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Mass Confusion - How to Name a Mineral · PlanetGeo: The Geology Podcast

0:02
SPEAKER_00: Welcome to Planet Geo, the podcast where we talk about our amazing planet, how it works, and why it matters to you.
0:11
SPEAKER_00: Christopher Mr.
0:14
SPEAKER_00: Chapstick Bohois.
0:16
SPEAKER_00: What's going on?
0:16
SPEAKER_01: Hey, you can't can't have dry lips, Jesse.
0:19
SPEAKER_00: Especially not when you're recording Planet Geo.
0:22
SPEAKER_01: No, you can't have that at all.
0:24
SPEAKER_00: That would be unacceptable sound quality.
0:27
SPEAKER_00: I'm doing great.
0:27
SPEAKER_00: How are you?
0:28
SPEAKER_01: I am doing great.
0:30
SPEAKER_01: It's a rare, beautiful day outside in West Michigan today.
0:33
SPEAKER_01: So it is, yeah, it's I'm doing okay.
0:35
SPEAKER_00: That's good, man.
0:36
SPEAKER_00: Well, I'm uh, you know, happy you're you're choosing it to spend it indoors in your little home recording booth here with me talking about geology.
0:44
SPEAKER_00: Uh, but we just saw each other recently in live and in person.
0:48
SPEAKER_00: That was really fun.
0:49
SPEAKER_00: It's good to get together.
0:50
SPEAKER_00: It was.
0:50
SPEAKER_00: It's been a while since we've done it.
0:52
SPEAKER_01: Yeah, we were invited to speak to my alma mater.
0:55
SPEAKER_01: Grand Valley State University brought us in.
0:57
SPEAKER_01: The um the AAPG, the American Association of Petroleum Geologists Club, yeah, invited us in to speak.
1:05
SPEAKER_01: Yeah.
1:06
SPEAKER_01: So I don't know.
1:07
SPEAKER_01: That was kind of it was interesting, right?
1:09
SPEAKER_01: We here we are.
1:10
SPEAKER_01: Here you and I sitting in comfy chairs up on a stage in the auditorium giving a talk about geoscience education.
1:17
SPEAKER_00: What a world, what a world.
1:18
SPEAKER_00: So yeah, that that leads us kind of nicely into what we're doing today because we didn't exactly know how long we would uh talk for or how many questions we would get.
1:27
SPEAKER_00: And so we had scripted out an episode that we could have recorded live, but knowing us, we got a little bit maybe long-winded, but I think it was good.
1:37
SPEAKER_00: It was all useful stuff, and we had a lot of questions from people.
1:40
SPEAKER_00: But we the point is we didn't get to record this episode, so that's what we're doing now.
1:44
SPEAKER_00: We're just sitting down, we're recording this episode because I think it's a really kind of cool, relatively short, but really cool and important topic.
1:52
SPEAKER_01: Well, yeah, I mean the title of it is Mass Confusion How to Name a Mineral.
1:56
SPEAKER_01: Um it is uh it's an interesting topic.
2:00
SPEAKER_01: I uh you know, it really is, but you posted uh an article here in the script here, and I opened it up.
2:06
SPEAKER_01: And these rules for naming a mineral, oh my gosh, nobody wants to read that, Jesse.
2:12
SPEAKER_01: I'm like it is when you open it up, it is it's a PDF, it's long, there are no paragraphs in it.
2:19
SPEAKER_00: It's just it's brutal, it's just it's brutal.
2:21
SPEAKER_00: Pages and pages of single space text, 12-point font.
2:25
SPEAKER_00: I mean, horrible.
2:26
SPEAKER_00: So I we're what we're gonna try and do here, I think, Chris, is kind of distill this down into what matters a little bit.
2:32
SPEAKER_00: And I kind of like this episode because there's a lot, especially in the last couple years, there have been a lot of news articles written about new minerals discovered or named.
2:43
SPEAKER_00: And you and I have had this conversation about, you know, how how do people, a lot of people who listen to this podcast, read those like geoscience news articles, you know, Science Daily, um, I don't know, name any of the sort of science news aggregator websites.
2:57
SPEAKER_00: A lot of people will read those press releases, send us questions about some of them.
3:01
SPEAKER_00: And I think what kind of what we're hitting on here is part of the theme of like how do you read those or what do those mean?
3:07
SPEAKER_00: Like, how important are they?
3:08
SPEAKER_01: Yeah, so it's interesting.
3:10
SPEAKER_01: You're more into the how to name a mineral thing, but when we started scripting this out, my interest went instead more towards the discovery of the new minerals themselves.
3:22
SPEAKER_01: How are we still discovering new minerals?
3:24
SPEAKER_01: And that's going to be a part of this episode too.
3:26
SPEAKER_00: Yeah, that's exactly right.
3:27
SPEAKER_00: And those are sort of the two things we're going to talk about in this episode is what does it take to kind of name a new mineral or discover it for that matter?
3:35
SPEAKER_00: What does it mean?
3:36
SPEAKER_00: And you know, sort of why is it important?
3:37
SPEAKER_00: What does it tell us about the earth?
3:38
SPEAKER_00: But I think we have to back up a minute and start with the definition of a mineral.
3:41
SPEAKER_00: Because as you said, there's this huge PDF document.
3:44
SPEAKER_00: There's it's a very pedantic thing.
3:46
SPEAKER_00: Like, what is a mineral?
3:47
SPEAKER_00: How do you define it?
3:48
SPEAKER_00: All that stuff.
3:49
SPEAKER_00: But there's some basics, right?
