Discovery, Scientific
The humans discover a method that allows selenite to be "programmed" and controllable, providing use for things outside of religious monoliths or power sources.
While researching selenite's origins and abilities, the humans eventually developed a way to "program" selenite into executing specific functions without relying on the crystal's natural unpredictability. This is completed through infusing the crystals with mana and a hex along with the intent and willpower of whatever outcome the programmer wants to ensure from it.