Chromite (Cr) occurs exclusively in mafic and ultramafic igneous rocks (Papp and Lipin, 2006).Although some Cr-based minerals such as crocoite (PbCrO 4), vauquelinite (Pb 2 Cu[CrO 4][PO 4]), uvarovite (Ca 3 Cr 2 [SiO 4] 3), and merumite (4(Cr,Al) 2 O 3 ·3H 2 O) are well known, chromite (FeCr 2 O 4) is the only one that is a commercially recoverable …