Show Notes
✨ The Weirdest Critical Metal You've Never Heard Of: Indium, Mine Waste & the Hunt for Hidden SuppliesYou've touched it hundreds of times. It's in your phone screen, your laptop, your solar panels, your TV. But unless you're a obsessed with periodic table trivia, you probably have no idea what it is.Meet indium. Its a critical metal so rare, yet so essential. But here's the catch: there's basically no such thing as an indium mine.Today we're talking to the wonderful Dr Olivia Mejas-Gonzales, a research fellow at the Centre in Critical Resources for the Future, who did her entire PhD on this obscure element. Olivia - you're going to love her. She's a dynamic Chilean and a curious scientist who's not afraid of getting her hands dirty. Olivia shares some of her experience working underground at El Teniente, one of the world's great copper mines; including the challenges she faced - and overcame - being the only female on site at the time. Amazing!And Indium? Well for Olivia that story involves mine waste, surprising mineral discoveries, mysterious supergene enrichment zones, and some super cool synchrotron research. Plus, she's got a teaser about using biology to extract critical metals from waste rock. Trust us, you'll want to hear more.🎯 This episode:🌍 Why indium is critical (answer: every screen you own)💻 The supply chain paradox: we need it desperately, we barely mine it🪨 Why indium is almost nothing in the Earth's crust⛏️ How indium hides as a byproduct of zinc extraction, mostly in China🔬 Olivia's PhD adventure: finding indium in mine waste environments🪣 Supergene enrichment: when waste rock dumps hide geological surprises🔄 The living angle: can organisms dissolve and extract critical metals?🧪 Synchrotron science and the power of asking unconventional questionsAnd one of the standout quotes from Olivia:"I'm just curious without fear to fail. It doesn't matter if I fail because I know I will try again."Kinda one of the standout quotes from our whole Wonder series to be real!🔗 Find us:📺 @theGeoCo on YouTube📻 Wonder on Spotify🐦 @theGeoCo on TikTok📸 @theGeoCo on Instagram📬 Geoco News on Substack: thegeoco.substack.comThis episode was produced in partnership with the ARC Training Centre in Critical Resources, which brings together industry, four of Australia's leading universities, and state and federal governments to address the challenge of securing our future resources.🙏 We acknowledge the Kaurna people of the Adelaide Plains, on whose country the Wonder podcast is made.Thank you to Podbooth studios, Adelaide where we record our podcast.— Holly and Anthony
More from Wonder
Where Anthony sees crystals and Holly sees a rock, Dr Eric Vandenberg sees atoms, and specifically, Eric counts the neutrons. Eric is a postdoc at the Adelaide University and part of the ARC Training Centre for Critical Resources for the Future, and he shrinks the solid Earth down to the subatomic scale to answer some of geology's biggest questions: how the first continents formed, how plate tectonics got started, and how the rarest metal deposits on the planet came to be. ⚛️ What even is an isotope? Same element, different number of neutrons. But some isotopes are "radiogenic" and quietly decay over geological time (hello, beta and alpha decay), and why anything heavier than lead is inherently unstable. ⏳ The gold standard for dating rocks: why uranium and thorium love hiding inside zircon crystals, why lead doesn't, and how that mismatch lets geologists measure the exact age of a rock - this is geochronology in a nutshell. 🪨 The Pilbara: older than almost anything left on Earth. A craton stretching from 3.6 to 2.8 billion years old, closer in age to the formation of the planet than to today, and one of the best-preserved windows we have into Earth's earliest crust. 🌋 Earth vs Venus: why Earth is the only planet in the solar system with true plate tectonics, what a "stagnant lid" planet like Venus looks like instead, and the decades-old scientific debate over exactly when Earth made the switch. ⛏️ From ancient cratons to critical minerals: How isotope geochemistry traces the journey of gold, copper, nickel and platinum from sulfides deep in the mantle into the porphyry and IOCG deposits we mine today, without needing the impossibly hot magmas of the early Earth. A huge thank you to the Centre for Critical Resources for the Future for supporting this episode. 🔗 Find us at thegeoco.com.au 📸 Instagram & TikTok: @thegeoco 📰 Sign up to our newsletter: thegeoco.substack.com GeoCo connects to you from the traditional country of the Kaurna people of the Adelaide Plains, South Australia. We pay our respects to their Elders past, present, and emerging.
