Latest / PlanetGeo: The Geology Podcast / What is a Mineral? Geology 101: Minerals Part 1

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What is a Mineral? Geology 101: Minerals Part 1 · PlanetGeo: The Geology Podcast

0:01
SPEAKER_00: Welcome to Planet Geo, the podcast where we talk about our amazing planet, how it works, why it matters to you.
0:12
SPEAKER_00: Hey folks, it's uh been a while since we've released an episode on the Planet Geo feed, and I promise we have more episodes coming in the works.
0:20
SPEAKER_00: We also have several really exciting projects to announce in the coming months that will help explain our absence.
0:26
SPEAKER_00: But in the meantime, we thought it would be good to release some of our Camp Geo intro to geoscience content right here on the podcast feed.
0:34
SPEAKER_00: A few of the podcast platforms now allow chapter artwork to be displayed in the podcast feed, which is somewhat like what we aim to do in the Camp Geo mobile app.
0:43
SPEAKER_00: So we thought it would be useful to both get your feedback on the product here while also giving you some additional geoscience content you may not have heard yet.
0:51
SPEAKER_00: So this is the intro chapter to Chris and my audio textbook version of the Physical Geology Class textbook, the first class you'd take in a geology major at the college level.
1:01
SPEAKER_00: And you can find more of this content on our custom mobile app, the Camp GeoApp, available in all your app stores, and it's the first link in the show notes.
1:09
SPEAKER_00: We will have lots of new content and some really exciting partnerships coming your way soon.
1:14
SPEAKER_00: But in the meantime, here's Chris and I introducing minerals with images.
1:22
SPEAKER_01: Chris Bullheis.
1:24
SPEAKER_01: Professor Jesse Rymink.
1:25
SPEAKER_01: How are we doing today?
1:26
SPEAKER_01: I like doctor better than professor.
1:28
SPEAKER_00: Professor makes me feel old a little bit.
1:29
SPEAKER_01: Well, that's why I'm going to call you professor.
1:32
SPEAKER_00: I don't do what you like.
1:34
SPEAKER_00: Hey, this is the first episode of this physical geology introduction to geoscience course that we're offering here.
1:40
SPEAKER_00: You're Chris Bullheis.
1:42
SPEAKER_00: I'm Jesse Rymink.
1:43
SPEAKER_00: You're my former high school teacher, a nationally recognized earth science teacher in the great state of Michigan.
1:48
SPEAKER_01: And you are Dr.
1:49
SPEAKER_01: Jesse Rymink.
1:50
SPEAKER_01: You're, like you said, one of my former students, and uh you got your PhD in geoscience and now work as a professor in the geology department at Penn State University.
1:58
SPEAKER_01: That's right.
1:59
SPEAKER_01: And we're gonna begin our class today with our first episode, which is called What is a Mineral and Some Basic Chemistry?
2:09
SPEAKER_00: So, what are we covering today, Chris?
2:11
SPEAKER_00: You know, this is the start.
2:11
SPEAKER_00: I'm really excited about this whole project we got going.
2:14
SPEAKER_00: And this is the start, the first thing out of the gate.
2:16
SPEAKER_00: We're starting with minerals.
2:17
SPEAKER_00: Right, we are.
2:18
SPEAKER_00: Why minerals and what are we gonna cover?
2:20
SPEAKER_01: So we're gonna begin with defining what a mineral is.
2:23
SPEAKER_01: Uh, it's kind of a funny thing in the field of geology.
2:26
SPEAKER_01: We we have a very strict definition of what a what you know, five criteria that something has to be in order to be classified as a mineral.
2:34
SPEAKER_01: If it doesn't meet all five, it's not technically a mineral.
2:38
SPEAKER_01: So we're gonna begin with that, and then we're just gonna get into some really kind of basic chemistry.
2:43
SPEAKER_01: We're gonna talk about the structure of an atom, ionic bonding, covalent bonding, because we have to understand that a little bit before we can kind of understand how atoms stack together to form minerals.
2:55
SPEAKER_00: Yeah, that is exactly right.
2:57
SPEAKER_00: And this is gonna feel a little bit basic if you've had high school chemistry at some point, but it's required to review this stuff because minerals are the building blocks of all rocks.
3:05
SPEAKER_00: Rocks make up our planet, and minerals are a very important connection between how we interact with our planet, really.
