33. Tourmaline Part One: Conquistadors and the party where everyone's invited

Join us as we explore the fascinating world of tourmaline, its formation, varieties, and historical significance, with insights from gemmologists Lucinda and Simon.

Tourmaline's chemical complexity and isomorphous series
Formation of tourmaline in pegmatites and metamorphic rocks
Varieties of tourmaline and their unique features
Historical lore and the myth of pyroelectricity
Testing and identifying tourmaline in gemmology

Simon and Lucinda

Titles
The Hidden World of Tourmaline: From Conquistadors to Colourful Crystals
Unlocking the Secrets of Tourmaline: Varieties, Formation, and Lore

 sound bites
"Paraiba tourmalines glow like neon blue."
"Rubellite is the most popular tourmaline."
"Rubellite is a deep, moody red."

Chapters
00:00 Introduction to Facet nation and Personal Updates
04:26 Shout Outs and Community Engagement
08:38 Exploring Tourmaline: A Gemstone Overview
12:59 The Chemistry and Characteristics of Tourmaline
17:28 Historical Significance and Unique Properties of Tourmaline
20:26 The Science Behind Tourmaline
24:17 Formation of Tourmaline
29:24 Varieties of Tourmaline
36:40 Favourite Tourmalines and Their Unique Qualities

Instagram - https://instagram.com/facetnationgemmology

tourmaline, gemstones, gemmology, mineral formation, jewellery, gem varieties, gemstone history, gem testing, gem inclusions

Transcript

SPEAKER_02 0:06

Hello and welcome to Fascination, a gemology podcast. My name is Simon.

SPEAKER_00 0:11

And I'm Lucinda.

SPEAKER_02 0:13

Today we are coming at you with an episode about tourmaline. But before we get into that, Lucinda, how are you doing?

SPEAKER_00 0:21

I'm doing very well, thank you. I was just telling you about my new TikTok obsession, which is Chinese dancing live streamers. How are you?

SPEAKER_02 0:27

Yeah, I'm okay. It's Sunday, the twenty sixth of April, today, and yesterday I went to watch my favourite football team, which is Southampton, play at Wembley in the FA Cup semi-final against Manchester City, who are, if anybody doesn't know, like people from other countries and things, because if you are from England, you'll probably will know. Probably the best football team in the world, if not one of the best, one of the top three. And Southampton are in the division below Manchester City.

SPEAKER_00 0:56

So you're not even in the same league.

SPEAKER_02 0:59

Not even in the same league, no. And we had we've already beaten Arsenal, who are like the second best team in the country, arguably the best, but you know, that's up for debate because they're level on points in the in the league at the minute. We already beat them in the previous round. And then we got a trip to Wembley today, which is obviously very exciting for football fans of my persuasion who support the lesser teams. And it goes back to what we said in the last episode about the energy and the transfer of energy. Like Southampton had absolutely no right to do well in this game. And we took the lead in the 80th minute, so with 10 minutes to go, and obviously we all went absolutely bananas. And uh for three minutes until they equalized, we thought we we thought three minutes ever. And then five minutes after that, they scored a winner from like 30-35 yards. It was a like an amaz amazing goal, and sort of showed their quality. But the point is, I feel like our team, who individually are not as talented, not as expensive, not as good of players as the Manchester City runs, took a lot of energy from us fans. Man Manchester City are in our Wembley like three or four times a year. This is like an everyday occurrence for them. And like we don't get to go very often, so we have more fans there, we've made more noise, and the team took on the energy and uh did us proud. So I had a really good day. I'm a little bit hungover today, but uh yeah, it's all good. Also, it's the under marathon today, which is something else we mentioned. So what's going on?

SPEAKER_00 2:28

It's all coming together.

SPEAKER_02 2:29

Yeah, it is, everything's quite topical. Before we start today, I've got a couple of shout-outs. This week we had a message from someone by the name of Abigail, and she had some very nice things to say about the podcast, and she is, I hope I'm allowed to say this, she said that that podcast has been really useful for her research because she is writing a book. And it's a book that involves gemstones and it's like a fantasy novel, as far as I'm aware. And she's sort of working on the first draft of it now, and I think she's going to let us have a read and see what we think. So that sounds really exciting and uh really cool. She's also studying with a GIA, and she says um the podcast has been really helpful. So Erbigail, thank you so much for um sending us a message. And then secondly, I also said there's someone that I work with called Jurgen, who um I told him I'd give him a shout out, and he uh has recently started going to sort of antique centres and random places around the country and buying random rings with random stones in them, and coming to me to be like, Simon, I need you to test this for me because I think I'm gonna be a millionaire. Inevitably they tend to not be worth lots of money. He's like the sort of work colleague version of my mum.

SPEAKER_00 3:45

I was gonna say, this is a service you've offered before.

SPEAKER_02 3:48

Um he refers to me as Mr. Nation and keeps phoning me all the time and he's like, uh, I've just seen this stone, what do you think it is? And I'm like, Jurgen, I don't know, that's a picture. You're gonna have to you're gonna I think I have to buy it and take the punt and bring it to me. He's had a couple of successes, like he bought a um he bought a topaz quite cheap and then managed to set it on for um a decent profit. Nice. And um he's had some chrome diopsi, he's had some tourmaline, he bought on massive citrine the other day. I told him not to do that, but he did it anyway. Yeah, but it's been quite fun for him to sort of bring these things to me and be like, uh, this was this, what's this? Is it worth raising money? So uh Jugin, that's been a source of enjoyment for me. So thanks to you.

