Applied crystal chemistry, earth materials

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My research focuses on the chemical and structural-state characterization of minerals (and their synthetic analogues) associated with magmatic ores.  The long-term goal is to apply obtained data as a means of quantifying the geological conditions under which these minerals developed.  Currently, I am most interested in applying data obtained from analyses of minerals in the Fe-Ni-Cu-PGE system to quantitatively assess primary conditions of crystallization and growth and secondary processes that may have modified them.This work currently involves two directives, the first involving Fe-Ni sulfides (Pyrrhotite Mineral Family, PMF).  Pyrrhotite is a family of Fe-deficient sulfides that constitute the most abundant sulfide in magmatic ore deposits.   The PMF exhibits fairly simple phase relations at T >350 °C, but complex relations below this, owing to the way that Fe ions and vacancies are arranged.  In general, two basic PMF minerals are known, hexagonal (hpo) and monoclinic (mpo) pyrrhotite, and understanding how the two vary in terms of modal abundance, their intergrowths, minor-element chemistry, etc. is critical to assessing how an ore body has evolved.  My goal is therefore to determine the hpo:mpo ratios in natural ore bodies to apply the data obtained as means of understanding how the chemistry and conditions of formation have been modified with time.  The second directive involves Platinum-Group Minerals (PGM) that host the economically and technologically important Platinum-Group Elements (PGE).  Traditionally, PGM have been poorly understood owing to their small grain sizes, complex and highly varied chemistries and because of their overall rarity.  However, PGE constitute important industrial commodities, owing to their use in high-tech industries (fuel cells, electronics) so an understanding of PGM and how they can be found is important.  My research goal is to resolve some of the outstanding complexities associated with these minerals, through analyses of the atomic arrangements, and to combine results from studies into their synthesis with field-based data as a means of understanding their formation.