 Nagi Arato : Phew... |
(0:00:06.01) |
 Ruri Tanigawa : Is this the rock you're researching? |
(0:00:06.99) |
|
Nagi Arato : Huh? Yeah, it is. |
(0:00:09.19) |
|
Ruri Tanigawa : Does it have pretty minerals? |
(0:00:11.11) |
|
Ruri Tanigawa : Or is it a clue to finding cool gems? |
(0:00:13.17) |
|
Nagi Arato : This isn't that kind of ore. |
(0:00:16.04) |
|
Nagi Arato : It's your typical igneous rock. |
(0:00:18.00) |
|
Ruri Tanigawa : So it's just a normal rock? |
(0:00:20.28) |
|
Nagi Arato : These have a lot of meaning, too. |
(0:00:22.10) |
|
Ruri Tanigawa : It's way too hard for beginners. |
(0:00:24.22) |
|
Ruri Tanigawa : Right, Imari-san? |
(0:00:27.53) |
 Youko Imari : Are you saying that we're the same? |
(0:00:29.23) |
Ruri Tanigawa : Come on! Let's look for rocks
like sapphire and fluorite. |
(0:00:33.08) |
|
Ruri Tanigawa : You know, pretty rocks? |
(0:00:36.65) |
|
Youko Imari : Well, maybe Senpai has her own reasons. |
(0:00:38.35) |
|
Ruri Tanigawa : Nagi-san's reasons, huh? |
(0:00:42.96) |
|
Nagi Arato : Hmm... |
(0:00:50.52) |
Youko Imari : Ugh... It doesn't say
the one thing I'm looking for. |
(0:00:51.39) |
|
Youko Imari : Why? It's like it's on purpose. |
(0:00:56.14) |
|
Ruri Tanigawa : Hey, aren't you two working too hard? |
(0:01:00.43) |
|
Ruri Tanigawa : You should take a break every now and then. |
(0:01:03.92) |
|
Nagi Arato : Okay, then wanna go find some agate? |
(0:01:08.58) |
Ruri Tanigawa : Wow! It's so pretty,
and we've got it all to ourselves! |
(0:02:42.64) |
|
Nagi Arato : This beach isn't for swimming. That's why. |
(0:02:45.55) |
|
Ruri Tanigawa : So this is our site? |
(0:02:47.60) |
Nagi Arato : Yup. This place only appears
when the tides are low. |
(0:02:48.94) |
|
Nagi Arato : It's a secret site not many people know. |
(0:02:52.09) |
|
Ruri Tanigawa : I like the sound of that. I bet we'll find tons! |
(0:02:53.86) |
|
Ruri Tanigawa : Did these rocks all come from the river? |
(0:02:57.47) |
Nagi Arato : No, they were likely part of a
larger rock mass on the seafloor. |
(0:03:00.03) |
Nagi Arato : They ended up here after being dislodged
by wave erosion and seismic activity. |
(0:03:02.81) |
|
Ruri Tanigawa : Whoa... |
(0:03:06.35) |
|
Ruri Tanigawa : So what does agate look like? |
(0:03:08.09) |
Nagi Arato : It has a banded pattern.
You'll know it when you see it. |
(0:03:10.75) |
|
Ruri Tanigawa : All right, let's do this! |
(0:03:13.63) |
|
Youko Imari : It's so cool and refreshing. |
(0:03:20.92) |
|
Ruri Tanigawa : Imari-san, you're resting already? |
(0:03:23.02) |
|
Youko Imari : Sorry, I'm more of a homebody. |
(0:03:26.60) |
|
Youko Imari : You sure have a lot of energy, Ruri-chan. |
(0:03:29.06) |
|
Ruri Tanigawa : I do today! |
(0:03:30.71) |
Ruri Tanigawa : Compared to studying
sand through microscopes, |
(0:03:32.53) |
|
Ruri Tanigawa : looking for big rocks is a piece of cake! |
(0:03:35.05) |
|
Youko Imari : Good point. |
(0:03:38.39) |
|
Nagi Arato : Agate, where are you? |
(0:03:39.39) |
Nagi Arato : Banded pattern, banded pattern,
banded pattern... |
(0:03:40.65) |
|
Nagi Arato : I don't see any banded patterns! |
(0:03:47.88) |
|
Nagi Arato : Find any? |
(0:03:57.22) |
|
Ruri Tanigawa : Nope, not yet. |
(0:03:58.33) |
|
Nagi Arato : Here, this is it. |
(0:04:01.62) |
|
Ruri Tanigawa : You found one? |
(0:04:02.86) |
|
Ruri Tanigawa : Wow! It really is
patterned! And red! |
(0:04:03.56) |
Nagi Arato : It basically has the same
composition as quartz. |
(0:04:06.94) |
|
Ruri Tanigawa : How? It looks so different! |
(0:04:09.48) |
Nagi Arato : Agate's bands are easy to understand
when you learn how they form. |
(0:04:11.77) |
Nagi Arato : First, hot water flows
into cavities in the rock. |
(0:04:15.58) |
Nagi Arato : Then, silicon dioxide precipitates,
forming a layer of very fine crystals. |
(0:04:18.94) |
Nagi Arato : This cycle repeats, gradually
creating multiple layers. |
(0:04:24.99) |
|
Ruri Tanigawa : What about the red color? |
(0:04:29.96) |
Nagi Arato : The coloring is from impurities.