SPEAKER_00 4:26

And also, guys, thank you to everybody who's participating in our social media polls. This is something that I tend to do on my commute home to amuse myself, and it's very fun. So everybody head to our social media, check out if we have anything on the stories. And every Friday we're starting to share beautiful things that we're obsessed with. So if you see anything, any stones that you love, send them to us and they can make our Friday Roundup.

SPEAKER_02 4:46

Friday Roundup. Nice.

SPEAKER_00 4:47

We're here to have fun, Simon. Come on.

SPEAKER_02 4:49

Yeah, absolutely. So tell us what's happening today.

SPEAKER_00 4:52

Yeah, so today we are going to talk about a very famous Californian. Obviously, I am a very famous Californian, but I am not the only one. The other one is, of course, tourmaline. Tourmaline is an amazing stone. I love it. It's one of my favorites by far. I actually didn't know it existed until I started my foundation degree, but it really is my perfect stone because it's super cost effective. I'm an American, two carat minimum. You can get really big stones very affordably, and it performs extremely well. It's got beautiful color, it's sparkly, but it's not gauche. And this week we're gonna talk all about it. It's actually quite a complex stone, Simon. What's your take on tourmaline?

SPEAKER_02 5:29

Well, so obviously, I don't know, but not maybe not obviously, but tourmaline is the dad of one of the most valuable and prized gemstones on earth. Like super, super. Now we're not gonna specifically speak about that particular version of Tourmaline today. Apparently, Lucinda, that's coming in another episode.

SPEAKER_00 5:46

Yes, we're going to touch on it, and then we'll have a part two where we're gonna deep dive into the specific members of this family.

SPEAKER_02 5:54

Okay. For today, we are going to be treated to um one of Lucinda's story times. Oh, Lucinda's story times tend to involve conquistadors, and this is um this is the case again today. But interestingly, this week um it's also going to involve a famous family of Swedish actors. Let's see how we can uh let's see how we can roll that into one.

SPEAKER_00 6:18

I may have had a glass of rose while I was writing these episodes. Okay, fair enough. All right, everybody close your eyes. We're going back in time, as always, with these jumps. Okay, so once upon a time, Simon and I were recording a podcast, and we were telling you guys about conquistadors and how they were obsessed with finding emeralds in South America. And as they were doing this, they ignored all of the beautiful jadite that's been there. So deposits in the Montegua Valley in Guatemala, all of this stuff that they were finding as they were destroying these civilizations. So these knives and jewelry and axes and tools and icons carved out of beautiful jadite. What can we even say about these guys? So the conquistadors who invaded and eventually conquered these civilizations, like the Olmec and the Maya, had their minds on emerald. They were so hyper-focused on that, right? Greenstone. To the Spanish, Jadite was completely unknown. It wasn't important, but they knew emeralds and they knew that emeralds signified wealth and status and it had value in their society. So the year, sometime in the fifths, let's not get too specific. Let's not get bogged down in specific. In details.

SPEAKER_02 7:25

We don't need the finer details, don't worry. Sometime in that hundred year period.

SPEAKER_00 7:30

Legend has it that an unnamed conquistador stumbled across a green stone. He thought he was going to be rich. He thought he had an emerald. But what he'd actually done is he'd thrown this well-ordered world in which emerald was the green stone and emerald had the value into chaos because he had introduced a new green stone into the game, a third party who could cosplay essentially as any stone. And if the tales are to be believed, this was the first time anyone had ever, well, it wasn't the first time people knew about this stone. They couldn't identify it. But this was where we think tourmaline entered the Western imagination. It would be 300 years until we could prove it, but this is where some people say tourmaline first came to our attention. Simon, what is tourmaline?

SPEAKER_02 8:20

Um, so one of those stones that can, like you said, be good at imitating other stones. So it has a variety of colours, and you can sort of substitute it in for a lot of like the major platters, like your rubies, your emeralds, as you just said, and uh even your sapphires.

SPEAKER_00 8:38

Yes. And chemically, it is a complex borosilicate of aluminum, magnesium, and iron. Do you guys say aluminium?

SPEAKER_02 8:45

We say aluminium, yes.

SPEAKER_00 8:47

I say aluminum.

SPEAKER_01 8:49

That's fine.

SPEAKER_00 8:50

So that's what you need to say when Jemai uh Yeah.

SPEAKER_02 8:55

So basically, if you were going to test a tourmaline gemstone with an XRF, for example, you would find that it is very complex, has like a massive chemical composition list, like extensive atomic substitutions, and like a huge list of major, minor trace elements, much more so than most of your gem materials. It's kind of like chemical chaos. I have likened it to a slightly more inclusive Metcala of the gem world. So if you're not invited to the tourmaline party, then you must have done something very, very wrong because it takes all comers. I feel the Metcala is a bit more exclusive than that, but I'll take the more inclusive version of the Metcala. It's like the one that anyone can come to.

