Source : Webster's Revised Unabridged Dictionary (1913)

Mineralogist \Min`er*al"o*gist\, n. [Cf. F. min['e]ralogiste.]
   1. One versed in mineralogy; one devoted to the study of
      minerals.

   2. (Zo["o]l.) A carrier shell ({Phorus}).

Source : WordNet®

mineralogist
     n : a scientist trained in mineralogy