1968 Underground sampling at the Mt Diamond Copper Mine

Abstract

Underground chip-channel sampling at the Mt. Diamond Copper Mine has indicated a possible 18,500 tons of ore in a zone 4 foot wide having a grade of 3.8 percent copper and 3.0 oz silver per ton. The ore lies within a planar, steeply dipping quartz limonite shear zone in hornfels near a grranite contact. There is a well developed supergene enrichment zone, partly oxidised as a result of later uplift of an ancient peneplain, which contains chalcocite, chalcopyrite, cuprite, arsenopyrite (probably silver bearing) and a little pyrite. The primary zone consists of chalcopyrite, arsenopyrite and pyrite veins, pods and stringers associated with brecciated and massive quartz and limonite. The ore contains 0.09 percent bismuth. This may be detrimental to its value as a penalty is charged at smelters for bismuth content in copper ores. Some drilling from the surface has been carried out, and more is required to fully test the viability of the deposit. Proved, probable and possible reserves with varying grades have been outlined, together with a small tonnage of surface dump material of potential ore grade.