Red usually means iron oxide. |
(0:04:32.27) |
|
Nagi Arato : Although they have the same composition, |
(0:04:38.36) |
|
Nagi Arato : quartz forms as a single large crystal, |
(0:04:39.85) |
Nagi Arato : while agate is made of
many layers of tiny crystals. |
(0:04:42.55) |
|
Nagi Arato : It's only natural they have different names. |
(0:04:45.40) |
|
Ruri Tanigawa : I gotta hurry and find my own! |
(0:04:47.81) |
|
Youko Imari : Found one. |
(0:04:50.98) |
|
Ruri Tanigawa : You've gotta
be kidding! |
(0:04:53.75) |
|
Ruri Tanigawa : I was working so much harder! |
(0:04:55.06) |
|
Nagi Arato : You can't really argue with luck. |
(0:04:57.42) |
|
Youko Imari : Maybe I'll make a comma-shaped bead. |
(0:05:00.31) |
|
Ruri Tanigawa : Hmph! |
(0:05:02.66) |
|
Ruri Tanigawa : Are they really here? |
(0:05:06.91) |
|
Ruri Tanigawa : Maybe those were the last two. |
(0:05:09.71) |
|
Ruri Tanigawa : Ow! |
(0:05:13.33) |
|
Ruri Tanigawa : What the heck is this rock? |
(0:05:15.44) |
|
Ruri Tanigawa : It's the only one this jagged and big. |
(0:05:16.97) |
|
Ruri Tanigawa : Out of my way! |
(0:05:19.92) |
|
Ruri Tanigawa : Huh? |
(0:05:22.19) |
|
Ruri Tanigawa : A banded pattern! It's agate! |
(0:05:25.77) |
|
Ruri Tanigawa : I found some! Come here! |
(0:05:34.64) |
|
Ruri Tanigawa : There were two right here by this rock. |
(0:05:37.50) |
|
Ruri Tanigawa : You'll find tons here. |
(0:05:39.82) |
|
Youko Imari : Nice. But isn't that just a coincidence? |
(0:05:41.88) |
|
Ruri Tanigawa : Really? I was only trying to help out. |
(0:05:44.84) |
|
Nagi Arato : Actually, Ruri might be spot on. |
(0:05:48.49) |
|
Nagi Arato : Over here. |
(0:05:51.06) |
|
Youko Imari : These blocks are pretty worn down. |
(0:05:53.76) |
|
Ruri Tanigawa : So that's where that jagged rock came from. |
(0:05:55.19) |
|
Nagi Arato : You think the waves caused it? |
(0:05:57.88) |
Ruri Tanigawa : Water can do that?
