Broken Hill ore deposit Wikipedia
The PotosiFootwall Gneiss is found on both sides of the main lode. The ore often consists up to leadzinc sulfides, with little or no pyrite, chalcopyrite or gangue sulfides. The footwall to the mineralization is a psammopelite gneiss, consisting of feldspar, quartz, garnet, biotite and amphibole, with a pelite gneiss on the hanging wall