3:13
SPEAKER_00: So minerals are sort of the first stage of geoscience, and that's why we're starting with the basics of minerals here.
3:20
SPEAKER_01: Exactly.
3:20
SPEAKER_01: This is gonna seem like a very basic kind of episode, I think, to most people, but I promise you that it is gonna get a little bit more complicated as we progress through.
3:29
SPEAKER_01: And then we're gonna end the episode today with Jesse asking me some questions.
3:33
SPEAKER_01: Um, he's written a couple questions that I have no idea what they are, and we're just gonna kind of that's gonna deal with what the st kind of content that we covered today, and he's gonna see if he can trip me up.
3:44
SPEAKER_01: That's right.
3:44
SPEAKER_01: Won't happen, but he's gonna try.
3:46
SPEAKER_00: Yeah, it's unlikely, but I'm gonna try my darnest.
3:49
SPEAKER_00: All right, shall we begin?
3:50
SPEAKER_00: Let's do it.
3:51
SPEAKER_00: So the first thing we're starting with is the definition of a mineral.
3:54
SPEAKER_00: Again, Chris, you you nailed it.
3:56
SPEAKER_00: We have a very strict classification scheme or strict things that a mineral must have in order to be a mineral.
4:02
SPEAKER_00: And the first one is it has to be solid.
4:04
SPEAKER_00: So minerals are solid, they're not liquids, they're not gases, they are solids.
4:08
SPEAKER_00: They're solid materials.
4:09
SPEAKER_00: So that's number one.
4:10
SPEAKER_00: In that first image of the stack of images you have, we list the definitions, the requirements for the definition of a mineral.
4:16
SPEAKER_00: And the first is solid.
4:17
SPEAKER_01: That's pretty basic, Jesse.
4:18
SPEAKER_01: I think we can move on.
4:19
SPEAKER_01: That's uh pretty straightforward.
4:21
SPEAKER_01: Yeah, number two, in order for something to be classified as a mineral, it has to be naturally occurring, which this just simply means that this has to be it has to be made by a natural earth geoscience process.
4:34
SPEAKER_01: Okay, this can in other words, it can't be made by somebody uh working in a lab wearing a white coat.
4:40
SPEAKER_00: And this part of the definition is kind of changing a little bit.
4:43
SPEAKER_00: This and the next one, inorganic.
4:45
SPEAKER_00: So number three is inorganic, means it's not created by life forms, so it's not created by biology, by animals making things.
4:53
SPEAKER_00: And that definition is kind of changing in the mineralogical community right now.
4:56
SPEAKER_00: We are being more accepting, if you will, of biominerals or things that are created by animals in the process of mineralization.
5:04
SPEAKER_01: Which I I like.
5:05
SPEAKER_01: I think that that makes sense.
5:06
SPEAKER_01: It's still a part of the tight definition for something to be a mineral, but that might go away as we see time move on, and that might just be dropped and it might, you know, move to three criteria or four criteria for something to be a mineral.
5:18
SPEAKER_00: So we have solid, naturally occurring, inorganic.
5:21
SPEAKER_00: Number four is definite chemical composition.
5:23
SPEAKER_00: And this is where, Chris, students kind of get a little bit hung up.
5:27
SPEAKER_00: I mean, I just taught my intro to physical geology class of 220 students, and this is kind of where people start to get hung up.
5:33
SPEAKER_00: The first three are pretty simple.
5:34
SPEAKER_00: Definite chemical composition means that it has to be a discrete and unique chemical composition.
5:41
SPEAKER_00: So this has each mineral has its own set of elements that make up that mineral.
5:46
SPEAKER_01: And they go from the extremely simple to very, very complicated long chemical composition.
5:53
SPEAKER_00: It's so complicated it's hard to memorize.
5:55
SPEAKER_01: Yeah, just some examples of a definite chemical composition.
5:59
SPEAKER_01: You talk about that like the second most common mineral on the planet, or on the crust anyway, which is quartz, has a pretty simple chemical composition.
6:07
SPEAKER_01: It's quartz is SiO2.
6:09
SPEAKER_01: It's silicon and two oxygen atoms that are covalently bonded together.
6:13
SPEAKER_01: And you know, quartz is always good.
6:16
SPEAKER_01: That's the building block of that mineral, are those elements.