But the other blocks are fine. |
(0:05:59.75) |
Nagi Arato : This is just my theory, but wave energy
must concentrate here during high seas. |
(0:06:03.31) |
Nagi Arato : If I could see the natural terrain,
I could say for sure. |
(0:06:08.63) |
|
Nagi Arato : Here's another one. |
(0:06:13.37) |
|
Ruri Tanigawa : I told you there's tons! |
(0:06:14.19) |
|
Ruri Tanigawa : Let's look here. |
(0:06:15.78) |
|
Ruri Tanigawa : Come on, agate! |
(0:06:18.15) |
|
Ruri Tanigawa : Found one! |
(0:06:22.09) |
|
Ruri Tanigawa : That makes three. |
(0:06:23.76) |
|
Youko Imari : Is this...? |
(0:06:25.83) |
|
Ruri Tanigawa : You find one too, Imari-san? |
(0:06:27.45) |
|
Youko Imari : Senpai, can you take a look? |
(0:06:29.31) |
Ruri Tanigawa : It's a pretty red rock,
but it doesn't have bands. |
(0:06:32.11) |
|
Nagi Arato : Yup, it's chalcedony. |
(0:06:38.10) |
|
Youko Imari : Thought so! |
(0:06:40.02) |
|
Ruri Tanigawa : What's that? |
(0:06:40.93) |
|
Youko Imari : It's agate without the banded pattern. |
(0:06:42.01) |
|
Youko Imari : That's the only difference. |
(0:06:44.28) |
|
Ruri Tanigawa : It gets its own name for that? |
(0:06:45.90) |
|
Ruri Tanigawa : Hang on... |
(0:06:48.18) |
|
Ruri Tanigawa : So one crystal makes a quartz crystal, |
(0:06:49.67) |
|
Ruri Tanigawa : and tiny crystals in layers makes agate, |
(0:06:51.53) |
|
Ruri Tanigawa : while without layers is chalcedony? |
(0:06:53.86) |
Youko Imari : Then there's jasper,
which has more impurities. |
(0:06:55.74) |
|
Ruri Tanigawa : Uhh... there's more...? |
(0:06:59.70) |
|
Nagi Arato : Ultimately, they're all varieties of quartz. |
(0:07:01.56) |
|
Ruri Tanigawa : You're just trying to fry my brain! |
(0:07:08.12) |
|
Ruri Tanigawa : I was afraid I wouldn't get any. |
(0:07:13.75) |
|
Ruri Tanigawa : Good thing I found that spot. |
(0:07:16.30) |
Ruri Tanigawa : You said that spot
is vulnerable to wave force, |
(0:07:19.11) |
|
Ruri Tanigawa : but what does that have to do with agate? |
(0:07:21.43) |
|
Nagi Arato : Good question. I'm not sure. |
(0:07:23.98) |
|
Ruri Tanigawa : You don't know? |
(0:07:25.38) |
|
Nagi Arato : It was the sole obvious difference. |
(0:07:26.63) |
|
Nagi Arato : My theory might be right, or it might not. |
(0:07:28.62) |
|
Ruri Tanigawa : So you have no idea? |
(0:07:32.06) |
|
Ruri Tanigawa : That's definitely gonna bug me. |
(0:07:34.01) |
|
Nagi Arato : Will it? |
(0:07:37.32) |
|
Nagi Arato : Okay, let's see... |
(0:07:39.32) |
Nagi Arato : Waves exert more force when seawater
is funneled through a narrow space. |
(0:07:41.96) |
Nagi Arato : Based on this, we can infer that this spot
collects rocks transported from a wider area. |
(0:07:48.84) |
Nagi Arato : This would explain
how agate accumulated here. |
(0:07:53.44) |
|
Nagi Arato : Or maybe it's not that complicated. |
(0:07:57.18) |
Nagi Arato : This spot could simply be
near an agate deposit. |
(0:07:59.06) |
|
Ruri Tanigawa : That makes sense. |
(0:08:03.06) |
|
Ruri Tanigawa : Yup, I feel much better! |
(0:08:04.47) |
|
Ruri Tanigawa : Imari-san, can I see the ones you found? |
(0:08:06.40) |
|
Youko Imari : Here are mine. |
(0:08:09.06) |
|
Ruri Tanigawa : That red chalcedony is so cool. |
(0:08:11.22) |
|
Youko Imari : Want to trade me for yours? |
(0:08:13.71) |
|
Ruri Tanigawa : Yeah! |
(0:08:15.18) |
|
Ruri Tanigawa : Oh, but... this one's pretty. |
(0:08:15.89) |
|
Ruri Tanigawa : And I wanna keep this one, too. |
(0:08:18.08) |
|
Ruri Tanigawa : Hang on, I can't find one to trade... |
(0:08:19.63) |
|
Youko Imari : I'm okay with this small one. |
(0:08:22.38) |
|
Ruri Tanigawa : Really? |
(0:08:24.27) |
|
Ruri Tanigawa : Nagi-san! Can I see yours, too? |
(0:08:26.64) |
|
Nagi Arato : Here. |
(0:08:29.35) |
|
Ruri Tanigawa : That's it? |
(0:08:30.99) |
|
Ruri Tanigawa : I thought you found more. |
(0:08:32.23) |
|
Nagi Arato : These are plenty to take home as specimens. |
(0:08:33.77) |
Ruri Tanigawa : You didn't keep the other ones?
