WEBVTT - Why Are There Diamonds in the Ocean? 0:00:01.920 --> 0:00:06.320 Welcome to brain Stuff, a production of iHeart Radio. Hey 0:00:06.400 --> 0:00:10.040 brain Stuff, Lauren Bogabam Here. If you've ever heard the 0:00:10.039 --> 0:00:14.280 slogan a diamond is Forever, then a nineteen forties marketing 0:00:14.320 --> 0:00:17.919 campaign is still doing its job. The line was coined 0:00:17.920 --> 0:00:20.239 by an ad woman working with the agency that was 0:00:20.280 --> 0:00:23.600 with de Beers Group. They're the company credited with almost 0:00:23.680 --> 0:00:27.200 single handedly popularizing diamonds and engagement rings from the late 0:00:27.280 --> 0:00:31.160 nineteen forties onwards. Yep, that trend isn't even a century old. 0:00:32.800 --> 0:00:36.199 De Beers spent decades building a global empire, and some 0:00:36.240 --> 0:00:39.159 would call it a cartel around diamond mines that they 0:00:39.240 --> 0:00:43.839 owned in countries like South Africa. So why did they 0:00:43.920 --> 0:00:47.080 purchase more than three thousand square miles and that's about 0:00:47.159 --> 0:00:50.320 seven thousand, eight hundred square kilometers of Atlantic seafloor near 0:00:50.360 --> 0:00:55.400 the coast of Namibia. It's simple. Not all diamonds are 0:00:55.400 --> 0:00:58.480 found on dry land. Many turn up and sediments below 0:00:58.480 --> 0:01:01.120 the ocean's surface. You just have to know where to look. 0:01:02.760 --> 0:01:07.280 Carbon is a wonderfully versatile element found in Earth's crust, atmosphere, 0:01:07.400 --> 0:01:10.520 and all living things that we know of anyway. It's 0:01:10.600 --> 0:01:14.560 also well represented in jewelry stores. Diamonds are made of 0:01:14.560 --> 0:01:17.800 carbon atoms that have been subjected to extremely high temperatures 0:01:17.800 --> 0:01:21.720 and pressures. The crystals usually have eight sides before being cut, 0:01:21.880 --> 0:01:24.399 but six and twelve sided specimens are out there too. 0:01:25.800 --> 0:01:29.440 Inside a diamond, every individual carbon atom shares a strong 0:01:29.520 --> 0:01:34.319 bond with four others, which makes diamonds ridiculously hard. Rub 0:01:34.360 --> 0:01:37.280 one of these gems against almost any other known material 0:01:37.480 --> 0:01:41.800 and it'll leave a scratch mark behind. Asteroids can create 0:01:41.800 --> 0:01:44.240 the intense heat and pressure needed to produce diamonds when 0:01:44.280 --> 0:01:47.560 they strike the face of our planet. Such impact diamonds 0:01:47.560 --> 0:01:49.800 are pretty rare, though, and they tend to be small. 0:01:51.080 --> 0:01:53.360 You're way more likely to find a diamond from deep 0:01:53.440 --> 0:01:56.960 within the Earth, forged somewhere in the ballpark of five 0:01:57.040 --> 0:02:00.320 hundred miles under the surface. That's around a hundred forty 0:02:00.840 --> 0:02:05.000 d kilometers, and the ocean may have played an underappreciated 0:02:05.120 --> 0:02:07.840 role in the history of our world's diamonds supply as well. 0:02:09.320 --> 0:02:13.960 Many diamonds contain small quantities of salt. For years, geologists 0:02:13.960 --> 0:02:18.359 wondered if this originally came from sea water. A study 0:02:18.400 --> 0:02:21.679 published in the journal Science Advances in twenty nineteen bolstered 0:02:21.760 --> 0:02:24.720 this hypothesis. It turns out that when a blend of 0:02:24.760 --> 0:02:29.040 marine sediments and the volcanic rock peridotite experience high heat 0:02:29.080 --> 0:02:32.440 and tremendous pressure in a laboratory setting, you get something 0:02:32.480 --> 0:02:35.399 that looks an awful lot like the salts trapped inside 0:02:35.400 --> 0:02:39.760 some diamonds. What's this mean for the real world, though, 