3:51
SPEAKER_00: And you cover these every year to all of your geoscience students.
3:53
SPEAKER_00: Like, what are these basics and how do you explain them to your students?
3:57
SPEAKER_01: Uh so there are five very specific type criteria for something to be classified as a mineral.
4:03
SPEAKER_01: Where, you know, you talk about rocks.
4:05
SPEAKER_01: Rocks is a very loose definition, but minerals is not.
4:08
SPEAKER_01: You know, it has to be these five things.
4:10
SPEAKER_01: So think about those.
4:11
SPEAKER_01: You know, if you're sitting there listening to this episode, what are those five things?
4:15
SPEAKER_01: See if you remember back to you know your high school years or if you took some classes in college or whatever.
4:21
SPEAKER_01: But this is in no particular order, but this is just kind of the way that my mind runs through it.
4:26
SPEAKER_01: Um, it in order for something to be a mineral, it has to be a solid, it has to be naturally occurring, which that one is, I think you would say naturally occurring is the most important one, I think, right?
4:39
SPEAKER_01: Is that is that a fair statement?
4:41
SPEAKER_00: Yes, it'll sort of be front and center in our conversation today.
4:44
SPEAKER_00: That's that's the one we're gonna talk about the most.
4:46
SPEAKER_00: Absolutely.
4:47
SPEAKER_01: Yeah, the third thing is that it has to be inorganic, and this one, you know, this might go away soon.
4:54
SPEAKER_01: I mean, we we interviewed a while back Gabriela Farfan, who is a curator at the Smithsonian, and she said that this one out of there might come a time, kind of like how Pluto got demoted a number of years ago, you know, it's no longer a planet, now it's a dwarf planet.
5:11
SPEAKER_01: That's right.
5:13
SPEAKER_01: So it might be four in the future.
5:15
SPEAKER_01: We don't we don't know.
5:16
SPEAKER_01: Well, that remains to be seen.
5:17
SPEAKER_01: But the fourth criteria for something to be a mineral is it needs to have a definite chemical composition.
5:23
SPEAKER_01: And what we're talking about, like this, is if the mineral is SiO2, silicon dioxide, then that mineral is going to be quartz.
5:30
SPEAKER_01: NaCl is halite.
5:31
SPEAKER_01: These are very simple formulas.
5:33
SPEAKER_01: What my simple mind can memorize and recall.
5:36
SPEAKER_01: Right.
5:36
SPEAKER_00: Uh, don't ask me what biotite is, but I mean I know it has some magnesium and iron in it, and silica probably and oxygen, but you know, a whole bunch of stuff added in there.
5:46
SPEAKER_01: And then lastly, in order for something to be a mineral, it has to have a definite crystalline structure.
5:52
SPEAKER_01: So all five of those things right now have to be met.
5:55
SPEAKER_01: The last one, the definite crystalline structure, is more four and five are related to each other.
6:01
SPEAKER_01: Because there's a definite chemical composition, there's one best way to stack those elements together, and nature finds that best way under the pressures and temperatures that exist.
6:13
SPEAKER_01: And so you get this definite, consistent crystalline structure.
6:18
SPEAKER_00: Yeah, and I think another way or something that I talk about in in the geoscience class that I teach at Penn State is you can think of this word definite, like a definite chemical composition and a definite crystalline structure, as unique.
6:31
SPEAKER_00: They have to have a unique chemical composition and unique crystalline structure.
6:36
SPEAKER_00: And what that means is those both have to be unique.
6:38
SPEAKER_00: So there are other minerals that have the same formula SiO2 that are not quartz.
6:44
SPEAKER_00: There are things that are higher temperature, different pressure conditions they are formed in.
6:48
SPEAKER_00: They have a different chemical structure.
6:51
SPEAKER_00: The same thing goes, there are minerals that share a crystalline structure, but have different chemistry inside of it.
6:56
SPEAKER_00: Different elements go into the same structure.
6:59
SPEAKER_00: So that's where this gets this nuanced uh discussion.
7:03
SPEAKER_00: And we're gonna focus, I think the end of our conversation will focus on that a lot.
7:07
SPEAKER_00: Having the combination of a unique chemistry and a unique crystal structure.
7:11
SPEAKER_00: That's what sets a mineral apart from other minerals that have similarities to it.
7:16
SPEAKER_01: That's right.
7:16
SPEAKER_01: So, Jesse, you you said earlier that we're discovering new minerals.
7:20
SPEAKER_01: Let's jump into that first before we get into the specifics of naming a mineral.
7:25
SPEAKER_01: Let's talk a little bit about where new minerals are commonly found.
7:29
SPEAKER_01: Because, like you said, we're getting flipped articles quite a bit by our listeners about hey, did you see this and did you see that and so on?
7:35
SPEAKER_01: And so we kind of narrowed it down to three places or settings where new minerals were being discovered, right?
7:43
SPEAKER_01: Is that a fair assessment?
7:44
SPEAKER_00: Okay, so roughly, yes, yeah, absolutely.
7:47
SPEAKER_01: We we're finding new minerals associated with diamonds or in diamonds as inclusions, right?
7:54
SPEAKER_01: As impurities within the diamond.
7:56
SPEAKER_01: We're finding them also in meteorites, and also we're finding them from the moon, source from the moon.
8:06
SPEAKER_01: Okay, so let's talk about these.
8:07
SPEAKER_01: Well, like, why are these three the common places where we're discovering new minerals yet today?
8:16
SPEAKER_01: What's going on?
