be a couple meters, but it's over a huge wide area, right? So you have this relatively low concentration over a huge area, you're basically gonna have to clear cut and either dig up soil over a huge area, or sometimes just dump acid through the soil and and leach it out that way. So it can be really damaging.
SPEAKER_02Okay. So do you do you want me to answer the question then? Because I think I'm gonna get it right now.
SPEAKER_01Well, let me add one thing to it because I I think um mining these iron nickel sulfides is not necessarily the best either.
SPEAKER_02And and yeah, I don't think either one is gonna be like environmentally really good. Any sulfide and arsenic kind of thing, those those words just don't sound good to me.
SPEAKER_01No, they're they they they yeah, and there's a huge legacy, like for instance, up in Sudbury, Chris. When you go up there, I mean you saw the area is just completely blown apart by acid rain. Like there's hardly any vegetation. Now it's starting to recover, but like there's a legacy of environmental damage in Sudbury because of this mining, for sure.
SPEAKER_02But I'm telling you, too, when you crack open some of these rocks, the it stinks. Like your hands, they they don't smell good. They've got this residue on them. I mean, it's just it's not a pleasant. As soon as I collected the rocks, I bagged them up and and washed my hands as quickly as I could. Because I just like I mean, totally you know that you're not handling something intuitively, you're not handling something that is probably good for you.
SPEAKER_01Totally. And so I uh you know, the to answer the question, it's sort of like, well, neither. I mean, I it if I had to choose, I'd probably rather have one of the iron nickel sulfide deposits, the magmatic ones, because that is more like quarrying. You can kind of contain it, you don't have to scrape off soil from a huge, huge area, but neither one really would be great. And nickel has one of the highest carbon costs for mining out there. Nickel, the element, is just it's carbon expensive to mine. And so there are all of these really interesting approaches that people are trying to get nickel out. And one of the most interesting is biomining. Basically, I think of it as using microbes or plants to concentrate nickel.
SPEAKER_02They'll do the same thing that happens in a laterite kind of environment like Indonesia or the Philippines, right? But they're gonna use microbes to do it instead of natural chemical weather and processes. Exactly. And you can do they're gonna liberate these. Minerals out and leave the nickel behind, thereby concentrating and aggregating it in more.
SPEAKER_01And you can kind of do the same thing with crops. You know, there are certain crops that soak up nickel, and you they use it's a bioactive element, so they soak up nickel. You harvest the crops, extract the nickel from the crops.
SPEAKER_02Isn't that weird? You're talking about taking the nickel out of the plant itself. That's crazy. That yeah, that's super interesting. You sent me a couple article links to read and you know, to get ready for this, and I was absolutely enthralled by this biomining kind of thing.
SPEAKER_01It's a really, really um it's a cool one. And I think it kind of comes back to well, it kind of comes full circle. We're talking about the same chemical reaction a lot. In a lot of our conversations, Chris, that we have about the green energy transition. We're talking about taking ultramafic rocks, putting them at the surface, and weathering those things. And that does a couple things. It draws down CO2, we can liberate nickel from them. There's a lot of energy stored in that reaction, and and it produces things like hydrogen. It can produce geological hydrogen. So there's a lot of interesting stuff about ultramafic rocks at the surface, I think, here.
SPEAKER_02I wonder, Jesse, about let's say that you had this kind of ultramafic magmatic ore, and you mine the nickel out of it. And what then could we do if we pulverize the rest of this ultramafic rock? That seems to be really useful then in terms of like sequestering carbon. Right. Are we doing that?
SPEAKER_01Exactly. There are companies that are proposing to do just that. Take that ultramafic rock and use it to store CO2. That reaction, that serpentinization reaction that stores CO2 also liberates hydrogen. So you can capture maybe the hydrogen gas. So there's kind of like one reaction to rule them all here or something. Uh there's just a lot of focus on ultramaphic rocks at the surface because it can be really bad if it's uncontrolled, but we can do a lot with this reaction, with this type of rock at the surface. We can extract stuff from it, we can sequester CO2 into it. It's a really interesting space, I think, to pay attention to for the next several years here. I just feel like we've talked about that quite a bit, or it's kind of come up in a couple different ways.
SPEAKER_02From our Earth's climate book that we talked about, that's I was just gonna say that like uh the last chapter in our climate book, we do a whole session on carbon sequestration, and this was one of the things that we talked about, although not in this exact context, but something very similar to that.
SPEAKER_01Yeah, very similar, exactly, very similar. So I I don't know, Chris. I think this this sort of phytomining or paying attention to to how we're using this stuff or how we're how people are maybe trying to tackle a couple problems with one rock type and one reaction at the surface is cool to pay attention to. It's a good time to be a geologist. I agree.
SPEAKER_02You know, that's just smart in terms of these the biomining, this phytomining, using plants to do the it's um incredibly, I think, clever. I don't that that's probably not the right word for, but it's just um it's so smart, it's so out of the box.
SPEAKER_01Yeah, so completely out of the box, yes. And and really, really you know, interdisciplinary. It takes the biologists working together with the chemists, working together with the geologists, working together with like the water people, the Andrew Dewitz of the world, the the geo what is it, fluvial geomorphologists. They gotta they gotta pay attention to the phone.
SPEAKER_02He is a fluvial geomorphologist, yeah.
SPEAKER_01I know pinky in the air.
SPEAKER_02Oh man. Well, hey, Jesse, I think that's a wrap. Do you have anything else you want to add to this to top it off, or are we good to go?
SPEAKER_01I think I think that's a that's a wrap on the devil's metal. I mean, just what a fun name. All right. And really, you know, fun geology, totally fun geology in here. I I I loved it. So hey, with that, send us an email. We got a lot of uh really interesting questions from from you guys and uh keep sending them our way. Send us an email, planetegeocast at gmail.com. You can go to our website, planetgeocast.com, there you can subscribe. You can support us. Hey, we always appreciate it when you go there. There's a support us link. We always appreciate it when people send us a bit to help support this podcast. The other way you can support us is head over to our Camp Geo app. You can download that in the app store, or it's the first link in your show notes. We have all of our Camp Geo content. That's audio discussions Chris and I put together with images that I think are really, really useful for learning uh the basics because some of this stuff is complicated. You just need the image there to take a look at it and then continue listening to the discussion. We also have several audiobooks on there that you can purchase as well, including the Earth's Climate Book, which is there for a couple bucks. Cheers. Peace.