Volcanologist Dr Hayden Dalton (University of Melbourne) joins Holly & Anthony with the science he's bringing to a fascinating human question: exactly how many hominin species were alive at the same time, in the same place, and were they really competing for the same resources? Or... has the apparent overlap in existing timelines been an artifact of imprecise dating? Hayden reveals that scientists can now bracket ash layers to within about 800 years on rocks over a million years old, roughly a tenfold jump in precision from a couple of decades ago, and that new resolution is what makes it possible to test whether the overlap theory holds up (or not!). What an epic leap in science tech?!! Hayden walks us through the mystery of ancient 'trackways', that at over a million years old, preserves two different hominins' footprints in the same ash - proof, at least in that moment, that more than one species walked the same ground... You'll have to listen to find out what Hayden's age-dating reveals.Lastly, we pivot 360 to to Hayden's first volcanic love - kimberlites... Make sure you're following Wonder wherever you get your podcasts - and chuck that notifications bell on! Find us on Instagram @thegeoco Thanks to the Geological Society of Australia for making this episode of Wonder possible! GeoCo comes to you from the traditional country of the Kaurna people of the Adelaide Plains, South Australia. We pay our respects to their Elders past, present, and emerging.
Pushing the frontiers of knowledge about our planet has never been so much fun! We've explored less of the ocean floor than we have the surface of Mars, so Dr Ron Hackney, director of ANZIC (the Australian New Zealand International Scientific Drilling Consortium), brought the ocean floor to us. Across three remarkable objects: a core from the fault that ruptured the 2011 Tōhoku earthquake; a set of microscopic radiolarian fossils; and the world-famous "day the dinosaurs died" core from the Gulf of Mexico; we trace what scientific ocean drilling can tell us about earthquakes, mass extinction, and life clinging on kilometres beneath the seafloor. We also hear how Ron went from an Antarctica-obsessed undergraduate to leading Australia and New Zealand's role in international ocean drilling. Thanks to the Geological Society of Australia for facilitating this episode, and so many Wonder episodes over the past couple of years.🔗 Find us at thegeoco.com.au 📸 Instagram & TikTok: @thegeoco 📰 Sign up to our newsletter: thegeoco.substack.comGeoCo connects to you from the traditional country of the Kaurna people of the Adelaide Plains, South Australia. We pay our respects to their Elders past, present, and emerging.
We've directly observed less than 0.001% of the seafloor — so what's really going on down there? In this episode, Dr Stefan Löhr (ARC Future Fellow at the Adelaide University, and researcher with the Centre for Critical Resources for the Future) makes the case that the ocean floor is anything but a passive dumping ground for eroded continents. This will reshape the way you view the ocean - who knew it was so dynamic! We trace marine weathering from a decades-old mystery in seawater chemistry, through the strange true nature of "clay" (and why geologists bite rocks to classify it), into the surprisingly unresolved question of whether land plants permanently changed how fast the Earth weathers. Finally we digress to discuss a rare earth element deposit in South Australia that shouldn't exist by the textbook rules, sitting on limestone that has essentially zero rare earths of its own. Turns out the answer is written in an ancient lagoon, a pH gradient, and a very long river. Supported by the ARC Centre for Critical Resources for the Future. 🔗 Find us at thegeoco.com.au📸 Instagram & TikTok: @thegeoco📰 Sign up to our newsletter: thegeoco.substack.com GeoCo connects to you from the traditional country of the Kaurna people of the Adelaide Plains, South Australia. We pay our respects to their Elders past, present, and emerging.
Critical Chromium: From Field Samples to Space Technology: How Do We Secure Supply?