6:20
SPEAKER_01: That's the definite chemistry of that mineral.
6:23
SPEAKER_00: That's exactly right.
6:23
SPEAKER_00: Another common one that people think of halite or rock salt is a mineral and it's NaCl.
6:28
SPEAKER_00: It has sodium and chlorine.
6:30
SPEAKER_00: That's it.
6:30
SPEAKER_00: That's what makes up halite, and that's what makes halite unique from other elements that maybe have potassium and chlorine.
6:36
SPEAKER_00: So those would be different minerals.
6:38
SPEAKER_00: So that's our fourth one.
6:39
SPEAKER_00: Chris, what's the fifth piece to a mineral?
6:42
SPEAKER_01: The fifth and last and final part of the definition of a mineral is a definite crystalline structure.
6:47
SPEAKER_01: And what this means is that the way that elements combine when they bond together, they do it the same way every single time.
6:57
SPEAKER_01: It's consistent.
6:58
SPEAKER_01: Okay.
6:59
SPEAKER_01: And so, like for instance, we referred to quartz.
7:03
SPEAKER_01: Quartz is SiO2, and the best way for those elements to stack together is in a hexagonal shape, which means all quartz crystals are going to have six-sided, uh, a six-sided shape to it.
7:15
SPEAKER_01: That's the definite, consistent crystalline structure.
7:19
SPEAKER_00: That's right.
7:20
SPEAKER_00: We'll come back with an analogy about this, but the definite crystal structure is really another one of the keys for a mineral definition to be a specific type of mineral.
7:30
SPEAKER_00: Okay.
7:30
SPEAKER_00: So, Chris, this is something that I think is usually a good question to ask the intro students or students in the introductory uh geoscience class.
7:38
SPEAKER_00: Is a snowflake a mineral?
7:40
SPEAKER_01: Yeah, I asked you this question, young Dr.
7:43
SPEAKER_01: Jesse Rymink sitting in my class, K didn't know anything at the time.
7:48
SPEAKER_01: And yeah, I I asked this all the time.
7:51
SPEAKER_01: And it's so interesting to me because their knee-jerk reaction when I say, Hey, is a snowflake a mineral?
8:00
SPEAKER_01: Their reaction is no.
8:01
SPEAKER_01: My next question of course is gonna be, why not?
8:04
SPEAKER_01: Okay.
8:05
SPEAKER_01: What's your thought process on this?
8:07
SPEAKER_01: And every single time somebody early on in the asking of this question is gonna say, Because there are no two snowflakes that are alike.
8:17
SPEAKER_01: And so I like that answer because it le at least it tells me that they're going through the process, right?
8:24
SPEAKER_01: You have to go through all of the criteria.
8:27
SPEAKER_01: So let's do that.
8:28
SPEAKER_01: Is a snowflake a solid?
8:30
SPEAKER_00: Yes, it is a solid.
8:31
SPEAKER_00: Okay, is it naturally occurring?
8:33
SPEAKER_00: Absolutely.
8:34
SPEAKER_00: Inorganic?
8:34
SPEAKER_00: Yep, totally inorganic.
8:36
SPEAKER_00: Definite chemical composition.
8:38
SPEAKER_00: Yeah, it's just water, H2O.
8:40
SPEAKER_00: That's all that it is.
8:41
SPEAKER_00: So definite chemical composition.
8:43
SPEAKER_01: And then a definite crystalline structure.
8:45
SPEAKER_01: Does it have a definite crystalline structure?
8:48
SPEAKER_00: Yeah, I mean it's ice, it has the bonding environment.
8:50
SPEAKER_00: Water is bonded in such a way as it's ice, and so yes, it has a definite crystal structure.
8:55
SPEAKER_01: Every snowflake, they're beautiful.
8:57
SPEAKER_01: Snowflakes are beautiful little crystals, right?
8:59
SPEAKER_01: And they have six points on, they have six sides to it.
9:02
SPEAKER_01: So, where does this statement come from?
9:04
SPEAKER_01: Like, I I can see Linda Rymink saying to young Jesse, Jesse, look at the beauty of these snowflakes.
9:12
SPEAKER_01: And Jesse, you're sitting at a window and you're watching these big fluffy flakes fall down.
