User blog comment:Tellecron/What if Salem used a combination of Dust to become a Grimm or Grimm Like Creature/@comment-26397825-20171029102138

I've always thought the crystals in her domain to be Gravity Dust, which we know is purple/black. In fact, in V5 Ep 2 we see black crystals which are holding up the floating islands Weiss and the Pilot are making their way through, which ha sbeen confirmed in RWBY Rewid to be Gravity Dust.