8:17
SPEAKER_00: One way to think about this would be to say, well, okay, if I told you, hey, we discovered a new mineral, where would you where would your like instincts say, oh yeah, okay, I I think it might be discovered in this location?
8:28
SPEAKER_00: And I I think these three categories, well, at least two of them, the moon and meteorites, those kind of make intuitive sense.
8:34
SPEAKER_00: Like if you're gonna find something new, something weird, something strange, it might be an abnormal rock, like a unique rock that we have on Earth, which is meteorites in many of many cases.
8:45
SPEAKER_01: I get that.
8:46
SPEAKER_01: However, meteorites have been they're not new.
8:49
SPEAKER_01: I mean, we've been studying meteorites for quite a while, and also it's been a long time since we've gotten direct samples from the moon.
8:56
SPEAKER_00: That's true.
8:57
SPEAKER_00: That's true.
8:58
SPEAKER_00: And so I think one thing is we just keep exploring these old samples, like the the Apollo mission return samples and meteorites.
9:06
SPEAKER_00: New meteorites are landing every day, but actually more are being discovered.
9:09
SPEAKER_00: You know, some land, they go into private collectors' pockets, and then they sort of come back out, or pieces of them kind of get sold off into the research space, so researchers kind of look in detail.
9:20
SPEAKER_00: So like old meteorites are newly worked on quite frequently.
9:23
SPEAKER_00: But I think the more important thing is that most of the minerals on Earth we've looked at.
9:27
SPEAKER_00: Now, there are new minerals being discovered on Earth all the time, too, but we have Earth pretty well covered.
9:33
SPEAKER_00: There's like 6,000 or 7,000 minerals on Earth that have been described and documented, and some incredibly rare ones have been found too.
9:41
SPEAKER_00: So we've kind of explored the surface, keyword surface of our planet quite well.
9:47
SPEAKER_00: Yeah.
9:47
SPEAKER_01: And so that's why the idea of discovering new minerals in association with diamonds, right?
9:56
SPEAKER_01: Because diamonds are brought from deep within the mantle, and they're brought under very certain circumstances, and you know, we'll talk about that in just a second.
10:06
SPEAKER_01: But diamonds are extremely high pressure, they come from deep inside the earth.
10:11
SPEAKER_01: So, how do they get brought to the surface?
10:15
SPEAKER_01: We talked about this a long time ago, Jesse.
10:17
SPEAKER_01: With uh we did an episode, I think it was in season one, maybe two and a half years ago.
10:22
SPEAKER_01: Yeah, no, this was like one of our first diamonds, yeah.
10:24
SPEAKER_00: First five or six episodes, I think.
10:26
SPEAKER_00: Yeah.
10:26
SPEAKER_01: That's right.
10:26
SPEAKER_01: And this is near and dear to your heart.
10:28
SPEAKER_01: I mean, you you know a lot about this, you've studied a little, I think it goes back to probably your time in Alberta.
10:34
SPEAKER_01: But let's get into that a little bit.
10:35
SPEAKER_01: How do we get a look at deeper down in the mantle?
10:39
SPEAKER_00: So let me just uh back up really quickly, Chris, and just get a definition in here because we're saying discover a lot, like, oh, we discover new minerals.
10:47
SPEAKER_00: And that we're gonna get into this because that's a nuanced sort of term.
10:50
SPEAKER_00: There's a difference between discovering a new mineral, like finding something that has a different chemistry than we ever thought could exist, or a different mineral structure than we thought could ever exist, and finding something that we did not know existed before.
11:02
SPEAKER_00: That's sort of discovery, I think.
11:05
SPEAKER_00: What we're talking about frequently here is naming a new mineral.
11:10
SPEAKER_00: And in order to name a new mineral, we have to have a natural example of it.
11:15
SPEAKER_00: And this is where this diamonds as a recorder of the deep earth becomes important because several of the minerals we're gonna talk about next, we've known that they exist in the earth for a long time, since the 60s or since the 70s, but we've never found a natural, naturally occurring, naturally formed piece of that mineral.
11:35
SPEAKER_00: So we can synthesize it in the lab.
11:37
SPEAKER_01: Now that begs the question.
11:38
SPEAKER_01: I gotta stop you there because then if we we've never seen them in a natural setting, we've been able to create them in a lab, but we've never seen them in a natural setting.
11:46
SPEAKER_01: How then did we know with no uncertainty that these minerals existed in nature?
11:53
SPEAKER_01: How do we know that?
11:55
SPEAKER_00: Great question.
11:56
SPEAKER_00: Because you can synthesize this in the lab.
11:58
SPEAKER_00: So our lab technicians, you came to the Carnegie Institution of Science when I was there as a postdoc, and you saw these huge presses that do these pressure experiments, these really high pressure experiments.
12:09
SPEAKER_00: Think basically you take a big piston and you put a rocket between two pistons and you can squeeze that to really high pressure.
12:17
SPEAKER_00: Like any pressure you can put on those pistons, you can put it in the city.
12:19
SPEAKER_01: So in other words, they're replicating the conditions deep inside the earth.
12:22
SPEAKER_01: Exactly.
12:23
SPEAKER_00: And these get really complicated.
12:24
SPEAKER_00: Like Chris, you saw the big press that what's called a multi-anvil press, that it's fills up a room.
12:29
SPEAKER_00: I mean, it fills up a three-story height room.
12:32
SPEAKER_00: It's a huge press.
12:34
SPEAKER_00: And so that puts a lot of pressure on these minerals.