SPEAKER_00 9:39

Well, and it's also full of celebrities. If you think of tourmaline, you can think of tourmaline almost as like the cast of your favorite soap opera. It is messy and it's built around two co-stars. So those are silicon and boron. These are the essential backbone of the crystal structure. They're always going to be there. But they're joined by a rotating cast of metals. These are our guest stars. Magnesium, aluminum, iron, lithium, copper, manganese, loads of stuff is popping up because tromaline is an isomorphous series. Simon, tell me more about those.

SPEAKER_02 10:09

So yeah, an isomorphous gem material is a material which has contained alternative atoms and elements and minerals within the same crystal structure. So basically the structure stays the same, but the elements can swap in and out and like get all, you know, there's no sort of like defined chemical composition they can sort of swap around and substitute in for one another. Very similar to garnets in that sense.

SPEAKER_00 10:34

Exactly. And as Simon has insinuated, you can think of tourmaline as an acting family. So you can think of them as like the Skarsgards, for example. You have Stellen Skarsgard, somber, older Swedish man, yes.

SPEAKER_01 10:49

Okay.

SPEAKER_00 10:49

You have Alexander Skarsgard, very tall, handsome, sexy man.

SPEAKER_01 10:54

Right.

SPEAKER_00 10:55

You have Bill Skarsgard, kind of strange rating that's very talented. Yes, that's the one. Right. You have Peter Sarsgard, who is not a Skarsgard, but is a blonde male actor.

SPEAKER_02 11:07

Okay. I don't know who that is.

SPEAKER_00 11:09

He's um I always think of him as my dad because he was in a movie called Shattered Glass, where he plays a journalist in the 90s, and he looks exactly like my dad when my dad was at law school.

SPEAKER_01 11:17

Okay.

SPEAKER_00 11:18

So that's just a little bit of Lucinda lore for you guys.

SPEAKER_01 11:20

Yep, no, fair enough.

SPEAKER_00 11:23

What we're basically saying is all of these men are alike, but they're also different. They have their own kind of je ne sais quoi whilst also being clearly related and part of the same family. That is Tourmaline.

SPEAKER_01 11:35

Got it.

SPEAKER_00 11:36

Also, like the Scars Guards. Tourmaline is one of the hot girls. She's trigonal.

SPEAKER_02 11:40

Yes, and actually very easily identifiable.

SPEAKER_00 11:43

Yeah. I was like praying. I was praying that our crystal would be tourmaline when we were doing our foundation exam. And it was. We got so lucky.

SPEAKER_02 11:52

It kind of looks like a pencil, I suppose, for want of any other description. It's very long, it's very thin, prismatic, it's a long, thin prism, um, often in a sort of triangular shape, so three sides, trigonal, and they're often sort of convex. So they're sort of a rounded triangle. If you looked through, if you looked down the C-axis, which is down the length of the crystal, you'd see sort of like a rounded, a rounded triangle. Um they can also be six-sided, so hexagonal. And you can also have combination forms which produce sort of like nine and twelve-sided crystals, but the majority are going to be like these three, these three-sided sort of chubby, chubby triangles.

SPEAKER_00 12:33

So cute. And they often have so you can describe them as long, so or tall, heavily striated often. Parallel growth is common, and zoning will often follow trigonal symmetry, which essentially means if you okay, so think about a watermelon. We're going to talk about watermelon tourmaline in a bit because it is actually often misunderstood. What it's meant to be, it's not half pink and half green like you may have seen. It's actually green. Exactly. True watermelon tourmaline is green on the outside and pink on the inside. So sort of like the flesh and the skin. So that is an example of zoning following trigonal symmetry, essentially.

SPEAKER_01 13:13

Very nice.

SPEAKER_00 13:14

What else can we say about trigonal or about uh tourmaline crystals, Simon?

SPEAKER_02 13:17

So tourmaline crystals have pyramidal terminations at either end. So they're gonna sort of converge to a point, unless, of course, they are broken. So often you'll find that the crystals break off their host rock and um they're gonna literally be sort of fractured off. There's no sort of cleavage coming across here because the cleavage is uh very difficult and quite indistinct. So you're not gonna see these sort of like you know, like your your like your cleaving materials, like your fluorides and things with your terrace like markings, they're just gonna have sort of broken off. So that's gonna that's gonna stop you from being able to see the pyramidal terminations as it were. Their stability is very good and their toughness is good, and they have a hardness of like seven to seven point five. So this is something you can wear. It's not something you can wear and not worry about damaging it. You need to be a little bit careful, it's gonna scratch, it's gonna pick up marks and abrasions and things, but you know, it's wearable. So don't don't worry too much.

SPEAKER_00 14:16

It's also quite cost-effective generally, unless you're talking about certain kinds of tourmaline, so you don't have to like really, really worry about it, I find. We've replaced a few. And it's not a lot of things.

SPEAKER_02 14:26

It's quite difficult to replicate a colour though, because like they're all so very distinct and individual. It's one of the one of the gem varieties that is that can come in really unique colours and you might not find another one that looks that colour.

unknown 14:41

Yeah.

