Nifty Cu Mine, Rudall River District, East Pilbara Shire, Western Australia, Australiai

Regional Level Types
Nifty Cu Mine	Mine
Rudall River District	Mining District
East Pilbara Shire	Shire
Western Australia	State
Australia	Country

Located about 68.5 kms West of Telfer, SSE of Port Hedland.

Potentially this mine could provide a major source of fine secondary copper specimens to the collector market, if only the mine operators could see the value of such an exercise. Like many copper deposits in arid areas, the oxidised zone has retained an abundance of species.

The mine is located on the western edge of the Great Sandy Desert, 70 kilometres west of the Telfer gold mine. Access is via a private road from the Woodie Woodie manganese mine, to the west. It is approximately 450 kilometres south east of Port Hedland.

Surface evidence was difficult to locate due to the over-lying sand dunes, but a malachite stained outcrop was discovered by Western Mining Corporation in 1981. Drilling by 1983 had identified a deep sulphide resource, and Western Mining started open pit mining of the oxide zone. Straits Resources purchased the mine in 1998, and then Aditya Birla Minerals in 2003. Open pit mining of the chalcocite ore ceased in 2006, and underground mining of the chalcopyrite ore started in 2009. The expected mine life is at least nine years. The ore is trucked to Port Hedland, then shipped to India to be processed. The company is also exploring the Maroochydore copper deposit to the south east.

The Nifty deposit is hosted by the late proterozoic (1700 Ma) Broadhurst Formation, which is part of the Yeneena Group. Zones are from bottom up: footwall- thinly laminated carbonaceous pyritic shale, micaceous and chloritic siltstone and minor light grey dolomitic mudstone; Nifty Member- 40-70 metres of dolomitic mudstone interbedded with carbonaceous shale and quartz dolomite alterations; 4 metres of grey black chloritic shale with pseudomorphs after evaporite rosettes; Pyritic Marker Bed- 25-60 metres of blue black carbonaceous shales with abundant pyrite; Hanging Wall- beds of laminated dark grey to black pyritic carbonaceous silts and shales. Most of the primary and secondary mineralisation is in the Nifty Member, extending up to 40 metres into the hanging wall.

Copper mineralisation is thought to have occurred from regional compression, resulting in hot, saline, slightly acidic ground-water, increasing the pH, precipitating copper. This is found in sheets to 20 cm across and 2mm thick matching the shale bedding planes. It is also found as pods, stringers and vein networks. Calcite and cuprite is found in association with the copper in these networks. Cuprite is said to be abundant.

The oxidised zone extends from the surface to 100 metres, and is dominated by malachite and azurite, with minor atacamite, and chrysocolla. There is then a transitional zone of native copper with malachite and azurite, and minor chalcocite below this at the current water table. Below this is high grade chalcocite as the primary sulphide. In this last zone is the Nifty Member containing chalcocite, pyrite, sphalerite, galena, and trace pyrrhotite. The malachite comes in a variety of habits, including mats of fine acicular crystals, and flattened sheaves up to 3mm long. Groups of malachite crystals are found associated with doubly terminated clear drusy quartz crystals.

The species found is similar to Telfer, both sharing similar geology and formation processes. Unlike Telfer, no gold is found at Nifty. No phosphate species are found at Telfer.

In 2000, staff from the Western Australian Museum were able to access the oxidised ore stockpiles, and collected a treasure trove of specimens. Mark Creasy and David Vaughan hold specimens that somehow found their way into the Blair Gartrell Collection in the early days of exploration. Specimens beyond this in private collections are unknown, but probably rare. If they do exist, the owners are likely to keep quiet about it till well after the mine has closed.

The Nifty copper deposit was discovered by Western Mining Corporation in 1980 using rock chip and regolith sampling. Mining commenced in 1993 and continued until 2019, producing 720 kt of Cu until being placed into care and maintenance. In March 2024 the deposit still had a measured and indicated resource of 119 Mt at 0.84 % Cu totaling 1 Mt of contained copper. Three phases of mineralisation: (1) an early Stage 1 clastic-dominated zinc–lead style formed between 840 and 810 Ma, (2) a stratiform, disseminated Stage 2 chalcopyrite ± dolomite assemblage emplaced from around 720 Ma, and (3) a Stage 3 episode characterized by massive vein and breccia chalcopyrite mineralisation occurring between 680 and 620 Ma.

Other Regions, Features and Areas containing this locality

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