12:36
SPEAKER_00: But actually, the higher pressure, the highest pressures we get are very tiny little things where we take a tiny, tiny microscopic sample of a rock, squish it between two diamonds, so gem quality diamonds.
12:48
SPEAKER_00: You think of a diamond in your ring, and has that point on the bottom.
12:51
SPEAKER_00: So it has this point there.
12:53
SPEAKER_00: If you cut off the point, very small piece of the point, and you put two diamonds with their points cut off facing against each other, kind of the diamond points pointing towards each other, put a rock in between there, and you can get this to incredibly high pressures that replicate the deep, deep, deep earth.
13:08
SPEAKER_00: And so what people have done since the 60s or in the 70s and 80s throughout uh geologic research history have replicated the interior of the earth, the pressure-temperature conditions in the interior of the earth through these experimental techniques.
13:23
SPEAKER_01: So okay, so let me back this up a second then.
13:26
SPEAKER_01: Basically, what you're saying is if we know the chemical composition of deeper down into the earth, we know ratios and and chemistry, then we can replicate those conditions in a lab and create these minerals.
13:41
SPEAKER_00: Exactly right.
13:42
SPEAKER_00: Good assumption.
13:42
SPEAKER_00: Perfect, perfectly.
13:44
SPEAKER_01: First of all, Jesse, review these Kimberlite pipes, these are these deep-rooted volcanic eruptions that are quite small, actually, quite rare and quite small.
13:56
SPEAKER_01: No human has ever witnessed one of these eruptions.
13:58
SPEAKER_00: Definitely not.
13:59
SPEAKER_01: They as these deep-rooted volcanic eruptions rise up through the mantle, they kind of tear up then.
14:06
SPEAKER_01: Um, kind of like if you're sick, you get this phlegm in your throat and you kind of cough, you know, there's so it's it's kind of coughing up and ripping up parts of the mantle and bringing it with them.
14:16
SPEAKER_01: That's how diamonds get brought to the surface.
14:19
SPEAKER_00: Good.
14:19
SPEAKER_00: That's absolutely right.
14:20
SPEAKER_00: So basically, these things that you're that coughing rips up everything, diamonds and all sorts of other stuff.
14:26
SPEAKER_00: Diamonds are, however, very, very chemically and physically non-reactive.
14:33
SPEAKER_00: So they're these little chemical capsules.
14:35
SPEAKER_00: So the diamonds come up and they don't really get modified by the magma too much.
14:40
SPEAKER_00: They remain chemically and physically intact.
14:43
SPEAKER_00: And so the diamond itself is coming from very deep.
14:46
SPEAKER_00: We have lots of samples of diamonds, so that's not a new mineral.
14:49
SPEAKER_00: But the diamonds also, when they're growing, grow around other minerals as they're growing.
14:56
SPEAKER_00: So you kind of think you gotta picture a what's the best analogy here?
15:01
SPEAKER_00: So you picture deep down in the mantle, the whole thing is solid, but you inject some of this like CO2-rich fluid, which people think diamonds kind of crystallize from.
15:09
SPEAKER_00: So you got this fluid that's kind of percolating through little cracks, and the diamonds grow from that fluid, so they're slowly growing from that fluid.
15:18
SPEAKER_00: And sometimes there'll be little other minerals around, and the diamond will be.
15:40
SPEAKER_00: So that's what we call an inclusion.
15:42
SPEAKER_01: And sometimes you can actually see these.
15:44
SPEAKER_01: In fact, this is what determines the quality of a gem quality diamond is the the less inclusions that a diamond has, the more it's gonna play with light, you know, because think of these dark, almost black inclusions inside of a diamond.
15:57
SPEAKER_01: That's gonna mess around with the way diamonds are gonna, you know, make the light kind of dance around inside.
16:03
SPEAKER_01: And so if you put a you know, a lower quality diamond under a microscope, you can easily see these inclusions inside of a diamond.
16:12
SPEAKER_01: All diamonds have them.
16:13
SPEAKER_01: It's just a matter of like the degree to which they have these inclusions.
16:17
SPEAKER_01: And again, if you have a diamond at home, you can take it, put it under even a 10x uh magnifying glass, and you can see these inclusions inside of it.
16:25
SPEAKER_01: But it's pretty easy.
16:26
SPEAKER_00: Yeah, so these inclusions, so that the diamonds have these inclusions sometimes, sometimes they don't have any inclusions, and then they're really great gem quality ones.
16:33
SPEAKER_00: But uh many diamonds are not gem quality and they have inclusions in them.
16:37
SPEAKER_00: Those inclusions are from the deep earth, and they've kind of been transported up in this chemical pressure capsule, this time capsule that records what's down deep in the earth.
16:48
SPEAKER_00: Because if you just took a rock, if we took so Chris, we're gonna start talking about the depths here a minute.
16:53
SPEAKER_01: So let me just let Can we talk about the specific, let's talk about the specific mineral, bridge minite.
16:59
SPEAKER_01: Let's let's transition into that, okay?
17:02
SPEAKER_01: All right, Jesse, let's just let's ask our our audience a second, what is the most common mineral on the planet?
17:10
SPEAKER_01: And you know, most people are gonna say feldspar, right?
17:15
SPEAKER_01: I mean, that it's the most common mineral that's on the crust of the earth, and it is the most common mineral that's on the surface of the earth, but what is the most common mineral on the planet?
17:26
SPEAKER_01: Most people have never heard of you know, most people have never heard of bridgmanite.
17:32
SPEAKER_00: Right.
