The Collaborative International Dictionary of English v.0.48:
Crystallographer \Crys`tal*log"ra*pher\ (kr[i^]s"tal*l[o^]g"r[.a]*f[~e]r), n. One who describes crystals, or the manner of their formation; one versed in crystallography. [1913 Webster] CrystallographicWordNet (r) 3.0 (2006):
crystallographer n 1: a specialist in crystallography