SPEAKER_00 14:41

Which is a great shopper stone because there's always something new and interesting to see in the tourmaline tray. So if you just like shopping, this is a really good one to get into. Uh some more boring facts, of course, if you guys are doing your diploma, it will be on the sheet on the back. Always worth checking, but it's also worth kind of having a general understanding of. So the RI is 1.2 to 1.65 with a birefringence of 1.62.

SPEAKER_02 15:04

Just just you know.

SPEAKER_00 15:05

What what?

SPEAKER_02 15:06

You said 1.2. Oh, 1.62.

SPEAKER_00 15:09

1.62. Sorry.

SPEAKER_02 15:10

Yeah.

SPEAKER_00 15:10

1.62 to 1.65. Thank you, Simon.

SPEAKER_01 15:13

Yep, we're welcome.

SPEAKER_00 15:14

Birefringence of 0.014 to 0.021.

SPEAKER_02 15:21

So that means that we're going to be able to have potentially visible doubling of the back facets because the birefringence is such that you might be able to see that. So that's another thing to to have a look at.

SPEAKER_00 15:31

The SG is three or three point one, and this queen is uniaxial negative, which I hope to never have to identify in a stone again.

SPEAKER_01 15:39

Why?

SPEAKER_00 15:40

What's another important I just find it uh deeply annoying.

SPEAKER_02 15:43

Okay, fair enough.

SPEAKER_00 15:44

What's another important thing to note about Torblade Simon?

SPEAKER_02 15:48

That it's strongly preach. So if you look down the C-axis, you're going to it's the stone's gonna be much darker than if you're looking across the crystal, which is an important factor when you're actually going to cut the stone. And uh if you've got a particularly dark stone, you might want to cut it with the table uh facet presenting itself across the crystal, so it lightens it, or vice versa. Although, because they're quite long and thin, you might not get a very big yield or a very big stone if you're trying to cut the table sort of running perpendicular to the length of the crystal, if you see what I mean. Um actually what you'll find when you see cut tourmaline is that the keel, so like the pavilion of the stone, is more or less the outer edge of the crystal itself. So where when you've got these sort of like uh triangular coming to a point, the keel's gonna kind of be just that, and they've just got sort of polished it off, put some basets on it and not really lost any of the material at all. So you're gonna kind of see more unusual shape stones with tourmalines than you would with others because of its crystal, because of its uh crystal form, if you like.

SPEAKER_00 16:56

Yes. And that is true, I've noticed that actually.

SPEAKER_02 16:59

Yeah, so you might so uh and that can occasionally cause problems with setting them because they can be quite chunky coming up to the girdle. So you've got quite a fat edge because they don't really sort of have those facets that other stones were, and they don't sort of come in quite as as neatly.

SPEAKER_00 17:15

Neatly I have a very chubby pink tourmaline that I bought myself that I am like, I don't actually know if this is gonna be a pain in the ass because it's so the bottom is so fat.

SPEAKER_02 17:24

Yeah, and that's that's down to its crystal form, basically, it's crystal habit.

SPEAKER_00 17:28

Very beautiful though. Someday, someday I'll have it catted and set. There is one more property of tourmaline that we haven't touched on yet. It's quite cool, and it takes us back to the Dutch East India Company because, like the conquistadors and the Scars Guards, we cannot seem to be able to do that. You're obsessed with talking about it It's not that I love them, it's that they weren't everyone's fucking business.

SPEAKER_02 17:48

They did every get involved in all manner of shit.

SPEAKER_00 17:51

All right, we're getting back in our time machine, y'all. So Tourmaline, as we have touched on, was often mistaken for other stones, just like poor Spinel. But she has she can do something that Spinel cannot do, and that no other stones, except I think one other stone, can do. So that is part of what started setting her apart from the things that people were hoping that she was. So people were sending her in these sort of mixed gravels from Sri Lanka, and that's how she got her name. So the name Tourmaline is derived from the Sinhalese word Tor Male. Toramoli.

SPEAKER_01 18:23

Okay.

SPEAKER_00 18:24

Yes. Essentially that means mixed gemstones. So this was the, you know, far before a lot of the tests that we talk about in this podcast. It was the days of the Black Princess Spinel being mistaken for a ruby, and there was with no way to tell the difference between stones, a lot of which were coming out of the same gravels, things were distorted by color, and like that was just what it was. But one thing that tourmaline can do is pull ash, which sounds weird, but it has its own name. The Dutch would call it Ashen Trekker, and it wasn't actually a new observation. Tell me a little bit more about who was first observing this property that tourmaline had.

SPEAKER_02 19:00

So according to S. B. Lang's 2004 article, a 2400-year history of pyroelectricity, the Greek philosopher Theophratus described a stone. He called it Lingurian, and we think it might be tourmaline, and it could attack straws and bits of wood.

SPEAKER_00 19:18

Attract, not attack.

SPEAKER_01 19:21

Yeah, attract.

SPEAKER_02 19:23

Sorry, I am hung over. So yeah, it could attract it could attract things, really. So it was like, what's got what's going on here?

SPEAKER_00 19:33

Yes, it was kind of a party trick.

SPEAKER_02 19:35

Yeah, okay.