17:32
SPEAKER_01: But that's absolutely that is the most common mineral on the planet.
17:38
SPEAKER_00: So bridgmanite, and this is one of these like sort of fantastic things that is just kind of shocking to me still, is that bridgmanite is the most common mineral on earth, in earth.
17:50
SPEAKER_00: Most common mineral in earth.
17:51
SPEAKER_00: And it was not named, we did not have a natural piece of it until 2014.
17:57
SPEAKER_00: So we knew this thing was the most common mineral.
18:00
SPEAKER_00: We knew it was the most common mineral in Earth since the 60s because of these experiments that I was talking about, but it was not named, we didn't have a natural piece of it until 2014.
18:10
SPEAKER_00: So here's how this works.
18:12
SPEAKER_00: So let's take the mantle.
18:14
SPEAKER_00: The mantle composition, that the sort of layer of earth that is this big silicate-rich layer, the composition of that is a rock that we would call peridotite on the surface.
18:25
SPEAKER_00: So peridotite on the surface is olivine and pyroxine dominantly, usually two different types of pyroxene in a pyritotite, but it's an ultra mafic composition.
18:36
SPEAKER_00: So it's super dark.
18:38
SPEAKER_01: So let's back up a second, just for review purposes, right?
18:41
SPEAKER_01: The rock granite, everybody knows what granite looks like.
18:44
SPEAKER_01: Granite is light-colored, it's it's what we call felsic, okay?
18:47
SPEAKER_01: And that means it's a light-colored rock with which has up to 15% black minerals, dark flex in it, and so on.
18:54
SPEAKER_01: The opposite of that is the rock basalt, and basalt is what makes up most of the ocean floor.
19:00
SPEAKER_01: And basalt is black, it's fine-grained, it's extrusive, and it's what we call mafic.
19:05
SPEAKER_01: So, what you said about peridotite, which comes out of the mantle, which a long, long time ago in an episode in probably seasonal one, we talked about the mantle is ultramafic.
19:14
SPEAKER_01: So it's it's like it's mafic on steroids.
19:17
SPEAKER_01: Okay, so just for review purposes, that's what we're talking about.
19:21
SPEAKER_01: That's peridotite and it's ultramafic.
19:25
SPEAKER_00: And it's super rich in iron and magnesium, and so has lower silica than the other one, so it has tons of magnesium and iron in it.
19:32
SPEAKER_00: It is this ultramafic composition.
19:34
SPEAKER_00: Now, if you take a pritotite, at the surface, pritotite, the rock, would be olivine, clinopyroxine, and orthopyroxine, two kind of brown, greenish minerals, it'd be really dark green, and olivine's kind of a pretty green and olive green, and so that's what it would look like.
19:49
SPEAKER_00: Now, if you took that pryotite and you put it 600 kilometers down deep in Earth and at the temperature that exists at that depth, which is quite hot, what would happen to it?
20:00
SPEAKER_00: Well, the minerals, olivine, clinoperxine, orthopyroxine, are not stable at that depth.
20:07
SPEAKER_00: The mineral structure becomes unstable because the pressures are too high.
20:11
SPEAKER_00: So what happens is you get this mineralogical conversion.
20:15
SPEAKER_00: You get a couple different minerals.
20:17
SPEAKER_00: One we call ferropericlase, one we call calcium perovskite, which actually is a new name.
20:23
SPEAKER_01: Coachese, hey, quit quit dropping big terms here just to get to the point.
20:28
SPEAKER_00: Okay, we form Bridgmanite.
20:30
SPEAKER_00: The point is you form Bridgminite and you form a lot of Bridgminite.
20:33
SPEAKER_00: Bridgminite will make up like eighty percent of the rock.
20:35
SPEAKER_01: Hold on.
20:35
SPEAKER_01: I'm I'm gonna interrupt you, Jesse.
20:37
SPEAKER_01: All right, listen.
20:38
SPEAKER_01: The chemical composition of olivine is MGFE SIO4.
20:46
SPEAKER_01: Okay, and that is a very common mineral in the upper mantle.
20:51
SPEAKER_01: Okay.
20:52
SPEAKER_01: But we're talking about deeper in the mantle, and you're talking about bridmanite, which is Mg SiO3.
20:59
SPEAKER_01: So it has the same elements, and as you just said, it has a different crystalline structure than olivine does, but it also has a slightly different chemical composition.
21:09
SPEAKER_01: Can we talk about that a minute?
21:11
SPEAKER_01: Why is there a slightly different chemical composition?
21:14
SPEAKER_01: Is it a matter of what can fit in the crystal structure at this depth, or is it a matter of the ratios of the elements present?
21:22
SPEAKER_00: It's a combination of both.
21:23
SPEAKER_00: So it would be, you know, you described it as this recipe for making minerals, you know, at the surface with the given amount of magnesium, iron, silica, oxygen, aluminum, all that stuff that is in a rock, with that chemical makeup, that chemical recipe in the mantle, not at the surface, but in the mantle, olivine, clinopyroxine, orthopyroxine are the stable combination there.
21:45
SPEAKER_00: When you go really, really deep down, those minerals are not stable, they start to break down, and you need to rearrange.
21:51
SPEAKER_00: So we have this recipe, this soup of elements, and they need to be rearranged in a stable form.
21:56
SPEAKER_00: And so it's kind of a combination.
21:57
SPEAKER_00: We have this fixed recipe, we know what's The recipe is, and those elements kind of arrange themselves in the most stable group of minerals that they can.
22:06
SPEAKER_00: And bridgement happens to be very stable, it has a magnesium, silica, and oxygen, so those are very common elements.