What a waste! |
(0:08:36.09) |
|
Nagi Arato : It's okay. |
(0:08:38.54) |
Nagi Arato : For me, minerals are just
a means, not the goal. |
(0:08:39.93) |
|
Nagi Arato : I only take what I need. |
(0:08:42.22) |
|
Ruri Tanigawa : What do you mean by that? |
(0:08:45.15) |
Nagi Arato : What matters most is
how I use rocks in my research. |
(0:08:47.44) |
|
Ruri Tanigawa : So finding them isn't the end goal? |
(0:08:51.64) |
|
Nagi Arato : Hmm... |
(0:08:54.87) |
Nagi Arato : You know what I wonder
when I find a new rock? |
(0:08:57.03) |
|
Nagi Arato : How did this rock get here? |
(0:09:01.13) |
|
Nagi Arato : What does its journey signify? |
(0:09:04.09) |
|
Nagi Arato : What can this rock teach us? |
(0:09:07.38) |
Nagi Arato : Does it support the validity
of an existing theory? |
(0:09:12.72) |
Nagi Arato : Or does it point toward
a completely new one? |
(0:09:16.42) |
Nagi Arato : Each rock we examine raises
new questions and theories to test. |
(0:09:21.21) |
Nagi Arato : And with every question answered,
we can refine our knowledge. |
(0:09:26.55) |
Nagi Arato : We can learn more about how the world
evolved over 4.6 billion years. |
(0:09:32.33) |
|
Nagi Arato : That history can only be found in rocks. |
(0:09:37.79) |
Nagi Arato : The more rocks I study, the better we
understand the true nature of our world. |
(0:09:41.27) |
|
Nagi Arato : I want to contribute to that knowledge. |
(0:09:50.70) |
|
Nagi Arato : So yeah. I guess that's my reason. |
(0:09:55.63) |
|
Ruri Tanigawa : Wow... That's Nagi-san, for ya. |
(0:10:00.79) |
|
Ruri Tanigawa : You're so cool. |
(0:10:03.78) |
|
Ruri Tanigawa : That kinda stuff never even crossed my mind. |
(0:10:05.14) |
|
Youko Imari : You sure? You really hadn't thought of that? |
(0:10:07.97) |
|
Ruri Tanigawa : Why do you ask? |
(0:10:10.91) |
|
Nagi Arato : Don't you remember? |
(0:10:11.95) |
|
Ruri Tanigawa : What about?! |
(0:10:13.57) |
Youko Imari : What you said earlier.
About how not knowing would bug you. |
(0:10:15.46) |
|
Youko Imari : If you really hadn't thought of it, |
(0:10:22.81) |
Youko Imari : you wouldn't have wondered
about it in the first place. |
(0:10:24.88) |
Ruri Tanigawa : But it's not like I was
thinking anything difficult. |
(0:10:28.68) |
|
Ruri Tanigawa : It just happened. |
(0:10:32.17) |
Youko Imari : I think you might be
crossing over to our side. |
(0:10:36.35) |
|
Ruri Tanigawa : Hey, what do you mean by that? |
(0:10:38.97) |
Nagi Arato : Just so you know, most people don't
even bother looking for localities. |
(0:10:41.46) |
|
Ruri Tanigawa : Sapphire... |
(0:10:50.31) |
|
Nagi Arato : Curious? |
(0:11:07.73) |
|
Ruri Tanigawa : Mmhm! |
(0:11:09.05) |
|
Nagi Arato : This is a graph on... |
(0:11:09.99) |
|
Ruri Tanigawa : Done! All ready to collect sapphire from sand! |
(0:11:20.76) |
|
Ruri Tanigawa : Whoa, talk about eruptions. |
(0:11:30.34) |
|
Ruri Tanigawa : Hey, Nagi-san. You here? |
(0:11:36.68) |
|
Ruri Tanigawa : Okay. On my way down. |
(0:11:38.40) |
|
Ruri Tanigawa : I'll gather sand. |
(0:11:43.38) |
|
Nagi Arato : Sounds good. |
(0:11:44.91) |
|
Ruri Tanigawa : Huh? |
(0:11:53.19) |
|
Ruri Tanigawa : This one's slick like it's been polished. |
(0:11:56.54) |
|
Ruri Tanigawa : And it's green. |
(0:12:00.38) |
|
