| The minerals industry is the cornerstone of Tasmania’s economy. It is important to the lives of every Tasmanian and brings with it a rich economic and cultural heritage and a capacity to ensure a prosperous future for Tasmania. |
| The rocks making up Tasmania occupy much of Earth’s geological history. The geology is complex and unique and lends itself to a very active minerals exploration and mining industry. The west coast of Tasmania is world famous for its geology and mineralisation.World class mineral deposits lie in an arc of volcanic lavas from Low Rocky Point in Tasmania’s South West, northwards through the great mining areas of Mt Lyell, the Dundas mineral field, Henty, Zeehan mineral field, Renison Bell, Rosebery, Tullah, Que River and Hellyer then eastwards to the Moina mineral field near SheffieldSuper-hot metal bearing fluids associated with undersea volcanism in the Cambrian Period approximately 600 million years ago, poured out onto a deep sea floor to form the copper, lead, zinc, silver and gold ore deposits presently being mined at the Mt Lyell, Rosebery, and Henty (gold only) mines. |
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| Numerous other mines which extracted similar ores in this same belt have since closed, for example at Tullah, Hercules, Hellyer and Que River. However, valuable minerals in the Hellyer Tailings Dam are being recovered in a dredging operation and the Que River mine has been re-opened as an open cut operation. |
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In the Devonian Period around 370million years ago granite was the source of rich metal-bearing fluids that formed tin deposits at the Renison Bell mine and silver, lead and zinc deposits around Zeehan and at the Dundas and nickel at the Allegiance mine near Zeehan.In North East Tasmania granite is also the source of tin, tungsten and copper in mines long closed near Scamander through to Gladstone in the far north east. Gemstones such as topaz, zircon and sapphires are found associated with the north east granites. Similarly, granite has been responsible for the rich tin and tungsten deposits at Rossarden, Storeys Creek, Ben Lomond and further south at Royal George. There are old tin mines near Luina and Magnet near Waratah, Coles Bay and at Melaleuca in the far south near Port Davey. In fact, wherever granite is found in Tasmania, ore deposits, and particularly tin, are never far away. Granites on the west coast have not only generated the tin deposits of Renison Bell, but are also responsible for nickel deposits recently found and presently being assessed at Avebury and Melba flats north of Zeehan.The same granites are presently being assessed for their thermal capacity to be able to generate heat to produce “hot rock” thermal power.Further west from Waratah lies a belt of Pre-Cambrian volcanic lavas, which extend north eastwards to Burnie and out into Bass Strait. The high grade iron ores mined at Savage River form part of this mineralised belt. The iron concentrate produced from the mill at Savage River is pumped as a slurry through an 80km pipeline to Port Latta, where it is converted into pellets ready for shipment overseas. While iron in the form of magnetite is the primary ore mined at Savage River, the locality also witnessed many of Tasmania’s early gold rushes and later, alluvial gold and tin mining. |
| Gold is mined exclusively at the new Henty Gold Mine south of Rosebery and at the rejuvenated Beaconsfield Gold Mine. Though not mined in its own right, it is also extracted from the Mt. Lyell and Rosebery ores. Gold exploration is re-focussed towards the abandoned gold mines in North and north east of Tasmania – the Lefroy – Back Creek area, Golconda, Alberton, Mathinna and Mangana. Gold and other metals are high on the exploration agenda in Tasmania.Extensive aerial surveys using remote sensing techniques to discover and pinpoint areas of interest, called anomalies, have been conducted across the state by a number of exploration companies. Sensitive instruments suspended beneath helicopters and planes measure the gravitational attraction, magnetism and radiation of rocks at and beneath the surface. Aerial borne radar surveys have yielded very accurate images of the rock surface beneath the soil and vegetation cover. |
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| On-the-ground exploration involves survey teams adopting well proven historical methods like hand sampling and panning to highly sophisticated techniques using satellite and radar imagery, geochemical analysis of rocks, soils and water, and geophysical techniques which include seismic, gravity, electrical and magnetic surveys. All involve the use of modern computer based technology to prove or disprove the existence of a prospective ore body. Final proving up the existence of a mineable orebody involves diamond drilling. Many exploration drill rigs operate in Tasmania. |
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Mineral processing takes place at several sites in Tasmania. At the TEMCO smelter at Georgetown, manganese ore, iron ore and coal from mainland Australia are mixed with local quartzite and limestone to produce ferro- and silico-manganese alloys that are so important in overseas steel industries.At the Rio Tinto Aluminium (Bell Bay) smelter, also near Georgetown, alumina produced from bauxite in Queensland is converted to aluminium metal. Downstream industries next to the Rio Tinto Aluminium (Bell Bay) site use the raw aluminium to produce such products as the aluminium powder used in explosives and in metallic paints.At Risdon near Hobart the Nyrstar Hobart Smelter uses zinc mineral concentrates to produce zinc metal, with lead and cadmium as minor products. By products of the process are sulphuric acid which is used to make farm fertilizers and jarosite, which is transported to Port Pirie in South Australia for further processing. |
| At Railton, in Tasmania’s central north, one of the world’s largest deposits of limestone is mined to provide Cement Australia with the raw material to make Portland cement. While the raw cement is distributed statewide and used to cement fill in west coast underground mines, the bulk is shipped out of Devonport to mainland Australia.Coal is used at Railton to produce the large quantities of heat required to produce the cement. Bituminous coal is mined by the Cornwall Coal Company at the Blackwood and Duncan underground collieries near Fingal and the Cullenswood and Kimbolten open cut mines. Coal is cleaned at a washery in Fingal, then distributed by rail. Other than for cement, coal is used to produce steam in such industries as the Cadbury Chocolate Factory, the Cascade Brewery in Hobart and the paper mills at Boyer and in Burnie. Total production is limited to providing the local market which is small by mainland standards |
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Numerous supply companies provide much needed services and supplies to the industry. Most notable of these is Caterpillar Underground Mining Ltd, a world renowned company based in Burnie that designs, constructs and distributes underground mine machinery.Most of the underground mines in Tasmania use Caterpillar equipment somewhere on site, and most large mines on mainland Australia boast “a Caterpillar or two”. Similarly, Atlas Copco provide specialist mine equipment to Tasmanian mines.Haulmax in Wynyard designs and manufactures heavy duty haul trucks capable of hauling ore long distances. |
| Of the many and varied services supplied to the mines, environmental consultancy and management is integral to any operation. The rugged landscape, unpolluted waterways and rich diversity of fauna and flora in Tasmania, combined with a commitment by the industry to best practice environmental management, ensure minimal visual, physical and social impact of company operations. Tasmanian minerals operations, particularly mining operations, lead the world in environmental best practice, with unique environmental management technology being exported worldwide. |