22:13
SPEAKER_00: So we end up making a lot of bridgemonite in this process.
22:16
SPEAKER_00: And then the things that don't fit into bridgement go into other minerals that are stable at those extreme depths.
22:22
SPEAKER_01: And also it's important to note, too, that within the mantle, this portion of the mantle that has bridgement is extremely thick.
22:31
SPEAKER_01: It occurs over a pretty wide range of conditions, but it's going to be deeper down than where olivine can exist.
22:39
SPEAKER_01: So when we see peridotite on the Earth's surface, this peridotite does not contain bridgemenite, it contains olivine and these other minerals that you alluded to before.
22:49
SPEAKER_00: Exactly.
22:50
SPEAKER_00: And if we go back to the diamond and Kimberlite story, if those Kimberlites were erupting from deep, deep down where bridgminite might be stable and diamond is stable.
23:00
SPEAKER_00: But if we took a block of rock, if that cough of the Kimberlite coughed up some phlegm from really deep down in the mantle and grabbed some of this peridotite that has bridgemenite in it, that bridgemonite will react out very, very quickly because it's so unstable at the surface.
23:15
SPEAKER_00: It loves high pressures, it does not like low pressures, and it'll change really, really quickly.
23:21
SPEAKER_00: It kind of becomes unstable quite quickly.
23:23
SPEAKER_00: So if you have a rock that erupts into Kimberlite, we're not going to find any bridgmanite in it.
23:29
SPEAKER_00: Because the bridgemenite's unhappy on its way up.
23:31
SPEAKER_00: As it transits the crust, it kind of breaks down.
23:34
SPEAKER_00: So what we need is to find a diamond that grew around a piece of bridgemonite that preserves it all the way to the surface.
23:41
SPEAKER_00: And that's exactly why it took us so long to find a piece of natural bridgemenite, even though it is the most common mineral in Earth.
23:48
SPEAKER_01: Well done.
23:49
SPEAKER_01: I like the way you put that with the comparison of the way diamonds get brought to the surface and the way rocks get brought to the surface, two very, very different processes going on.
23:58
SPEAKER_01: And that makes a lot of sense.
23:59
SPEAKER_01: All right, Jesse.
24:00
SPEAKER_01: So listen, I think we should transition into then naming of minerals.
24:05
SPEAKER_01: Okay, how's this done?
24:06
SPEAKER_01: What are the rules?
24:08
SPEAKER_01: Let's, you know, let's kind of keep this tight here, but let's go through this a little bit because I think it's important.
24:12
SPEAKER_00: I think so too.
24:13
SPEAKER_00: I mean, it basically when you so let's say 2014, you know, some scientists they found a diamond that had this Bridgemanite in it, but it had not been named Bridgeman Knight yet, because when they discover the natural example of this mineral that we all knew existed, now they're allowed to name it because they've discovered they've found the first natural occurring example of it.
24:31
SPEAKER_00: And this is what's happened in the last couple years.
24:33
SPEAKER_00: This is what a bunch of press releases have come out over the last, I don't know, several years.
24:38
SPEAKER_00: Uh, you'll see this probably pretty frequently, actually, if you start looking in the news articles and pay attention to this, is that people find a naturally occurring example, they get to name it.
24:47
SPEAKER_00: Now, it's frowned upon to name it after politicians.
24:50
SPEAKER_00: Basically, you have to like submit this whole thing.
24:52
SPEAKER_00: You have to submit the chemistry, you have to submit the structure, you have to identify and submit all this information, and then you propose a name, and it goes to this naming commission where people, you know, sort of sit around and say, okay, is this a unique mineral?
25:04
SPEAKER_00: Is this a unique crystalline structure?
25:06
SPEAKER_00: Does it fit the definition of a mineral?
25:08
SPEAKER_00: And if so, is the name appropriate?
25:11
SPEAKER_00: Living people have to give their approval.
25:13
SPEAKER_00: So there's been a couple recently that have been named after living people.
25:17
SPEAKER_00: One mineral was actually named after Lindy Elkins Tanton, who's a famous scientist at Arizona State University recently.
25:25
SPEAKER_00: Uh, one of my PhD supervisors had a mineral named after him as well recently.
25:30
SPEAKER_00: But you can't really make compound names.
25:32
SPEAKER_00: So, like for instance, Chris Bullheisite would would probably be frowned upon just because you know you don't want the first and last name in there.
25:40
SPEAKER_00: Sorry.
25:41
SPEAKER_01: Well, okay, but w what about bullheisite?
25:44
SPEAKER_00: Bullheisight would would probably be okay.
25:46
SPEAKER_00: I mean, I think everybody would would it might be frowned upon because nobody knows how to pronounce it.
25:49
SPEAKER_00: It'd be like, you know, bullseasite or something like that.
25:52
SPEAKER_01: But well, that's how that's how we change that though.
25:56
SPEAKER_01: Okay, if we name a mineral after me, then everybody will know it.
25:59
SPEAKER_01: That's true.
26:00
SPEAKER_01: All right, so that's it.
26:01
SPEAKER_00: If anybody out there wants to name a mineral after Chris, he's open to it.
26:04
SPEAKER_00: He will give approval to a mineral being named after him, right?
26:07
SPEAKER_01: Yeah, that's right.
26:08
SPEAKER_01: That's right.
26:09
SPEAKER_00: Um basically you have to get this thing approved by a commission.
26:12
SPEAKER_00: And and uh, you know, you have to think carefully about the name, and and so you can honor living people with it.
