Photo courtesy of Peter Jones - A Shot in the Dark Cave Photography.

This room is called the Pearlsian Gulf because of all the "cave pearls" located in the pools of water. These formations are called cave pearls for a good reason. Not only because they look like pearls, but because they were created in much the same way oysters create real pearls. Oysters deposit a mucus-like substance around a grain of sand that gets into their shell, which hardens into a layer of pearl. Over time, these hardened layers build up to form a pearl.

In the case of the cave pearls, as water dripped from the ceiling and splashed into a puddle, tiny amounts of calcium dissolved in the puddle water slowly built up around small fragments of rock. Over a long period of time, the accumulated layers of calcium created these smooth, round pearls.

It's amazing how water, rich with minerals, dripping from the ceiling of this deep cave, could create so many incredibly different and varied forms of crystals. Many of the crystal formations in this cave would not be possible anywhere else because the conditions down here are just perfect for this crystal nursery.

Let's head back up to the cave entrance, and to blue sky. On the way out we'll be talking about how these spectacular caves were first formed...