Board Thread:General Discussion/@comment-24901923-20151016044237/@comment-26023629-20151025024454

I'd just like to point out, if it hasn't been already, that the common varieties of quartz line up pretty well with the team. Citrine is yellow (Taiyang), Smoky Quartz is gray-black (Qrow/Raven), and Milky Quartz is white (Summer).

Plus, a well-know variety of quartz is Rose Quartz. Pretty obvious association there.