Ilgarari, Bulloo Downs Station, Meekatharra Shire, Western Australia, Australiai

Regional Level Types
Ilgarari	- not defined -
Bulloo Downs Station	- not defined -
Meekatharra Shire	Shire
Western Australia	State
Australia	Country

A historic copper mine, 270 kilometres north-north-east of Meekatharra, and 16 kilometres west of the Great Northern Highway on Bulloo Downs Station. Lead-zinc, manganese, onyx and banded agate have also been reported from the area.

The copper mine is divided into two parts, Ilgarari Main and Ilgarari North-East, 1.3 kilometres apart, on a flat featureless plain. Mineralisation covers an 8 kilometre north-south line following a fault. The area is in the Proterozoic Bangemall Basin, and the Collier Sub-Group of this, underlain by the shallow dipping Ilgarari Sub-Group comprising siltstone and black/grey shale.

A lease at Ilgarari is mentioned briefly in 1906, and then several reports of copper ore being mined from 1914-1918. In 1929 it was reported a local syndicate had taken up two leases at Ilgarari and had mined 520 tonnes of ore for 200 tonnes of copper. The ore was bagged unprocessed and taken by truck and rail to Geraldton for shipment to the Port Kembla smelter (NSW). The Inspector of Mines in this year reported the following at Ilgarari: 'I panned off samples from a dump and found it contained gold also, although I was told that the mine owners were only paid for the copper contents'. In 1940, R. Reid was prospecting at the leases.

To 1913 from the Main deposit, 724.34 tonnes of cupreous ore had been mined at 12.08% Cu, then to 1970 526.19 tonnes of copper ore. Mining took place at the Ilgarari copper mine between 1968 to 1973 by Group Exploration Limited, after raising substantial public funds. They sank the Alac Shaft. They mined oxidised mineralisation to 61 metres below the surface as an underground mine, 528.47 tonnes from Ilgarari North-East of cupreous ore at 27% Cu, and 1381.51 tonnes of copper ore. The mine closed in 1973 due to insufficient capital, an inadequate plant, and little-planned exploration.

The deposits are hosted by north dipping to horizontal grey (white when weathered) laminated siltstone, sandstone, and shale, with disseminations and veinlets of pyrite. This is intruded by dolerite dykes and sills, also containing pyrite. Copper mineralisation at Ilgarari North-East is set in steep south dipping vuggy faults and shears at the dolerite/shale contact. At Ilgarari Main fine-grained chalcocite, cuprite and malachite are found in a vein 25 metres long in shale.

The mineralised area contains 0-12 metres of malachite, azurite, chalcopyrite, cuprite and chalcocite; 12-38 metres of the above minerals as well as more abundant cuprite and chalcocite, with minor native copper; 38-130 metres of chalcocite and chalcopyrite.

Other Regions, Features and Areas containing this locality

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