SPEAKER_00 19:36

Then you enter the 18th century, and one thing about the 18th century is everybody was using a lot of coals and they were really bored. So you're in a situation where there's a lot of ash around and there is no TikTok, and there's a bunch of Europeans who are just hanging out, really paying attention to what their ash was doing from their fires. So Johann Gorg Schmidt and Louis Lemary both noticed that one particular stone from these Sri Lankan parcels was getting dirty. And what they noticed was it would get hot, and as the stone heated up, it would start pulling the ash from the hot coals. And then when it cooled, the ash would all fall off. So they started doing this party trick where like they'd heat up the stone, get a bunch of ash onto it, move the stone, and as the stone cooled, it would drop the ash somewhere else. So ash pulling, that's where that comes from.

SPEAKER_01 20:25

Nice.

SPEAKER_00 20:26

And it felt like magic, but as we all know, Simon has thoroughly debunked magic as of our last episode.

SPEAKER_01 20:33

So yeah.

SPEAKER_00 20:35

If it isn't magic, Simon, you hater, what is it?

SPEAKER_02 20:38

It's called pyroelectricity. And that basically means that, like you said, when tourmaline gets hot, it attracts things to it. Uh a bit like static electricity, I suppose. Tourmaline is pyroelectric. So it gets warm, it develops an electrical charge. When it cools, that charge goes away. So when it's warm, the electrical charge is dragging the ash to it, getting stuck to it, and then as it cools down, it's letting it go, like you said. And Craig told us that if you have sort of tourmaline in a shop window, particularly back in the day when uh we didn't have LEDs, shop windows like trust me, get really, really hot. And like at the end of the day, when you're like tasked with taking the jewellery out of the window, it's in the summer, it's like unbearable because you've got the light being down on the shop window, which is heating the bloody place up, and then you've got the lights heating the place up because they've been on all day, but also it's gonna heat your stones up. So if you've got tourmaline in the window, well, if the tourmaline is getting hot, then what's it doing? It's attracting little dust particles to it. So your stones are gonna look dirty.

SPEAKER_00 21:44

All the creepy stuff that's in your window that you can't be bothered to vacuum out that's going straight onto your tourmaline.

SPEAKER_02 21:49

Yeah, you don't you don't want that. You don't want your stones looking dusty and dirty. They're supposed to be looking lovely and you know, appealing to people. Um, so yeah, that is that's a tricky. thing with having these these things in your in your window. Amethyst also is a something that does the same thing. Incidentally, Amethyst and Tourmaline are both piezoelectric as well. So that means they create a charge when they're compressed or squeezed. So yeah, there's a lot going on with with um tourmaline and its vibrations and its attractive energy.

SPEAKER_00 22:19

There is indeed. So shout out to all the really bored Dutchmen who nailed that one down for us plus everyone else that I'm sure we're forgetting or haven't made it into the holes of history. So we have talked about what tourmaline is. Let's talk about how it forms. Let's caveat this Simon by saying neither of us is like a huge geology head.

SPEAKER_02 22:37

That would be accurate. My schists and my fucking gneisses I I don't know the difference, I'll be honest. I can't remember. I've written here I tried to fucking cram it in for the exam.

SPEAKER_00 22:49

But like that the worst revision day was the the geology day. It's just so many definitions of things I actually fundamentally don't really care about.

SPEAKER_02 22:58

Sorry, geologists I don't dislike geology I just can't remember it. I've got nothing against it. It's just hard to remember.

SPEAKER_00 23:04

Once you start to understand it like it does make sense but it's a lot of definitions. Yeah.

SPEAKER_02 23:09

Same same with most things. If you understand it you can remember it. I don't necessarily really understand it very well. Exactly.

SPEAKER_00 23:15

So if there is any nuance here that we've missed guys please feel free to tell us in the comments or you can email us because we want to know where we're going wrong. But I do think that this is by and large pretty correct and we've tried to break down some of the terminology for you guys so that you know what we're talking about. We're not just going to spit it at you. All right are we ready?

unknown 23:33

Okay.

SPEAKER_00 23:34

Gird yourself. Just just what you want to be doing really hungover. Tourmaline is found in pegnetites and other granitic rocks. If you remember nothing else, remember that. Now let's break it down because how tourmaline looks and behaves actually has a lot to do with how it's formed and it does make sense once you start to understand.

SPEAKER_02 23:49

We are we are probably talking mostly at this point about a specific variety of tourmaline which would be the Lbite variety. Would that be correct?

SPEAKER_00 23:58

Yes.

SPEAKER_02 23:59

Lbite variety Which again we'll get into more we're going to get into and we'll go into in fact Lucinda's going to rank the varieties of tourmaline in terms of how which one her favorites are. But this is most specifically about the L bite variety. We'll we'll get on to what that means.

SPEAKER_00 24:17

Exactly. Alright so let's talk about first what a pegmatite is because this is where the action is happening. So it's defined by Gemma as quartz as quote a coarse grained igneous rock commonly composed as as of quartz and feldspar. Pegmatites may contain large crystals of rarer minerals and are a valuable source of gemstones. Great. What do we need to be taking away from that Simon?

