Petty John's Cave popular destinations of the cave. Formations in Petty John's Cave include: Stalagmites that are a type of speleothem that rises from the floor of a limestone cave due to the dripping of mineralized solutions and the deposition of calcium carbonate. Stalactites are also found in the cave. These formations hang from the ceiling or wall of the cave. There are also pillars, soda straws, cave pearls, flowstones, and cave popcorn are other formations in the cave. In addition, waterfalls can be found in the stream passage section. This cave hosts tri-colored bats during their winter hibernation because temperatures are low
Cave of the Crystals deposits of silver, zinc and lead. The Cave of Crystals is a horseshoe-shaped cavity in limestone. Its floor is covered with perfectly faceted crystalline blocks. Huge crystal beams jut out from both the blocks and the floor. The crystals deteriorate in air, so the Naica Project attempted to visually document the crystals before they deteriorate further. Two other smaller caverns were also discovered in 2000, Queen’s Eye Cave and Candles Cave, and a further chamber was found in a drilling project in 2009. The new cave, named Ice Palace, is deep and is not flooded, but its crystal formations are