Short Wave

Zircon: The Keeper Of Earth's Time

Jan 10, 2023

Nell Greenfieldboyce, an NPR science correspondent specializing in geology, dives into the fascinating world of zircon, the planet's oldest known mineral. She reveals that these resilient crystals date back 4.37 billion years, serving as geologic clocks that mark significant events in Earth's history. The discussion highlights how advancements in zircon research are unlocking secrets about early cosmic events, like the Moon's formation, as well as improvements in dating techniques using uranium decay. Zircon's durability makes it essential for understanding our planet's ancient past.

11:58

Creator website

Episode guests

Nell Greenfieldboyce

AI Chapters

Episode notes

Intro

2min

Exploring the Ancient History of Zircons

2min

The Resilient History of Zircons in Earth's Geology

2min

Zircons and Uranium: Unveiling Earth's History

5min

Exploring the Endless Quest for Zircon Insights

2min

The mineral zircon is the oldest known piece of Earth existing on the surface today. The oldest bits date back as far as 4.37 billion years — not too far from the age of Earth itself at about 4.5 billion years old. And, unlike other minerals, zircon is hard to get rid of. This resilience enables scientists to use zircon to determine when major geological events on Earth happened. As part of our series on time, host Aaron Scott talks to science correspondent Nell Greenfieldboyce about why this mineral is often considered a geologic clock and has earned the nickname "Time Lord."

This episode is part of our series, "Finding Time — a journey through the fourth dimension to learn what makes us tick." Read more of Nell's reporting on zircon here.

Curious about other aspects of our universe? Email us at ShortWave@NPR.org.

Learn more about sponsor message choices: podcastchoices.com/adchoices

NPR Privacy Policy

Remember Everything You Learn from Podcasts

Save insights instantly, chat with episodes, and build lasting knowledge - all powered by AI.