0:02:40.240 --> 0:02:43.280 According to the papers authors, their experiment suggests that most 0:02:43.360 --> 0:02:46.600 diamonds come into being after chunks of seafloor are dragged 0:02:46.600 --> 0:02:50.760 into Earth's mantle via plate tectonics, and some of the 0:02:50.800 --> 0:02:54.400 minerals taken from the ocean during this process crystallize into gems. 0:02:55.040 --> 0:02:57.800 Volcanic eruptions later bring the diamonds up to the planet's 0:02:57.800 --> 0:03:01.519 surface or pretty close to it. And now, the study 0:03:01.520 --> 0:03:04.800 mentioned above doesn't explain whide Biers and other groups are 0:03:04.880 --> 0:03:08.560 hunting for diamonds off the African coast, those stones who 0:03:08.600 --> 0:03:11.240 are more likely carried out to sea by river currents. 0:03:11.840 --> 0:03:15.079 Namibia's southern border is defined by the Mighty Orange River. 0:03:15.600 --> 0:03:17.920 For millions of years, it's been grabbing a hold of 0:03:17.960 --> 0:03:21.679 diamonds from mainland deposits and relocating them elsewhere on the continent. 0:03:22.919 --> 0:03:26.079 Only sometimes this river ferries the stones all the way 0:03:26.080 --> 0:03:30.480 out to the ocean. Since the nineteen sixties, treasure seekers 0:03:30.520 --> 0:03:32.680 have been dredging up diamonds by the coast lines of 0:03:32.720 --> 0:03:37.360 northwestern South Africa and southern Namibia. In twenty eighteen, nearly 0:03:37.400 --> 0:03:40.320 seventy five percent of the latter countries total diamond output 0:03:40.440 --> 0:03:44.720 came from ocean based mining operations. Most of these gems 0:03:44.720 --> 0:03:47.240 are harvested at depths of four hundred two four hundred 0:03:47.280 --> 0:03:49.120 and fifty feet that's about a hundred and twenty two 0:03:49.200 --> 0:03:53.120 hundred and forty meters below sea level. To accomplish this, 0:03:53.480 --> 0:03:55.920 sediments from the ocean floor are sucked up into a 0:03:56.000 --> 0:03:59.400 remote controlled crawler vehicle that scuttles across the sea bed. 0:04:00.080 --> 0:04:03.360 Fitted with mechanical arm it sends diamond ladden payloads to 0:04:03.360 --> 0:04:06.720 the main vessel up above, where machines separate out the crystals. 0:04:08.160 --> 0:04:10.800 Drones and two person submarines have both been used to 0:04:10.840 --> 0:04:15.960 help these ships find diamond rich areas beneath the waves. Unfortunately, though, 0:04:16.120 --> 0:04:20.120 dredging campaigns can have long term consequences for aquatic wildlife. 0:04:21.000 --> 0:04:25.359 As a cologist Kirsten Thompson told CNN, in the waters 0:04:25.440 --> 0:04:27.919 off the coast of Namibia are an important area for 0:04:27.960 --> 0:04:32.800 a high diversity of resident and migratory species such as sharks, whales, dolphins, 0:04:32.800 --> 0:04:36.039 and seals. Marine mining removes part of the seabed with 0:04:36.160 --> 0:04:39.400 heavy machinery and habitat. Recovery from this type of disturbance 0:04:39.560 --> 0:04:44.840 can take decades. Gathering these ocean diamonds by hand with 0:04:44.960 --> 0:04:48.000 higher divers in small boats is another option that's been 0:04:48.000 --> 0:04:56.200 executed in recent years. Today's episode is based on the 0:04:56.279 --> 0:04:58.680 article are there Diamonds in the Ocean on how stuff 0:04:58.680 --> 0:05:01.720 works dot com written by mar Mancini. Brain Stuff is 0:05:01.760 --> 0:05:03.960 production of I heart Radio in partnership with how stuffworks 0:05:03.960 --> 0:05:06.480 dot Com, and it's produced by Tyler Klang. For more 0:05:06.520 --> 0:05:09.160 podcasts my heart Radio, visit the i heart Radio app, 0:05:09.240 --> 0:05:11.880 Apple Podcasts, or wherever you listen to your favorite shows.