Ruri Tanigawa : It's kinda pretty. |
(0:12:03.54) |
|
Ruri Tanigawa : Cool, this one's a keeper. |
(0:12:06.20) |
|
Ruri Tanigawa : I'll take it home with me. |
(0:12:07.47) |
|
Ruri Tanigawa : Any big sapphires in here? |
(0:12:09.42) |
|
Ruri Tanigawa : No way, placer gold?! |
(0:12:15.26) |
|
Ruri Tanigawa : Nice! Placer gold! |
(0:12:22.99) |
|
Ruri Tanigawa : It's... placer silver? |
(0:12:27.52) |
|
Ruri Tanigawa : Nagi-san! Look what I found! |
(0:12:31.62) |
|
Ruri Tanigawa : It's gotta be placer silver, right? |
(0:12:33.57) |
|
Nagi Arato : I can't see it this close up. |
(0:12:35.38) |
|
Ruri Tanigawa : Here ya go. |
(0:12:37.79) |
|
Nagi Arato : Ah, not quite. |
(0:12:40.43) |
|
Ruri Tanigawa : Already?! Why? It looks silver! |
(0:12:41.52) |
|
Nagi Arato : Real silver would have some discoloration. |
(0:12:44.43) |
|
Nagi Arato : If you ask me, I'd say it's not silver. |
(0:12:48.03) |
|
Ruri Tanigawa : Then what else could it be? |
(0:12:50.61) |
|
Nagi Arato : Galena, perhaps? |
(0:12:52.75) |
Nagi Arato : I don't see any crystals,
so it could also be artificial. |
(0:12:54.84) |
|
Nagi Arato : Like an iron alloy or something. |
(0:12:58.06) |
Nagi Arato : It's not uncommon for factory alloys
to end up in rivers. |
(0:13:00.83) |
|
Nagi Arato : That's probably our best bet. |
(0:13:04.38) |
|
Ruri Tanigawa : Imari-san, look at what I found! |
(0:13:10.09) |
|
Ruri Tanigawa : What do you think it is? |
(0:13:12.02) |
|
Ruri Tanigawa : I say it's silver! |
(0:13:13.52) |
|
Youko Imari : I'm not sure, but it's definitely not silver. |
(0:13:16.72) |
|
Youko Imari : I've never even heard of placer silver. |
(0:13:19.29) |
|
Ruri Tanigawa : Not you too, Imari-san! |
(0:13:21.13) |
|
Ruri Tanigawa : Can't we study it some more? |
(0:13:22.67) |
|
Youko Imari : It's too small to analyze in our lab. |
(0:13:24.31) |
|
Ruri Tanigawa : But it could be silver. |
(0:13:27.81) |
|
Youko Imari : Did you hear what I said? |
(0:13:29.62) |
|
Nagi Arato : Let's put it to the test. |
(0:13:31.46) |
|
Nagi Arato : If it's silver, it should behave like silver. |
(0:13:33.53) |
|
Nagi Arato : But that's not always immediately visible. |
(0:13:36.30) |
Nagi Arato : Very few of its properties can
be seen with the naked eye. |
(0:13:40.23) |
|
Nagi Arato : These qualities are invisible by nature. |
(0:13:43.62) |
|
Nagi Arato : Unless you run tests to make them visible. |
(0:13:45.95) |
|
Ruri Tanigawa : We're checking how fast it sinks? |
(0:13:48.64) |
|
Nagi Arato : That's right. |
(0:13:51.03) |
|
Nagi Arato : The heavier the object, the faster it sinks. |
(0:13:52.29) |
Nagi Arato : It's a simple test
to visualize specific gravity. |
(0:13:54.54) |
Nagi Arato : For now, we'll compare it
with this copper wire. |
(0:13:58.14) |
|
Ruri Tanigawa : Why copper? |
(0:14:00.67) |
Nagi Arato : Silver has a specific gravity of 10.5,
heavier than copper's specific gravity of 9. |
(0:14:02.15) |
Nagi Arato : On the other hand, other possibilities
like iron alloy are lighter than that. |
(0:14:06.32) |
Nagi Arato : In other words, if this grain sinks
faster than copper, it's silver. |
(0:14:10.88) |
|
Nagi Arato : If it's slower, it has to be something else. |
(0:14:14.65) |
|
Nagi Arato : How's that? Will this convince you? |
(0:14:17.50) |
|