26:17
SPEAKER_00: They just have to give their approval.
26:18
SPEAKER_01: Okay, and I do say that like that happens a lot, right?
26:20
SPEAKER_01: Most of the new minerals have been named after people.
26:23
SPEAKER_00: Yeah, many of them, you know, sometimes famous, you know, people who who've passed away, sometimes very well-known scientists who are um who are still alive.
26:30
SPEAKER_00: So yeah, definitely happens.
26:33
SPEAKER_00: Okay, all right.
26:34
SPEAKER_00: So, Chris, the let's just list a couple of these new ones um that have been discovered recently.
26:39
SPEAKER_00: I just I mentioned earlier that uh Lindy Elkins Tenton, who she's a very, like I said, a very famous scientist at Arizona State University, she had a mineral named after her, Elkins Tantinite.
26:49
SPEAKER_00: One of my former um PhD supervisors, Larry Heeman, had hemonite.
26:53
SPEAKER_00: Hold on a second.
26:54
SPEAKER_01: I got a question for you.
26:55
SPEAKER_01: You said no compound names, but that is a compound name.
26:59
SPEAKER_01: Elkins tantinite.
27:00
SPEAKER_00: Elkin's tantinite, she has a hyphenated last name.
27:02
SPEAKER_00: So it's it's Elkin's tantin, is the hyphen.
27:05
SPEAKER_00: Yeah, exactly.
27:06
SPEAKER_00: So her first name is Lindy.
27:07
SPEAKER_00: And it's an extremely it's a I think she's uh extremely well deserving of having a mineral named after.
27:13
SPEAKER_00: So I think they're not gonna be a good thing.
27:13
SPEAKER_00: Yeah, I'm not taking away from that.
27:15
SPEAKER_01: I'm just I'm just questioning the uh yeah.
27:17
SPEAKER_00: So Elkin's tantin is the last name.
27:19
SPEAKER_01: Yes.
27:20
unknown: Okay.
27:20
SPEAKER_00: Um those were both so Elkin's Tantinite was found in a meteorite, um, in one of these old meteorites that had landed decades ago and had been newly investigated.
27:30
SPEAKER_00: And these were actually discovered at the University of Alberta where I uh I did my PhD um by the, very minute quantities, right?
27:39
SPEAKER_00: This this mineral.
27:41
SPEAKER_00: It's it's an interesting thing.
27:42
SPEAKER_00: I think they've been found in the University of Alberta where I got my PhD, has been uh sort of discovering or naming a lot of minerals recently because of two reasons.
27:52
SPEAKER_00: First of all, they're a huge diamond research place, so there's a lot of diamond research that goes on.
27:56
SPEAKER_00: So they name a lot of new minerals found in diamonds.
27:58
SPEAKER_00: But they also have uh one individual who runs the electron microprobe facility there who is a mineral, I say nerd, but nerd in the best way possible.
28:09
SPEAKER_00: Like Andrew Locock, Dr.
28:10
SPEAKER_00: Andrew Locock, loves minerals, loves the details.
28:14
SPEAKER_00: Like he knows the formula for biotite and he knows the formula for every other mica there is out there, probably.
28:19
SPEAKER_00: Like this guy is an incredible repository of just chemical minerals.
28:22
SPEAKER_00: So he's looking on his instrument and sees, oh, this is a new chemistry.
28:26
SPEAKER_00: Maybe it's a new mineral.
28:27
SPEAKER_00: Like he's just you know doing routine analyses and can kind of come across these because he is such a uh has such a detailed knowledge of mineral chemistry.
28:36
SPEAKER_00: So I think that's why really this was discovered there.
28:40
SPEAKER_00: And they have a great meteorite expert who uh was uh you know, sort of collects the meteorites and looks at them as well.
28:45
SPEAKER_00: So this combination of expertise.
28:47
SPEAKER_01: So is the chemical composition determined using mass spectrometry then?
28:52
SPEAKER_00: No, usually it's determined.
28:54
SPEAKER_00: Well, there's a bunch of different techniques for doing that, but uh usually it's what's called electron microprobe analysis, which you blast an electron beam at it, and then the it gives off these characteristic electrical or x-ray signatures.
29:05
SPEAKER_00: In diamonds, when people find stuff in diamonds, you pass X-rays through the diamond, and then those X-rays interact with the mineral inclusion, and you can get both structure and chemistry out of that at times.
29:15
SPEAKER_00: So yeah, okay.
29:17
SPEAKER_00: All right, interesting.
29:18
SPEAKER_00: Okay, and then there's one example of again a mineral we know that exists, it occurs in the same rock that bridgmanite will occur in.
29:27
SPEAKER_00: Um, that is a calcium silica oxygen, so CaSiO3 instead of just MGSIO3, so what is called calcium perovskite.
29:36
SPEAKER_00: And this was proposed to be named Dave Mawite by a suite of researchers, and that again is a compound name, Chris.
29:45
SPEAKER_00: So uh, but that was proposed to be that wasn't lost on me, Jesse.
29:49
SPEAKER_01: I just wasn't gonna I wasn't gonna harp on it.
29:52
SPEAKER_00: We weren't gonna comment on it.
29:53
SPEAKER_00: Um but this was um this has been challenged.
29:56
SPEAKER_00: So uh a a variety of people disagree, think that we know this calcium perovskite mineral exists super deep down in the mantle in the same rock that Bridgemanite exists in, but there are people who say, no, you haven't actually found that.
30:09
SPEAKER_00: That is not a piece of calcium perovskite in that inclusion in a diamond.