9:16
SPEAKER_01: And then Linda reaches reaches over, puts her arm around you, and says, Jesse, there are no two snowflakes that are alike.
9:24
SPEAKER_01: And guess what, Jesse?
9:25
SPEAKER_01: You're a snowflake too.
9:28
SPEAKER_00: I am a pretty little snowflake.
9:30
SPEAKER_00: You are.
9:31
SPEAKER_00: Yeah, so the the although the form that they take can be somewhat different, the internal structure is always the same.
9:39
SPEAKER_00: So although the kind of shape of any individual snowflake can be a little bit different, much like a mineral, many minerals will have slightly different shapes.
9:47
SPEAKER_00: You know, they'll be more or less rugged, different sizes, but internally they have the same structure.
9:52
SPEAKER_00: And so therefore, they qualify with all of those five things to be a mineral.
9:57
SPEAKER_00: So a snowflake is a mineral.
9:59
SPEAKER_01: That was a rambly answer, Jesse.
10:03
SPEAKER_01: You rambled, okay?
10:04
SPEAKER_01: You call me a rambly old man, but man.
10:06
SPEAKER_01: Um, all right.
10:07
SPEAKER_01: Hey, can we move on?
10:09
SPEAKER_00: Yeah, let's talk about how these elements bond together to make minerals, to make this definite crystal structure.
10:16
SPEAKER_00: And there are really there's several ways elements can bond with one another.
10:20
SPEAKER_00: There's two key important ones here, but before we get to that, we need to recover the basic structure of an atom.
10:26
SPEAKER_00: Each discrete atom is an element, and those are the building blocks for minerals.
10:30
SPEAKER_00: So let's get into that, Chris.
10:32
SPEAKER_01: And this is the second image that's available for you, just this basic structure of an atom.
10:38
SPEAKER_01: And when you look at that image, you're gonna see that the basic structure of an atom is there are three subatomic particles.
10:44
SPEAKER_01: You have protons, neutrons, and electrons.
10:47
SPEAKER_01: Okay.
10:48
SPEAKER_01: And the atom has two basic parts.
10:52
SPEAKER_01: It has a nucleus, and then it has this kind of what we often refer to as the electron cloud.
10:57
SPEAKER_01: Okay.
10:58
SPEAKER_01: And so in the nucleus, this is where you have the protons and neutrons.
11:03
SPEAKER_01: So, Jesse, run down real quick what a proton and a neutron are.
11:08
SPEAKER_00: Yeah, we'll go through this pretty quick because this is review, but a proton is a heavy building block of an atom that has a positive charge, has a plus one charge.
11:17
SPEAKER_00: A neutron is also heavy, it has one atomic mass unit, it weighs one, and it is neutral, so it has no charge to it.
11:23
SPEAKER_00: So both of those are in the nucleus, so the nucleus overall has a positive charge.
11:27
SPEAKER_00: And then Chris, what's what's in the electron cloud?
11:31
SPEAKER_01: Well, real quick, one thing I want to add to the whole thing about nucleus, though, is the nucleus of an atom is incredibly tiny.
11:38
SPEAKER_01: Okay, you can think about this if like if you imagine a classroom.
11:42
SPEAKER_01: I talk about this with my kids, they're sitting in a classroom.
11:44
SPEAKER_01: I got 30 kids in my geology class, right?
11:46
SPEAKER_01: And say, all right, well, let's magnify an atom to the size of this room.
11:50
SPEAKER_01: Let's blow this thing up, right?
11:52
SPEAKER_01: Well, if you take that kind of thing, a typical 30, you know, seat classroom, and you think, all right, well, this is the structure of an atom.
12:00
SPEAKER_01: If I dangle a sharpened pencil from the ceiling, the tip of that pencil is the size of the nucleus of an atom.
12:09
SPEAKER_01: So that means the rest of my room where all of my students are and where I'm standing up in front of them talking, the rest of that is just electron cloud.
12:17
SPEAKER_01: Okay.
12:17
SPEAKER_01: And in that very tiny tip of the pencil analogy, that's where all of the mass of the atom is.
12:24
SPEAKER_01: Electrons have virtually no mass.
12:26
SPEAKER_01: They have a very small mass, and we can talk about that here when we talk about electrons, but you're never going to count the mass of electrons.