Ruri Tanigawa : Okay. We'll go with that. |
(0:14:21.87) |
Nagi Arato : Technically, its purity and form
may affect the results, so... |
(0:14:25.09) |
|
Ruri Tanigawa : No excuses allowed! |
(0:14:28.81) |
|
Nagi Arato : Let's put it to the test, then. |
(0:14:31.78) |
|
Ruri Tanigawa : Please be silver! |
(0:14:34.02) |
|
Ruri Tanigawa : Sink fast, sink fast... |
(0:14:35.77) |
|
Ruri Tanigawa : It's fast! |
(0:14:39.29) |
|
Ruri Tanigawa : See the difference? It's silver! |
(0:14:40.07) |
|
Ruri Tanigawa : Take that! Just as I said! |
(0:14:42.99) |
|
Youko Imari : No way. |
(0:14:45.31) |
|
Ruri Tanigawa : Whaddya say, Nagi-san? |
(0:14:46.47) |
Ruri Tanigawa : I can be right sometimes too,
you know! I win! |
(0:14:47.91) |
|
Nagi Arato : That was too
fast. |
(0:14:52.82) |
|
Nagi Arato : Silver couldn't possibly sink that fast. |
(0:14:55.69) |
|
Nagi Arato : It may be heavier than copper, |
(0:14:58.17) |
Nagi Arato : but that speed was of a mineral
much denser than silver. |
(0:15:00.43) |
|
Ruri Tanigawa : Not fair! |
(0:15:04.74) |
|
Ruri Tanigawa : You said that test would settle it! |
(0:15:05.77) |
|
Nagi Arato : My bad. |
(0:15:07.65) |
Nagi Arato : But now, there's a chance
it's an even rarer mineral. |
(0:15:09.72) |
|
Ruri Tanigawa : Rarer than silver? |
(0:15:13.87) |
|
Nagi Arato : Let's compare it with gold next. |
(0:15:15.64) |
|
Nagi Arato : If I'm right, this should give us the answer. |
(0:15:24.41) |
|
Ruri Tanigawa : They're the same speed! |
(0:15:32.16) |
Nagi Arato : Which metallic mineral has
the same specific gravity as gold? |
(0:15:34.33) |
|
Nagi Arato : Placer platinum. |
(0:15:38.32) |
|
Ruri Tanigawa : That
platinum? |
(0:15:39.72) |
|
Youko Imari : Yup, platinum. |
(0:15:41.29) |
|
Ruri Tanigawa : This is seriously platinum?! |
(0:15:42.43) |
Nagi Arato : More specifically, it’s a grain composed
of rare metals, including platinum. |
(0:15:45.69) |
Nagi Arato : Those with a higher specific gravity than gold
fall under the platinum group metals. |
(0:15:49.63) |
|
Ruri Tanigawa : So it might not be platinum? |
(0:15:53.00) |
|
Nagi Arato : PGMs are all extremely rare metals. |
(0:15:55.48) |
Nagi Arato : For example, rhodium goes for
several times the price of platinum. |
(0:15:58.77) |
|
Ruri Tanigawa : Th-That much?! |
(0:16:01.99) |
Youko Imari : If it's really platinum,
we should be able to find... |
(0:16:04.07) |
|
Nagi Arato : Yeah, that's the problem. |
(0:16:07.56) |
|
Ruri Tanigawa : Don't tell me you're still not sure. |
(0:16:11.24) |
|
Nagi Arato : Not yet. |
(0:16:13.13) |
Nagi Arato : Whether we can find this green rock
called serpentinite is the final key. |
(0:16:15.06) |
|
Ruri Tanigawa : Serpent? |
(0:16:19.46) |
|
Youko Imari : It's a rock that looks like snake skin. |
(0:16:20.83) |
|
Nagi Arato : Platinum is found within serpentinite. |
(0:16:23.38) |
|
Ruri Tanigawa : Can I see? |
(0:16:26.65) |
|
Ruri Tanigawa : So they're in here. |
(0:16:29.42) |
|
Ruri Tanigawa : Wait, this green rock... |
(0:16:32.15) |
|
Ruri Tanigawa : Um... |
(0:16:35.56) |
Ruri Tanigawa : Does this rock sometimes
have a slick surface? |
(0:16:36.64) |
|
Youko Imari : Yeah, it's called slickenside. |
(0:16:39.45) |
Youko Imari : Slickensides form when serpentinite surfaces
