The Cave of Crystals is an underground cavern filled with tree-size gypsum crystals, including some of the largest natural ...

Imagine a cave where the walls are covered with huge, sparkling crystals, some as big as trees. This isn’t a scene from a ...

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?

I would spend two nights recording the team’s progress in mapping new parts of the cave and collecting scientific data. Ice crystals populate Full Moon Hall. The chamber, 820 feet long ...

Tiny crystals sparkled across the walls ... It was Becca, dropping into the cave. Then came Hannah. Now there were three scientists working in the cave together. For a month, Marina and five ...