Hm? [He glances behind him, though not quite fast enough to see the Froslass shoot more snowflakes at the Dusknoir. Instead, he catches nothing but a sickly sweet expression from the little ghost girl. She wasn't doing a~ny~thiiing~]

Oh, yes! Crystal is part ice. Actually, her eggs are the only ones that won't hatch into a ghost. Snorunts are pure ice types, but they have two evolution paths. If you use a dawn stone on a female, you get the half-ghost Froslass, which is what Crystal is. Letting either gender reach a certain level will get you a Glalie instead, which stays pure ice type. Though it takes a while to evolve them. Rose is still working on evolving hers.