This is something I've been thinking about.

So, all the orange crystals covering the landscape in some zones are corrupted crystals (over-aspected with one element). Okay. There are normal crystal structures dotting the landscape as well. Crystals are condensed aether. The Black Shroud is said to have ridiculously high aether concentrations in it, tying in to the presence of the Elementals. So, why aren't there huge crystal structures in the Shroud? We get them in Mor Dhona, the Burning Wall, etc.