12:34
SPEAKER_00: But they do have charge, and they have a negative charge, which offsets the positive charge of the proton that is sitting in that very tiny pencil tip hanging in the middle of your classroom.
12:46
SPEAKER_00: And so, in a neutral atom, an atom that has no overall charge to it, there are the same number of electrons in the electron cloud as there are protons in the nucleus.
12:57
SPEAKER_00: And that would make a neutral atom.
12:59
SPEAKER_00: That neutral atom won't really bond to anything, though, because charge is what drives most bonding environments.
13:07
SPEAKER_00: And so because the nucleus is so tiny and it's so dense, it's held together really tightly.
13:14
SPEAKER_00: The electron cloud, with all this space, all the stuff that's filling up the rest of your classroom with where students are sitting, there's a lot of space there.
13:22
SPEAKER_00: Any given electron is not held super tightly.
13:24
SPEAKER_00: So these electrons can move around between atoms, and they are really what drives bonding between different atoms.
13:31
SPEAKER_01: So that's a perfect segue to get into the two broad kinds of chemical bonds are ionic bonds and covalent bonds.
13:37
SPEAKER_01: So let's talk about these.
13:39
SPEAKER_01: You that we have an image, the third image in your stack shows an image of how ionic bonding happens.
13:46
SPEAKER_01: And you know, I when I talk about this with my students too, they don't struggle with this.
13:51
SPEAKER_01: This is pretty basic stuff.
13:53
SPEAKER_01: You know, basically, ionic bonding involves the transfer of electrons.
13:58
SPEAKER_01: Atoms will gain electrons and some atoms will lose electrons.
14:01
SPEAKER_01: And what drives this, like gaining or losing electrons, is trying to achieve stability.
14:08
SPEAKER_01: Atoms are most stable when they have a full outer shell of electrons.
14:14
SPEAKER_01: That's we often call that a valence shell.
14:16
SPEAKER_01: Okay.
14:17
SPEAKER_01: And so if it has, like, you know, if the valence shell can hold eight electrons, but it only has seven, the atom only has seven.
14:24
SPEAKER_01: It's really easy for that atom then to pick up an electron, and now all of a sudden the valence shell goes from seven to eight, and bam, it's stable right there.
14:34
SPEAKER_00: And so that is like the chlorine atom in the bottom of that third image.
14:38
SPEAKER_00: It needs one more electron to make a full shell.
14:41
SPEAKER_00: So it takes one, and sodium has an extra electron.
14:44
SPEAKER_00: It has a shell that has maybe only one electron when it would be full if it had eight, but it only has one.
14:50
SPEAKER_00: So it's easier for it to lose that electron to get back to a full outer shell than to gain seven.
14:56
SPEAKER_00: So it'll lose one, it'll give it to chlorine.
14:58
SPEAKER_00: Now we have these two atoms, sodium, it's lost an electron, so overall it has a positive charge.
15:03
SPEAKER_00: Chlorine has gained an electron, overall it has a negative charge.
15:07
SPEAKER_00: Those two things will be attracted to one another and they'll form an ionic bond because of this transfer of this outer valence shell electron between the two atoms.
15:15
SPEAKER_01: Comes back to the electrical nature of matter.
15:18
SPEAKER_01: Opposites attract.
15:19
SPEAKER_01: Okay.
15:20
SPEAKER_01: And so ionic bonding is just that.
15:22
SPEAKER_01: It is if an atom loses an electron, it becomes positively charged ion, and we call that actually a cation.
15:29
SPEAKER_01: Okay.
15:30
SPEAKER_01: And I I I do this with my class too, and I it it's cringy when I do this, but I'll say cation is like, you know, you think of it as it's positive or it's positive, like a oh, that is that is bad, Chris.
15:45
SPEAKER_01: That's so bad in that.
15:46
SPEAKER_01: That's so bad.
15:48
SPEAKER_00: Does it work though?
15:49
SPEAKER_00: I mean, you've perfected this over 25 years, so it must work if you're using something that bad.
15:52
SPEAKER_00: Yeah, it does work.
15:53
SPEAKER_00: It does work.
15:54
SPEAKER_01: Yeah.
15:54
SPEAKER_01: So cations are positively charged ions, and then the negatively charged ions, the an atom that has gained an electron, that's called an anion.
16:02
SPEAKER_01: And I don't have a corny analogy for that.