SPEAKER_02 24:43

So basically an igneous rock is when molten rock or magma has cooled and solidified. So this extreme heat and sort of chemical chaos transforms and it it's kind of like a big hot bath of chemicals and pegmatites are like the later stage of crystallization from mineral rich water. So it's basically when all the sort of common minerals and elements have already sort of crystallized and come out of the mixture and we're left with like the the rarer like the the the the you know like the probably the cooler ones the ones that are sort of creating the most drama left and they're precipitating out at the later stage and forming these gemstones. So it's kind of at the final stages of this cooling process.

SPEAKER_00 25:32

Exactly but they're also deep underground and so this cooling is happening very slowly which means that all of the drama is actually a range it has a lot of time to figure out the best possible arrangement not necessarily not, you know, to create the coolest stuff, but it often does create the coolest stuff because it's got plenty of time. It's not stressed. It's just taking its time. So you've got chemically chaotic magma trapped in the Earth's crust, cooling very slowly lots of water, lots of elements, lots of chemicals, lots of time equals really beautiful tourmalines in particular. And the liquid inside of the pegmatite is changing as the crystals grow. So as we learned earlier the color of tourmaline depends a lot on who these guest star elements are as it's forming and it's really flexible. So as the liquid is changing inside the pegmatite and the environment is changing, the stone that it's is being created is also changing, which is why you have this amazing color zoning. It's why you have bicolor or particolorines it's why watermelon tourmaline exists at all. And it's also why tourmaline is one of the coolest stones in the world just objectively speaking would you say Simon?

SPEAKER_02 26:38

Yeah I would like I really would that's that's that's good. And the like bicolor tourmaline is really cool. The two sort of different colours literally side by side as obviously the chemicals have and the the elements have sort of shifted around and sort of created these different colours. It looks looks really cool.

SPEAKER_00 26:56

It does look really cool. But not every member of the family can be a rock star. Don't make me reference the Scarsgard again but I will. So you have your famous Scargards but you also have your not famous scarsgards. I think at least one of those siblings is a nurse or something. And the more emotionally healthy but objectively less valuable members of the Tourmalines family grow in schists and marbles. Simon, what do we make of that?

SPEAKER_02 27:20

So the previous ones we were talking about with the L-bite ones, these are like these have got sheer names to be fair. The Dravites and the Uvites they sound like characters from Lord of the rings or something. But yeah so basically a schist is a medium grade foliated metamorphic rock characterized by its ability to split easily into thin flakes or plates. Um and is so Lucinda's written here not just Grecian sort of statues. This is one the Rose was hitting clearly yeah she's referring to Grecian statue buttocks I think here is not all that marble is marble is a recrystallized limestone actually mostly consisting of calcite.

SPEAKER_00 28:01

Yes and what both of these have in common and where they differ from pegmatites is that they're solid rock. So they're being altered by pressure not by heat. So nothing is sloshing around and like taking its luxurious time to grow. What's happening instead, Simon?

SPEAKER_02 28:16

Yeah so basically there are fluids being released from nearby places and sort of oozing over these pressurized rocks. With these with like the schists and like the marble there is less sort of chemical liquid involved and maybe a bit more pressure and heat. So it's like metamorphic reaction rather than crystallization through precipitating minerals in liquid. So yeah more more pressure based I would say.

SPEAKER_00 28:42

Yes. And in the marbles the situation essentially is boron rich fluid meets calcium rich rock under intense heat and pressure and tourmaline pops out. Tourmaline is their baby. Often both of these stones are aluminum rich or iron bearing which means pretty boring colors frankly and they don't have a lot of space and time to grow so they're going to be included they're going to be small. You can tell when a gemstone has been formed by pressure because they freak out a little bit. And obviously they're growing alongside other gem species. So you get the least glamorous of the tourmalines but of course everybody is gorgeous in their own right isn't that true Simon 100% yes So now's the moment you have all been waiting for we are going to talk about some varieties of tourmaline this is an overview of the family and then next time we talk about tourmaline we'll do some deep dives we'll tell some stories about some of the more famous and interesting varieties.

SPEAKER_02 29:34

No doubt including conquistadors there may be a conquistador. Okay fine well as long as as long as there's a conquistador what did you do?

SPEAKER_00 29:42

I just dropped my extension cord on myself. All right so one thing to note about tourmaline is there are lots of varieties and there is some disparity between the quote unquote trade names i.e what you think you're shopping for what you think you're buying and then the true scientific names this is an isomorphous series so there's a lot of detail in terms of what stones get called what and unless you're going to go to Switzerland and be like one of the really serious top gemologists you probably don't actually need to know that for the purposes of what we're doing now, which is obviously entertaining you, but also educating you for a GemA or an uh GIA kind of level certification, the trade names are probably going to be the most useful. Sometimes they do overlap and intersect. What do you think, Simon?

SPEAKER_02 30:27

Yes, I would agree. So keep it keep it as simple as possible I think is probably for the best.

SPEAKER_00 30:33

Okay so I have ranked these in the order of my least favorite to my most favorite. I know that Simon his ranking is different.

SPEAKER_02 30:41

Not wildly different I'll be honest.

