Prominent Hill Mine
Prominent Hill open pit in september 2008
|Production||Copper: 60,145 tonnes
Gold: 90,821 ounces
Silver: 361,767 ounces
|Financial year||2009-10 |
|Website||OZ Minerals website|
The Prominent Hill Mine is a major copper, silver and gold mine in north west South Australia, 130 km south-east of Coober Pedy, which has been developed by Oxiana Limited, later to become OZ Minerals. The deposit is an iron oxide copper gold style mineralisation.
The mine has cost A$1.15 billion to develop, and it is projected to produce 100,000 tonnes of copper and 115,000 oz of gold in concentrates a year.
The mine went into production in February 2009. The development includes an open-pit mine, a conventional grinding and flotation processing plant, construction of a permanent village to accommodate the workforce and construction of a haulage road, power line and bore field. Studies for underground development are underway.
Resources of the deposit are 152.8 Mt at 1.18% Cu, 0.48 g/t Au and 2.92 g/t Ag plus 38.3 Mt at 1.17 g/t Au of non-sulfide ore.
In contrast to the Olympic Dam deposit, an iron oxide copper gold deposit of similar age about 200 km to the southeast of Prominent Hill, uranium values do not exceed 150 ppm and therefore uranium recovery is not economical.
The mine was part of the sale of its assets by OZ Minerals to Minmetals Australia Pty Ltd but was blocked by the Australian Government, citing national security concerns. Wayne Swan, Treasurer of Australia, stated that Prominent Hill could not be included in the sale as it was within a sensitive military area and the sale of the other OZ Minerals mines only went ahead after Prominent Hill was excluded.
Geology and mineralogy
The deposit is located in the Gawler Craton and it is hosted mainly in a fault zone where Hiltaba-Suite granites overthrust a Mesoproterozoic volcano-sedimentary sequence. The age of the mineralisation is about 1.58 billion years. It consists of a breccia containing host rock clasts (dolomite, sandstone, andesite) which is intensively hematite, chlorite and sericite altered. Major sulfide minerals are pyrite, chalcopyrite, bornite and chalcocite.
- The Australian Mines Handbook: 2003-2004 Edition, Louthean Media Pty Ltd, Editor: Ross Louthean
- Quarterly Report Presentation - June 2010 OZ Minerals ASX announcement, published: 16 July 2010, accessed: 31 July 2010
- "Construction costs rise for Australian miner". International Herald Tribune. 2007-10-31. Retrieved 2008-08-29.
- Prominent Hill OZ Minerals website, accessed: 12 January 2010
- First production from Prominent Hill copper-gold operation OZ Minerals ASX announcement, published: 26 February 2009, accessed: 12 January 2010
- "PIRSA - Prominent Hill". Retrieved 2009-04-23.
- Australia Blocks China’s Purchase of Mining Company The New York Times, published: 27 March 2009, accessed: 11 January 2010
- Belperio, A., Flint, R., Freeman, H. (2007). "Prominent Hill: A Hematite-Dominated, Iron Oxide Copper-Gold System". Economic Geology 102: 1499–1510. doi:10.2113/gsecongeo.102.8.1499.