Breaking Geodes

June 05, 2019



Photographer: Stu Witmer
Summary Authors: Jace Jammerman, Stu Witmer

Geodes are super-cool rocks with crystals inside. Each one is different. Plain and dull-looking outside, many are breathtakingly beautiful inside. A few geodes are solid. These are sometimes called nodules. Most are hollow and filled with inward-pointing crystals. Generally, these crystals are quartz but can be a variety of other minerals. There's only one way to tell what's inside: break it open. Geodes can range in size from that of a walnut to several feet in diameter. Most are about fist-sized. These are also the easiest to open. To open a geode, wrap it in a couple of old socks or a thick cloth then whack it with a hammer. Be sure to wear eye protection because bits of rock may fly all over the place even if the geode is wrapped securely. Geodes (Greek for earthlike) can be found in many locations, including sedimentary limestone and basaltic lavas, weathered out of cliffs, or scattered about in talus. They can also be purchased in rock shops, some toy stores and online. Top image shows two geodes before breaking, bottom is after.