SPEAKER_00 30:43

I think there's a one swap that we would make but we'll face that when we come to it. So first off Simon where are we starting on the least popular scale?

SPEAKER_02 30:51

So the shawl so this is black tourmaline and it's basically just black Panny who studied with us got very excited when we were at the GemA conference the first time we went because in a bargain bin of gemstones she found a black tourmaline and was very happy about it.

SPEAKER_00 31:10

So you know maybe there was a period of time where every time I went to an event with Panny she was buying a black gemstone of some kind.

SPEAKER_02 31:17

She bought a black sapphire light about light return. She just wants it to be black.

SPEAKER_00 31:22

She had the most beautiful wedding by the way it was so nice.

SPEAKER_02 31:25

She did yes thank you so much for inviting us we had a very good time didn't we? We did um but yeah basically this is really iron rich and it's really dark and not Lucinda's favorite.

SPEAKER_00 31:34

Then you've got Dravite. This is very dark green sometimes brown to black this is what happens when magnesium takes the wheel also not my favorite.

SPEAKER_02 31:44

Okay. And then you've ranked in third spot L bite which is which is sort of like the umbrella one for all the nice colourful ones basically.

SPEAKER_00 31:54

Yeah so we're now entering good territory.

SPEAKER_02 31:56

Yeah so all the so all the nice ones like the nice bright coloured ones and the and the you know the the good ones basically let's let's not be around the bush the good ones are L-bite variety tourmalines and then there are various ones within the L-bites which Lucinda has kindly ranked for us as well.

SPEAKER_00 32:13

Yes.

SPEAKER_02 32:14

And this is where we start to draw the line between this is interesting and it's sort of attracting ash to oh my god this is actually really lovely and could substitute for a very expensive gemstone and look very beautiful or indeed be an extremely expensive gemstone in its own right. These are lithium rich and they form in the pegmatites that we spoke about and this is where you get the big colours, the large crystals lots of variety lots of colour lots of mixing of colours there's like bicolours like we were talking about your watermelons and all that stuff. They tend to be quite clean large crystals as we said and uh and within that category Lucinda has ranked the ones that she likes.

SPEAKER_00 32:57

So take that away at the bottom of the list indicolite it's blue it doesn't move me what do you think of indicolite?

SPEAKER_02 33:05

It's quite sapphire isn't it? Hmm but it's that kind of muted darker blue probably slightly darker yeah um can be very lovely but I would probably agree not necessarily my favourite what's next Simon the watermelon ones so we spoke to you a little a minute ago about how they are green on the outside and pink on the inside. The only drawback with watermelon tourmaline is that you kind of so if you've got like a baguette and you're going to cut a slice of baguette you've got like this kind of small sort of disc bit of bread. That's kind of all you can do with a watermelon tourmaline because you need to have you need to have the outer you need to have the outer which is the green which can be quite sort of thin and you can't really facet it, you can't cut it because you're going to be cutting the green away and then you just wound up with the with the pink in the middle. So you kind of really have to be very one note isn't it?

SPEAKER_00 33:57

It's mostly in slices.

SPEAKER_02 33:58

It's like a slice or a slab of of tourmaline so whilst it's very pretty because it's looks like watermelon and it's got this lovely pink colour on the inside and the green on the outside it's not really a faceted or cuttable gem variety because you're going to cut the green away and it's then not going to be what it is which is why the bicolour ones with the same two colours the pinks and the greens side by side are very popular and often called watermelon because they're the colours of the watermelon, but obviously strictly speaking not watermelon because the red's not the inside and the green's not on the outside.

SPEAKER_00 34:29

So slices though in terms of like desirability and price and you know is it is it quote unquote better to have a beautifully faceted stone that is not officially a watermelon tourmaline or is it better to have an official watermelon tourmaline? Like it's it's a kind of microcosm of that tension in the industry I think.

SPEAKER_02 34:47

I'd say the pink and green faceted like emerald cut I love them. I really like them.

SPEAKER_00 34:52

In fact I've got anything party coloured to me is my favorite I think there's such a cool sapphire crystal mist at the minute over here. It's like essentially colourless but then it's like deep deep inky blue but just on the very edges at the top and the bottom it's so cool.

SPEAKER_02 35:07

That does sound cool. I just recently bought a tourmaline at work um and it's kind of colourless in like two thirds of it and then it's got like a little green tip of the on the on the um on the emerald cut and that's really cool. I think that's it's really nice. I'll get a picture of it and we'll put it up on the um on the Instagram.

SPEAKER_00 35:27

This is the ch the charm of some gemstones like they have so much personality don't they?

SPEAKER_02 35:31

Yeah definitely and tourmaline is one of those that has a lot of personality and what's nice about tourmaline is so when you've got your bicolour sapphires and things they tend to be like the two colours are kind of like swirling around and they're not they're not quite as defined whereas tourmaline you get really definite sort of distinction between the two colours. Like in an amateur for example you get like it goes from one colour to the other colour and they can almost sit like with a perfect dividing line between them and that is super cool.