rub against each other and cause friction. |
(0:16:41.96) |
|
Ruri Tanigawa : I might have found that! |
(0:16:45.22) |
|
Nagi Arato : Do you have it on you? |
(0:16:46.43) |
|
Ruri Tanigawa : I put it back. |
(0:16:48.07) |
Nagi Arato : Either way, we'll need to check
where the serpentinite came from. |
(0:16:51.87) |
|
Youko Imari : Yup. |
(0:16:55.33) |
|
Ruri Tanigawa : Serpentinite, serpentinite... |
(0:16:59.35) |
Nagi Arato : Ruri, we won't be looking
in the river today. |
(0:17:01.19) |
Nagi Arato : Platinum can only be supplied
by a large amount of serpentinite. |
(0:17:04.42) |
Nagi Arato : We'll search directly for the source
in the mountains today. |
(0:17:09.02) |
|
Ruri Tanigawa : Hey, why is there platinum in serpentinite? |
(0:17:14.52) |
Nagi Arato : That's because serpentinite is an ore rock
that originates from the Earth's mantle. |
(0:17:19.23) |
|
Nagi Arato : Compared to the crust, the mantle contains |
(0:17:24.73) |
Nagi Arato : higher concentrations
of rare metals, like platinum. |
(0:17:27.34) |
|
Ruri Tanigawa : Meaning the mantle's a treasure trove! |
(0:17:29.97) |
Youko Imari : To save our strength for the
treasure trove, can we take a break? |
(0:17:33.70) |
|
Ruri Tanigawa : You can do it! You can do it! |
(0:17:36.39) |
Ruri Tanigawa : Do rocks from the mantle
exist all over the place? |
(0:17:38.92) |
Nagi Arato : Nope. Normally, mantle materials
don't reach the Earth's surface. |
(0:17:41.41) |
|
Ruri Tanigawa : So you can only find it in special places? |
(0:17:45.69) |
|
Nagi Arato : That's right. |
(0:17:47.71) |
Nagi Arato : For instance, at continental
plate boundaries, |
(0:17:49.07) |
Nagi Arato : rock masses that are dozens of
kilometers thick compress, |
(0:17:51.58) |
|
Nagi Arato : causing one plate to thrust over the other. |
(0:17:55.36) |
|
Nagi Arato : This can expose the mantle rocks at the surface. |
(0:17:58.12) |
|
Ruri Tanigawa : That's nature on a giant scale. |
(0:18:00.32) |
Nagi Arato : An actual example of this
is Hokkaido's Hidaka Mountains. |
(0:18:02.83) |
|
Ruri Tanigawa : You were talking about Japan? |
(0:18:05.92) |
Nagi Arato : Serpentinite can be found
in the central Pacific ridge. |
(0:18:08.05) |
Nagi Arato : It's an area where eruptions
include mantle materials. |
(0:18:11.85) |
Nagi Arato : Serpentinite is carried by plates and
eventually becomes sediment beneath Japan. |
(0:18:15.13) |
Nagi Arato : This serpentinite sometimes
appears above the Earth's surface. |
(0:18:20.41) |
|
Ruri Tanigawa : Above the surface? |
(0:18:23.86) |
Nagi Arato : For example, serpentinite can
rise to the surface through faults. |
(0:18:25.40) |
|
Ruri Tanigawa : You say that like you saw it happen. |
(0:18:29.50) |
|
Ruri Tanigawa : How can you tell all that? |
(0:18:32.20) |
Nagi Arato : You're right. No one's ever seen
the upper layer of serpentinite. |
(0:18:34.31) |
Nagi Arato : But if you learn about rocks and terrain,
you can piece together information. |
(0:18:38.17) |
|
Nagi Arato : Ready? I'll pull you up. |
(0:18:45.40) |
|
Ruri Tanigawa : Thanks. |
(0:18:47.57) |
|
Ruri Tanigawa : Nagi-san! |
(0:18:54.90) |
|
Ruri Tanigawa : There's a weird black chunk. |
(0:18:56.03) |
|
Nagi Arato : It's a serpentine block. Just as I thought. |
(0:19:00.49) |
|
Ruri Tanigawa : This is it? Part of the mantle? |
