User blog comment:Icchi/Let's talk about Dust (and Aura) part 2/@comment-20935641-20130828120457/@comment-20935641-20130828120959

As for the color of Aura and such, Aura is an extention of one's soul, so their soul energy is what they are, the color is just what the soul is as it's energy. It is the color it represents to represent the person it belongs to. As for Dust itself, The color represents the force it is infused with.