Apatite in the Olympic Dam Fe-Oxide Cu-U-Au-Ag Deposit

Apatite from igneous rocks hosting the World class Olympic Dam iron-oxide-copper-gold deposit, South Australia is characterized with respect to morphology, chemistry, mineral assemblage and grain-scale compositional zoning. In granites, apatite displays a characteristic core-to rim zonation due to REE content. Fields of dusty monazite as 'emulsion'-like cores or symplectite intergrowths with host apatite are recognized. Compositional data, and their correlation with textures, show a complexity but nevertheless, potential for characterizing the igneous-to-hydrothermal evolution at Olympic Dam. Knowledge of the evolution and geochemistry of apatite at Olympic Dam may offer insights into deposit formation and, potentially, be a tool to discriminate Cu-Au mineralized and barren Fe-oxide dominated hydrothermal systems.