(0:19:03.90) |
|
Ruri Tanigawa : If it rises to the surface from underground, |
(0:19:07.86) |
|
Ruri Tanigawa : is it like the volcanic eruptions we see on TV? |
(0:19:09.71) |
|
Nagi Arato : Serpentine can't melt into lava, |
(0:19:13.72) |
Nagi Arato : but it may still be linked to natural
phenomena like volcanic eruptions. |
(0:19:17.41) |
|
Ruri Tanigawa : It all sounds so grand and surreal. |
(0:19:21.42) |
Ruri Tanigawa : I can hardly imagine it
from these quiet mountains. |
(0:19:23.73) |
|
Nagi Arato : Whether it's volcanoes or rocks, |
(0:19:27.74) |
Nagi Arato : we only get to see a tiny sliver
of its entire lifecycle. |
(0:19:29.26) |
|
Nagi Arato : When volcanoes erupt, they spew tons of lava |
(0:19:32.23) |
Nagi Arato : and send plumes of ash
thousands of meters into the sky. |
(0:19:34.22) |
Nagi Arato : It's a captivating sight, but that's
only part of the eruption process. |
(0:19:37.95) |
Nagi Arato : Beneath volcanoes, there are
boiling magma chambers. |
(0:19:44.33) |
Nagi Arato : Magma upwelling delivers massive
amounts of energy from the mantle. |
(0:19:46.95) |
Nagi Arato : This energy pierces through
the Earth's surface. |
(0:19:51.90) |
Nagi Arato : That's a brief overview
of volcanic eruptions. |
(0:19:55.44) |
Nagi Arato : The eruption itself is just
one part of the whole process. |
(0:19:58.40) |
|
Nagi Arato : Same goes for the serpentinite here. |
(0:20:01.93) |
Nagi Arato : This is just the tip of a massive
rock mass protruding above ground. |
(0:20:06.19) |
Nagi Arato : It took millions of years to reach here
after breaking off from the mantle. |
(0:20:10.86) |
|
Nagi Arato : Volcanoes, serpentinite, placer platinum... |
(0:20:18.16) |
Nagi Arato : We need to learn about the unseen
if we want to know their whole truth. |
(0:20:20.62) |
|
Ruri Tanigawa : So we need to see the unseen... |
(0:20:26.04) |
|
Nagi Arato : Well. That finally settles the debate. |
(0:20:33.38) |
|
Nagi Arato : Ready to go find what we've uncovered? |
(0:20:37.72) |
|
Ruri Tanigawa : Found one! Placer platinum! |
(0:20:41.90) |
|
Nagi Arato : You're a natural. |
(0:20:44.22) |
|
Ruri Tanigawa : I've gotten used to spotting tiny grains. |
(0:20:45.69) |
Ruri Tanigawa : Imari-san, you still have
a lot of sand to sift through. |
(0:20:48.16) |
|
Youko Imari : Well, it is
my first time panning. |
(0:20:51.12) |
Nagi Arato : I found one too. I didn't
expect there to be so much. |
(0:20:54.95) |
|
Ruri Tanigawa : Lemme see! |
(0:20:57.75) |
|
Youko Imari : How are you finding them? |
(0:20:59.28) |
|
Ruri Tanigawa : Yeah, just like that. |
(0:21:03.78) |
|
Youko Imari : Like this? |
(0:21:05.91) |
|
Nagi Arato : Hey you two, come over here. |
(0:21:06.57) |
Nagi Arato : There's some sand
accumulated in this crevice. |
(0:21:09.67) |
|
Ruri Tanigawa : Imari-san, let's go! |
(0:21:13.47) |
|
Nagi Arato : I never thought we'd find placer platinum here. |
(0:21:41.84) |
|
Ruri Tanigawa : It's all thanks to my search for sapphire! |
(0:21:44.91) |
|
Youko Imari : I can't believe we found this much. |
(0:21:48.25) |
|
Ruri Tanigawa : Still! |
(0:21:50.75) |
|
Ruri Tanigawa : It's only the little bit we can see. |
(0:21:52.63) |
|
Ruri Tanigawa : There's a ton more out there, right? |
(0:21:54.52) |
