On a visit to Tucson, relatives took me to a gem and mineral show where we saw a collection of geodes. Ordinary on the outside; beautiful on the inside. Will you please tell us how they are formed and ...

Hand holding a purple geode in a green garden - FotoHelin/Shutterstock This guide highlights accessible, legal locations where enthusiasts can safely hunt for geodes and geode-like formations and take ...

Sparkling hollows filled with lustrous crystals, dubbed geodes, are often perceived as small objects that can fit comfortably on a bookshelf. But some are more like gigantic cathedrals filled with a ...

Researchers from the University of Göttingen have investigated an intriguing geological phenomenon in Uruguay. These scientists are trying to uncover the mysteries behind the formation of amethyst ...

Amethyst geodes—some stretching 5 m long—dot the ancient lava flows of Uruguay’s Los Catalanes mining area. The geodes contain calcite, colorless quartz, and agate, another quartz mineral. Large ...

Geodes are irresistible. They fill display cases and museums everywhere. I’ve even got one on my desk at home: a smooth, brownish rock encasing milky lavender crystals. It’s hard to deny the allure of ...