SPEAKER_00 35:58

Super cool all right now we're up at the top two. So guys get your bets in what's going to be Lucinda's favorite run her up. This I would say Simon is probably your favorite 100% she's expensive she's famous if you were going to know a tourmaline without being a gemologist or serious jewelry person this is probably the one that you would know drum roll. It is the Periba tourmaline so these are neon blue they're absolutely stunning they're extraordinarily expensive and they come from unreal. Yeah they come from Brazil. Lots of people really love them. There are now type tourmalines coming out of other places we'll talk about this more next week because they really do deserve a spotlight. They're just a force in and of themselves.

SPEAKER_02 36:40

My wife has a peribatourmaline a like an elongated pear shape stud as one of her like mismatched stud earrings that she has and one of them's a peribatourmaline and um it was it's like I don't know 30 points or something and it was like wildly expensive. The thing that they say about peribatourmaline is um think of Windeline. So that sort of really neon like you know that liquid that you clean your windows with and it's literally like that. It looks chemical it looks it's like bright it sort of glows like a chemical blue colour. It's yeah really pretty amazing in its finest forms is yeah nuts and the price is ridiculous.

SPEAKER_00 37:21

Yeah. Fortunately for me that is not my favorite one.

SPEAKER_02 37:23

Simon tell me about my favorite gemstone my favorite one apparently is the Rubulite Yes I love it of which I had a very fine example in my hand on Friday and we put it on our Instagram.

SPEAKER_00 37:37

Yes and actually you guys are pretty good with that. That was a hard one to ID by eye but the last time I checked it Rubulite was was up there as the most selected tell me more about it.

SPEAKER_02 37:48

So it's basically I mean the clue's in the name really is kind of imitating Ruby and it's um it's almost a Ruby like which is how you might remember it. Rubelite Ruby like because it's red. Basically that but I like a quite it can be lots of sort of shades of red but it's quite a sort of deep sort of moody red I would have said yeah and it's my favorite by far I am not alone in this someone very famous also loves Rubulite.

SPEAKER_00 38:15

We will talk about that next week. So tune in next time to get the goss there is obviously a lot to say about these varieties and even more on testing tourine full stop but as I say we will be back next week or maybe not next week but soon with a part two where we can get a little into the testing and also each of these varieties and their lore and their history.

SPEAKER_02 38:37

And we can talk about the inclusions because obviously tourmaline Trichites I know I know you love trikites that's my favorite of the inclusions.

SPEAKER_00 38:45

In the meantime let us leave with the localities so you can start imagining where we'll be taking you to next I'm sure there will be a conquistador. Simon according to Jemai where are we headed?

SPEAKER_02 38:55

So we find particularly fine quality tourmaline in places like Afghanistan Brazil obviously because that's where Pariba Pariba's a place by the way is Pariba state is in Brazil. So the they come from Brazil. Madagascar Mozambique Namibia Pakistan Russia Tanzania and the USA and special mention to Nigeria because actually you get some really good periba type tourmaline from there too. Note the language Pariba type Pariba type I don't actually think you have to call them on a gem lab report Pariba type I think you can call them Pariba. I think you can talk about it there's a sp very specific thing that a Periba type or a Pariba tourmaline has to have in its chemical composition but we'll leave that till next time.

SPEAKER_00 39:42

Exactly so we will see you next time where California and China collide and we will be talking about a stone so stunning that it defies even gemologists and revives the fortunes of its brothers and sisters we will see you next time in sunny San Diego.

SPEAKER_02 39:57

Have you ever Dodgers he's in Los Angeles at the minute and he is heading down to sunny San Diego in the next couple of days.

SPEAKER_00 40:08

Lovely we'll tell him have a look around for some tourmaline mines while he's down there.

SPEAKER_02 40:12

That's true. Yeah good idea.

SPEAKER_00 40:13

Jeff also said that that's kind of where he cut his teeth with mining and um when we when we spoke to him down in the sort of tourmal I'm not just saying this because I'm from there but California very special place.

SPEAKER_02 40:24

Big tourmalines I don't know if any I don't know if I've said to any sneezes I don't know if I've said this on the podcast but I'm actually going to um Oregon in the beginning of June. And uh yeah I'll um I'll I'll I'm make a specific effort to report back from Oregon and any gym things I find there.

SPEAKER_00 40:44

Because definitely do.

SPEAKER_02 40:45

As we know there's gemstone specific Oregon for ones there are some of our favorites in fact. Yes absolutely fabulous well thank you for joining me to talk about tourmaline Simon no I enjoyed that thanks for the um conquistador lesson.

SPEAKER_00 40:59

I'm sure there'll be a conquistador next time too don't worry guys he's always with us our unnamed conquistador once again thanks for hanging out with us guys you can get us on Instagram at Facet NationGemology. You can get us on emailfacetnation at fascination.co.uk Simon are you still posting on our TikTok? Okay we're gonna get that up and running for you guys as soon as I figure out how to log in what else any other anything else to report Simon?

SPEAKER_02 41:26

Don't think so no we've got an very exciting and interesting interview coming up um specifically interesting for me and my studies at the minute so uh that might give you a clue but uh yeah that's that's all to be revealed in the coming weeks.

SPEAKER_00 41:45

Yes well thank you so much for listening everyone we will see you on socials and barring that we'll see you right here next week.

SPEAKER_01 41:51

Ciao