Cleaning & Cracking Géodes, Great and Small

Geodes. From their Latin and Greek origins meaning ‘earth-like,’ the cracking and cleaning of these popular stone eggs is no yolk: those unassuming exteriors can belie wonderful clusters of crystals or banded layers of agate within!

- BY L.A. BERRY

Agate and quartz lining a geode (Cleveland Museum of Natural History, Ohio).

Creative Commons/Wikipedia

That prize-winning feeling from cracking open a geode to reveal the treasures within segues into a fun and educational introduction to geology. Plus, geode cracking has an enthusiastic following on social media, where the satisfying “Pop!” sound that comes from opening a geode is described as stimulating a relaxing and enjoyable ASMR (Autonomous Sensory Meridian Response).

“The first geodes I cracked open were sent by a subscriber to my YouTube channel, which turned into a good friendship, big thanks @GeodeCrackerCollector,” says a Minnesota geode collector (Taylor) who goes by @AgateDad. “I'm late to the cracking game. I was in my late twenties when I cracked those. Geodes are my second favorite mineral. Agates are first.” He has 188,000 subscribers happy to watch him open everything from Oregon thunder eggs to agatized corals.

GEODE VS. AGATE?

What’s the difference between a geode and an agate? In short, a geode is a hollow rock, with a crystal-lined cavity inside, found mostly in basaltic lavas or limestone. Agates are solid, usually banded, stones formed from accumulated layers of silica inside volcanic or sedimentary rock cavities. Agate (or opal) also composes the solid, often star-shaped core of another popular collectible, geodal thunder eggs.

POP GOES THE GEODE

Agate Dad, Taylor with geodes in his workroom.