Mount Isa Mines tetrahedrite as ore minerals along with common accessories pyrite, pyrrhotite, quartz, carbonates and graphite. Minor arsenopyrite, marcasite, chalcopyrite, valleriite, proustite, polybasite and argentite also occur. Original surface oxidized ore contained cerussite, anglesite and pyromorphite. Silver and zinc were removed from the surface oxidized zone and were deposited as supergene ore at a depth above the primary ore. Copper occurs in brecciated "silica-dolomite" rock. Primary minerals are chalcopyrite, pyrrhotite and arsenopyrite. minor amounts of cobaltite, marcasite, valleriite, chalcostibite, galena and others are reported. Smelter operations release sulfur dioxide emissions very close to the city of Mount Isa. The Mount Isa Mines
Broken Hill ore deposit hornblende schists. The ore consists of massive, recrystallised sphalerite-rich, galena-sphalerite and galena-rich sulfide lenses in folded horizons, known as No. 2 Lens Formation and No.3 Lens Formation. Both have distinctive metal ratios and gangue minerals. The ore boundaries are parallel to the bedding planes. According to Gustafson, "There is evidence that the ore has been introduced into an old, already folded, rock and has replaced certain favourable layers of that rock, particle by particle, with large tonnages of garnet, rhodonite, fluorite, marmatite (and wurtzite), galena, and other minerals that constitute the orebodies." The Potosi-Footwall Gneiss is found on both sides