Indeed, Nethocite is the key here. The Sun-Cryst plays a huge role in unravleing what started everything and by the end of the Pharos, you'll catch a glimpse of that.

The Sun-Cryst is probably the most important and coveted source which (produces?) the deifacted nethicite. The Occuria whore over it, as well as the main baddies in the game which I'm sure those of you who have played enough into, will know who I am referring to without giving it away for the rest.