16:04
SPEAKER_01: But as long as you know what a cation is, positive, then you know what an anion is.
16:09
SPEAKER_00: Yeah, then you know anion.
16:10
SPEAKER_00: So a cation gives up the electron, anion takes the electron, and then they bond together.
16:14
SPEAKER_00: So that is ionic bonding.
16:17
SPEAKER_00: Now we're going to shift to covalent bonding, which is in some ways similar, except it's not a transfer of an electron.
16:24
SPEAKER_00: This is sharing of an electron.
16:25
SPEAKER_00: And it has the same principle.
16:27
SPEAKER_00: Both atoms want to have a full valence shell of electrons, but in covalent bonds, they share electrons between the two of them.
16:35
SPEAKER_00: So the fourth image in that stack shows several different types of covalent bonds in common molecules.
16:41
SPEAKER_00: So hydrogen, H2, oxygen, O2, that's molecular oxygen.
16:46
SPEAKER_00: So there's two oxygen atoms together, is a covalent bond.
16:50
SPEAKER_00: They are sharing four electrons there, those two atoms together to make a diatomic molecule of oxygen.
16:57
SPEAKER_01: The bottom line with that is ionic bond involves the transfer of electrons that forms ions, and then oppositely charged ions are attracted to each other.
17:05
SPEAKER_01: Covalent bonds, they achieve a full valence outer shell of electrons too, but they do it instead by sharing electrons with nearby atoms.
17:13
SPEAKER_00: It's a much nicer way to make a bond.
17:16
SPEAKER_00: You know, you're not stealing electrons, you're sharing electrons.
17:18
SPEAKER_00: This is like you probably teach your kids they should be sh covalently bonding, not ionically bonding with one another.
17:25
SPEAKER_01: Okay.
17:25
SPEAKER_00: That was that bad.
17:26
SPEAKER_00: That was too bad for you, Chris.
17:28
SPEAKER_01: Yeah, that was, yeah.
17:29
SPEAKER_01: I I like I think that was worse than my positive analogy, but you know, anyway.
17:33
SPEAKER_01: It might be, but it also worked.
17:34
SPEAKER_00: All right, Jesse, let's wrap this up.
17:36
SPEAKER_00: Let's wrap it up with a with an analogy here, Chris, right?
17:38
SPEAKER_00: We got a decent analogy for bonding.
17:40
SPEAKER_01: Well, yeah.
17:40
SPEAKER_01: The reason why we did this chemistry in the way that atoms will kind of combine with other atoms, that's how minerals grow.
17:47
SPEAKER_01: They they grow then this way that atoms and molecules are going to be stacking together to form this definite crystalline shape.
17:55
SPEAKER_01: So here's the analogy that I like to give to my students.
17:59
SPEAKER_01: I say, okay, well, Jesse, if I were to come into the classroom and with a bucket, a five-gallon bucket full of just tennis balls, right?
18:08
SPEAKER_01: Nothing else in the bucket, just tennis balls, and say, okay, Jess, your job is take these tennis balls.
18:15
SPEAKER_01: You can't use anything except the floor, and I need you to make a stack of tennis balls on the floor.
18:20
SPEAKER_01: Okay.
18:21
SPEAKER_01: And what are you going to do?
18:23
SPEAKER_00: Well, I'm probably going to put a one layer of tennis balls in a grid on the floor, first of all.
18:28
SPEAKER_00: And then I'm going to take the second layer of tennis balls and I'm going to put those in the little gaps between them.
18:34
SPEAKER_00: I'm going to make little pyramids of tennis balls, right?
18:36
SPEAKER_00: And that'll create another layer.
18:37
SPEAKER_00: And then I can probably put them on a third layer of tennis balls by putting another third layer in the gaps I made on the second layer.
18:45
SPEAKER_00: So you kind of stack these in the gaps, not right on top of each other, not a tennis ball right on top of another tennis ball, but a tennis ball on top of four tennis balls sitting together, right?
18:55
SPEAKER_00: That would be the most efficient way to stack tennis balls.
18:58
SPEAKER_00: Did I get that right?
18:59
SPEAKER_00: Is that is that right?
19:00
SPEAKER_01: Absolutely.
19:01
SPEAKER_01: You're going to make a stack that's the most stable way to stack it together.