30:13
SPEAKER_00: So there's some debate about this type of stuff occasionally.
30:16
SPEAKER_01: All right, Jesse, I want to end then today's episode by asking the question, and and we can each talk to this, but why is this discussion important?
30:27
SPEAKER_01: I mean, this is something that you and I have have had many discussions about in the past in terms of these little funny things that happen in geology, right?
30:35
SPEAKER_01: I mean, we're talking about people that are doing devoting massive parts of their career research to this very topic that we're talking about.
30:43
SPEAKER_01: So why is this an important thing to consider?
30:46
SPEAKER_00: Yeah, it's a great question.
30:47
SPEAKER_00: I'm very curious to hear your answer as well to this, Chris.
30:50
SPEAKER_00: I to me, understanding these weird minerals or finding a natural example of a mineral that we know exists deep down in the earth, like that's an important calibration of our experiments.
31:02
SPEAKER_00: We don't know that it's down there for sure 100% until we find a piece of it.
31:07
SPEAKER_00: We don't know that the middle of the earth is made of bridgemenite until we find a piece of it, really.
31:12
SPEAKER_00: It's sort of confirmation.
31:13
SPEAKER_00: So there's there's value in that.
31:14
SPEAKER_00: I also think that when you've discover these new minerals or find these new chemical structures, there's a lot of material science value in that.
31:22
SPEAKER_00: Like perovskite, the structure that bridgemenite has, is a common um a com well, it's not commonly used in commercial solar panels yet, but it is one of the things that people use in solar panels, is minerals with that structure.
31:37
SPEAKER_00: So we kind of understand how minerals arrange themselves, and sometimes there's actually like real societal use for just understanding the physics and the chemistry of those minerals.
31:45
SPEAKER_00: Uh so that's where I kind of go with it.
31:47
SPEAKER_00: How how about you?
31:48
SPEAKER_00: What what do you um what do you think about this?
31:50
SPEAKER_01: I agree with what you said.
31:51
SPEAKER_01: Um, you know, when we discover new minerals, we're discovering maybe properties that this mineral has that could be important that we haven't thought of yet.
32:00
SPEAKER_01: You know, that's the thing is when university research scientists do this kind of stuff, you just don't ever know really where it's gonna go, what it's gonna lead to, who's gonna take what you learned and use it for something that they're working on that could lead to something super important, you know.
32:17
SPEAKER_01: So I I don't know.
32:19
SPEAKER_01: I guess that's kind of where my mind goes with it too.
32:21
SPEAKER_00: Yeah, I think so.
32:22
SPEAKER_00: I agree completely with that.
32:24
SPEAKER_00: You know, just exploring, sure, we we know how feldspar behaves really well because it's the most common mineral on the surface of the earth.
32:30
SPEAKER_00: And that's super obviously important because it's so prevalent.
32:34
SPEAKER_00: Like it's a hugely important mineral, but it's also valuable to know about the mineral that's like 6,281 that we discover on the surface of the earth, even if it's really rare and only in one random location that we know of, it's important to understand how these things operate because sometimes those little very rare ones can be incredibly important for a lot of different stuff.
32:56
SPEAKER_01: Right.
32:56
SPEAKER_01: And then, you know, if we find something like this that we've never found before, then there's the also the possibility that these things can be created in the lab.
33:04
SPEAKER_00: Exactly.
33:05
SPEAKER_00: I do think sometimes the naming thing gets a bit pedantic, you know, like okay, do we how do you go about naming it?
33:11
SPEAKER_00: What are the rules for mineral?
33:12
SPEAKER_00: Sometimes I I can understand how that would be perhaps a little bit pedantic or or sort of boring or unimportant, some people might think, but I think the the actual science, like the underlying understanding, is super important.
33:25
SPEAKER_00: So and it's kind of cool to name minerals after people who have done a lot for the field of geoscience, um, like Lindy El Constantinite, you know.
33:33
SPEAKER_00: So things like that are kind of cool.
33:35
SPEAKER_00: Chris Bull Highsight, uh, someday we'll have one, perhaps.
33:38
SPEAKER_01: But never gonna happen.
33:41
SPEAKER_01: Never gonna happen.
33:42
SPEAKER_00: Yeah.
33:42
SPEAKER_00: So well, I think that's a wrap, Chris, on this episode.
33:45
SPEAKER_00: You can follow us on all the social medias.
33:47
SPEAKER_00: We're at Planet GeoCast.
33:48
SPEAKER_00: If you want to learn more about minerals and rocks and plate tectonics in a more detailed way with all of the key images, you can go to Camp GR, our conversational textbook.
33:55
SPEAKER_00: That is the first link in the show notes.
33:57
SPEAKER_00: Send us an email.
33:58
SPEAKER_00: A lot of you have you know passed us uh things related to these new minerals recently.
34:03
SPEAKER_00: Um, and so if you have more questions or if you have new questions, please send us an email, planetegeocast at gmail.com.
34:09
SPEAKER_01: Also, go back and look up our episode where we interviewed Gabriela Farfan.
34:13
SPEAKER_00: Oh, yeah, that was a great one.
34:15
SPEAKER_00: That was a great, great, great interview.
34:17
SPEAKER_00: Absolutely great call, Chris.
34:18
SPEAKER_00: Hey, and also leave us a review on your podcast app, a review and a rating.
34:23
SPEAKER_00: Those really go a long way for helping us out with the algorithm.
34:26
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34:29
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34:36
SPEAKER_00: Thanks.