The 3 standard crystals are Red, Green, Blue, we can get those easily from missions. The issue is BW decided to make two restricted to light side, and one for dark side. That means every time I do an Archeology mission, I have the chance to get 2 crystal types that are in very low demand, and one that I cannot keep up with.
My bank has almost 100 of each green and blue; and zero red.
The missions either needs to be color specific, or give us a mechanism to change the crystal's color.