19:05
SPEAKER_01: And as long as you're dealing with just tennis balls, so you know, the consistent chemistry, right, that we talked about before, as long as you're dealing with that, then the best way to stack that together is a pyramid.
19:15
SPEAKER_00: And that would be our definite crystalline structure, the way to stack those tennis balls.
19:20
SPEAKER_01: But if I came in the next time, okay, I come in with a bucket full of tennis balls and much, much smaller marbles.
19:28
SPEAKER_01: Okay.
19:29
SPEAKER_01: And I say it's the same thing, right?
19:31
SPEAKER_01: Take this, the contents of this bucket, and let's say it's roughly half and half.
19:34
SPEAKER_01: I got half of the bucket is full of marbles, and half of the bucket is full of tennis balls.
19:39
SPEAKER_01: I have roughly the same amount.
19:40
SPEAKER_01: Um make a stack.
19:43
SPEAKER_01: Now, my chemistry is different, right?
19:45
SPEAKER_01: My chemical composition has changed.
19:47
SPEAKER_01: The size and the well, the shape hasn't changed, but the size of what I'm dealing with has changed.
19:51
SPEAKER_01: So what are you going to do now?
19:53
SPEAKER_00: Well, I'm probably going to have to fit all those marbles in the gaps between the tennis balls.
19:57
SPEAKER_00: So I'm going to put the marbles in the little gaps between the tennis balls and fit those into the stack in the most efficient way possible.
20:05
SPEAKER_00: So in between four tennis balls in any one layer, I'll have a marble sitting in there.
20:09
SPEAKER_00: And that'll change how I stack the second layer of tennis balls, probably as well.
20:13
SPEAKER_00: The tennis balls might need to go right on top of all the other tennis balls.
20:17
SPEAKER_00: So I would have a vertical array of tennis balls and marbles in between.
20:21
SPEAKER_01: Exactly.
20:22
SPEAKER_01: So you're going to end up then with more of a cubic shape.
20:26
SPEAKER_01: Right away, you're probably thinking, yeah, but the tennis balls that are on the edge are going to fall off.
20:31
SPEAKER_01: And this is where the analogy kind of falls short a little bit.
20:34
SPEAKER_01: Because in reality, those tennis balls on the edge are not going to fall off because they're held in place by ionic or covalent bonds.
20:41
SPEAKER_01: It's kind of like the glue holding the structure together.
20:45
SPEAKER_01: Okay.
20:46
SPEAKER_01: But the analogy still works because I'm using different materials now.
20:51
SPEAKER_01: There's a different way to stack them together in a more stable form.
20:56
SPEAKER_00: And so that is our definite chemical composition, the tennis balls or the tennis balls plus marbles.
21:03
SPEAKER_00: And those discrete chemical compositions will have definite crystal structures, the ways to stack them together.
21:10
SPEAKER_00: So that's kind of the analogy to make a mineral here.
21:13
SPEAKER_00: And this is how elements make up minerals and minerals make up rocks.
21:18
SPEAKER_00: So that's kind of the hierarchy of materials here in geosciences.
21:22
SPEAKER_01: Right on.
21:23
SPEAKER_01: So to bring this around like full circle, this is the way I always say it to my own students, and you do as well to your students, is that because there is a consistent chemical composition, there is a definite crystalline structure.
21:36
SPEAKER_00: Perfect.
21:37
SPEAKER_00: I love that.
21:37
SPEAKER_00: That's great.
21:38
SPEAKER_00: Yep.
21:38
SPEAKER_00: That's great.
21:39
SPEAKER_01: So, Jesse, that kind of is going to conclude the lesson for today.
21:43
SPEAKER_01: So, again, what we covered today is the criteria for something to be a mineral.
21:47
SPEAKER_01: We went into some basic chemistry, talked about the structure of an atom.
21:51
SPEAKER_01: We talked about protons, neutrons, and electrons.
21:54
SPEAKER_01: We talked about the two common forms of bonds, ionic bonds and covalent bonds.
21:59
SPEAKER_01: And then we just kind of ended with this analogy of definite chemical composition drives a definite crystalline structure.
22:06
SPEAKER_00: That's right.
22:07
SPEAKER_00: This is a good building block.
22:08
SPEAKER_00: We're building off of this in the coming lectures.
22:10
SPEAKER_00: But before we get to that, Chris, I got a couple questions to kind of quiz you on here.
