The key characteristic of an eleiox is not that they are from Quintessence, though their power is of that plane. All eleiox are borne of the Plane of Titanic Elements, though many can and do trace their bloodline to the Plane of Quintessence. There are an existent minority of eleiox who are born on the face of Consarcio to human, or elven, or dwarven parents.
These eleiox born across the four continents, the Shattered Isles, and the many more islands of the world are often found born in places historically tied to the elements. Following a tragic volcanic erruption, there is a small uptick of heliox, teriox, and magma eleiox in nearby villages. Coastal towns and cities tend to be more prone to having hydrox born, while zephiox tend to be more common in mountainous or stormy regions.