User blog comment:ChishioKunrin/My view on Dust (so far)/@comment-10380701-20140307031556

I'd say it's possible to blend Dust. In powder form only. This is demonstrated in episode 2 as well, when Ruby sneezed on the tri-colored dust cloud, resulting in an explosion of fire... that releases electricity and a buncha ice.

Since the mix was accidental, most likely it didn't blend completely to make a new property of Dust.

Purple Dust on the other hand... is how you do it right. The SDC may have a hand in making that. If that's the case, maybe White Dust is the combination of all the natural Dusts, maybe?

This may explain why Purple and White dust aren't sold. Just my two cents. Because Dust is fucking confusing.