22:14
SPEAKER_00: You ready for it?
22:14
SPEAKER_00: Let's do it.
22:15
SPEAKER_00: All right.
22:15
SPEAKER_00: Yep.
22:15
SPEAKER_00: All right.
22:16
SPEAKER_00: Question number one.
22:17
SPEAKER_00: Why are mineral compositions almost always constant?
22:21
SPEAKER_00: So why do they have a definite chemical composition?
22:24
SPEAKER_00: And the answers, potential answers here, are A, there's one best way to fit a particular combination of elements into their structurally sound order.
22:34
SPEAKER_00: B, there's only a certain amount of each element on the surface of the earth.
22:38
SPEAKER_00: Or C, there are only a few combinations of minerals that occur on Earth's surface.
22:45
SPEAKER_00: A, B, or C.
22:46
SPEAKER_00: A, there's only one best way to fit a particular combination of elements together.
22:50
SPEAKER_00: B, there's only a certain amount of each element on the surface of the earth.
22:53
SPEAKER_00: Or C there are only a few combinations of minerals on Earth's surface.
22:57
SPEAKER_01: Yeah.
22:57
SPEAKER_01: I mean, okay, that's that's pretty it's harder because I'm listening to it, but it's definitely A.
23:02
SPEAKER_01: Okay.
23:02
SPEAKER_01: It comes back to the very last thing that I said.
23:05
SPEAKER_01: There's one best way to stack them together.
23:07
SPEAKER_00: Yes.
23:07
SPEAKER_00: That was kind of an easy one.
23:09
SPEAKER_00: C is interesting because there's there's actually not only a few combinations of minerals that occur on Earth's surface.
23:14
SPEAKER_00: There are many thousands.
23:15
SPEAKER_00: There are several thousand minerals that occur on Earth's surface, which we'll get into a little bit more later.
23:21
SPEAKER_00: Question number two, another easy one, Chris.
23:23
SPEAKER_00: This should be a give me.
23:24
SPEAKER_00: We're starting out easy here.
23:26
SPEAKER_00: What is the correct order?
23:27
SPEAKER_00: A minerals, rocks, elements, B, rocks, minerals, elements, or C, minerals, elements, rocks.
23:36
SPEAKER_00: That was A.
23:37
SPEAKER_00: Minerals, rocks, elements, B, rocks, minerals, elements, C, minerals, elements, rocks.
23:46
SPEAKER_01: No, it should be a D.
23:48
SPEAKER_01: You're this is not this is not a this is a horrible question.
23:52
SPEAKER_01: It should be D, elements, minerals, rocks.
23:56
SPEAKER_00: Yes, but B is that in reverse order.
23:59
SPEAKER_00: Come on, Chris.
24:00
SPEAKER_00: Keep up.
24:00
SPEAKER_00: Try try and keep up here.
24:02
SPEAKER_00: Rocks, if you want to go in large to small, we go rocks.
24:06
SPEAKER_00: Oh, that's what we're doing.
24:08
SPEAKER_00: Well, rocks are made of minerals.
24:10
SPEAKER_00: Minerals are made of elements.
24:11
SPEAKER_00: So B is also correct.
24:12
SPEAKER_01: Oh, I always work.
24:14
SPEAKER_01: No, no, no, no.
24:15
SPEAKER_01: I totally disagree with you.
24:16
SPEAKER_01: I always work small to big.
24:18
SPEAKER_01: Always.
24:18
SPEAKER_00: Well, then you would get this wrong.
24:20
SPEAKER_01: Rocks, minerals, elements would be the right one.
24:22
SPEAKER_01: Oh, well, that's a horrible question.
24:24
SPEAKER_01: I'm gonna be one of those students that's gonna come to you and say, uh, Professor Rymank, um, I really didn't like this question, and they're gonna chew you up.
24:32
SPEAKER_00: Bring it on, Chris.
24:33
SPEAKER_00: We'll see how you do next episode here.
24:35
SPEAKER_00: Okay, I'm one out of two.
24:38
SPEAKER_00: All right, that's a wrap on this one.
24:39
SPEAKER_00: Check out those images and uh tune in to the next episode to move on in our lessons here.
24:44
SPEAKER_00: See you next time.
24:45
SPEAKER_00: See ya.