Geodes, crystals bursting out of a rocky shell ... and tiny crystal layers form inside the rock-bubble. As layers upon layers of mineral-water-turned-crystals form over thousands or millions ...

On a recent two-day trip seeking Iowa history, Marion and Rich Patterson discovered that Keokuk is much like its abundant ...

Discovered in 1999 inside an abandoned mine in Southern Spain, Pulpí Geode is the largest crystal 'cave' of its kind in the world. But what exactly is a geode and how do crystals form inside them?

Large crystals found in geodes and other rocks are relatively rare. Pink ChalcedonyA pink chalcedony shows off its beauty. Chalcedonies include many types of cryptocrystalline quartz gems and ...

Geodes are hollow rock formations often with quartz crystals, such as amethyst, inside. Amethyst geodes in Uruguay have been found in cooled lava flows, which date from the original breakup of the ...