"There's an interesting cave in Argengisian Empire near the border of the Grand Duchy. It's a beautiful cavern but wear some heavy soled boots. Those crystals will tear up your footwear. Its worth it though because those crystals are easily hundreds of gold." ~ Unknown Pathfinder
Inside the cavern there are very few creatures that claim this cavern as home. Bulettes will occasionally make their way into the cavern and consume of the the crystals before returning to the surface below.
The entirety of the Crystal Caverns is an amalgamation of different types of crystals. Diamond, quartz, onyx, emerald; the list goes on. Many speculate how the cavern came into existence. There are two reigning theories about what caused this phenomena. Firstly, there's a possibility that the cavern was a result of the after effects of the Divine War. This theory is less likely since many religious scholars predict that the crystals would have some type of divine residue inside them but none, currently, present themselves as divine. The second theory is that this cavern belonged to a red dragon. Some arcanist believe that the prolonged exposure to the intense heat and possible pressure of given off by the dragon caused these crystals to form. Though why there are different gems and crystals formed in this cavern is a mystery but could also be explained that the dragon was hording them and caused them to grow magically.
The cavern is seems to be able to produce any type of crystal or gem that can be found on Aedran.
The Crystal Caverns is currently under the control of the Drugor Mining company. Though progress is slow the mining is profitable. Though the current operations are on pause since a new part of the cavern was discovered and the Pathfinders have no finished the exploration of this new system.