Speaker 1: Welcome to brain Stuff, a production of iHeart Radio. Hey
Speaker 1: brain Stuff, Lauren Bogabam Here. If you've ever heard the
Speaker 1: slogan a diamond is Forever, then a nineteen forties marketing
Speaker 1: campaign is still doing its job. The line was coined
Speaker 1: by an ad woman working with the agency that was
Speaker 1: with de Beers Group. They're the company credited with almost
Speaker 1: single handedly popularizing diamonds and engagement rings from the late
Speaker 1: nineteen forties onwards. Yep, that trend isn't even a century old.
Speaker 1: De Beers spent decades building a global empire, and some
Speaker 1: would call it a cartel around diamond mines that they
Speaker 1: owned in countries like South Africa. So why did they
Speaker 1: purchase more than three thousand square miles and that's about
Speaker 1: seven thousand, eight hundred square kilometers of Atlantic seafloor near
Speaker 1: the coast of Namibia. It's simple. Not all diamonds are
Speaker 1: found on dry land. Many turn up and sediments below
Speaker 1: the ocean's surface. You just have to know where to look.
Speaker 1: Carbon is a wonderfully versatile element found in Earth's crust, atmosphere,
Speaker 1: and all living things that we know of anyway. It's
Speaker 1: also well represented in jewelry stores. Diamonds are made of
Speaker 1: carbon atoms that have been subjected to extremely high temperatures
Speaker 1: and pressures. The crystals usually have eight sides before being cut,
Speaker 1: but six and twelve sided specimens are out there too.
Speaker 1: Inside a diamond, every individual carbon atom shares a strong
Speaker 1: bond with four others, which makes diamonds ridiculously hard. Rub
Speaker 1: one of these gems against almost any other known material
Speaker 1: and it'll leave a scratch mark behind. Asteroids can create
Speaker 1: the intense heat and pressure needed to produce diamonds when
Speaker 1: they strike the face of our planet. Such impact diamonds
Speaker 1: are pretty rare, though, and they tend to be small.
Speaker 1: You're way more likely to find a diamond from deep
Speaker 1: within the Earth, forged somewhere in the ballpark of five
Speaker 1: hundred miles under the surface. That's around a hundred forty
Speaker 1: d kilometers, and the ocean may have played an underappreciated
Speaker 1: role in the history of our world's diamonds supply as well.
Speaker 1: Many diamonds contain small quantities of salt. For years, geologists
Speaker 1: wondered if this originally came from sea water. A study
Speaker 1: published in the journal Science Advances in twenty nineteen bolstered
Speaker 1: this hypothesis. It turns out that when a blend of
Speaker 1: marine sediments and the volcanic rock peridotite experience high heat
Speaker 1: and tremendous pressure in a laboratory setting, you get something
Speaker 1: that looks an awful lot like the salts trapped inside
Speaker 1: some diamonds. What's this mean for the real world, though,
Speaker 1: According to the papers authors, their experiment suggests that most
Speaker 1: diamonds come into being after chunks of seafloor are dragged
Speaker 1: into Earth's mantle via plate tectonics, and some of the
Speaker 1: minerals taken from the ocean during this process crystallize into gems.
Speaker 1: Volcanic eruptions later bring the diamonds up to the planet's
Speaker 1: surface or pretty close to it. And now, the study
Speaker 1: mentioned above doesn't explain whide Biers and other groups are
Speaker 1: hunting for diamonds off the African coast, those stones who
Speaker 1: are more likely carried out to sea by river currents.
Speaker 1: Namibia's southern border is defined by the Mighty Orange River.
Speaker 1: For millions of years, it's been grabbing a hold of
Speaker 1: diamonds from mainland deposits and relocating them elsewhere on the continent.
Speaker 1: Only sometimes this river ferries the stones all the way
Speaker 1: out to the ocean. Since the nineteen sixties, treasure seekers
Speaker 1: have been dredging up diamonds by the coast lines of
Speaker 1: northwestern South Africa and southern Namibia. In twenty eighteen, nearly
Speaker 1: seventy five percent of the latter countries total diamond output
Speaker 1: came from ocean based mining operations. Most of these gems
Speaker 1: are harvested at depths of four hundred two four hundred
Speaker 1: and fifty feet that's about a hundred and twenty two
Speaker 1: hundred and forty meters below sea level. To accomplish this,
Speaker 1: sediments from the ocean floor are sucked up into a
Speaker 1: remote controlled crawler vehicle that scuttles across the sea bed.
Speaker 1: Fitted with mechanical arm it sends diamond ladden payloads to
Speaker 1: the main vessel up above, where machines separate out the crystals.
Speaker 1: Drones and two person submarines have both been used to
Speaker 1: help these ships find diamond rich areas beneath the waves. Unfortunately, though,
Speaker 1: dredging campaigns can have long term consequences for aquatic wildlife.
Speaker 1: As a cologist Kirsten Thompson told CNN, in the waters
Speaker 1: off the coast of Namibia are an important area for
Speaker 1: a high diversity of resident and migratory species such as sharks, whales, dolphins,
Speaker 1: and seals. Marine mining removes part of the seabed with
Speaker 1: heavy machinery and habitat. Recovery from this type of disturbance
Speaker 1: can take decades. Gathering these ocean diamonds by hand with
Speaker 1: higher divers in small boats is another option that's been
Speaker 1: executed in recent years. Today's episode is based on the
Speaker 1: article are there Diamonds in the Ocean on how stuff
Speaker 1: works dot com written by mar Mancini. Brain Stuff is
Speaker 1: production of I heart Radio in partnership with how stuffworks
Speaker 1: dot Com, and it's produced by Tyler Klang. For more
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