Growth in mineral exploration activity is essential for the future development of the mineral sector and for the economic well-being of Tasmania.
According to the Australian Bureau of Statistics (ABS), expenditure on mineral exploration in Tasmania for the 2007/2008 year was $32.4 million, up 37% on the $23.7 million recorded in 2006/2007. Tasmania's share of expenditure was down marginally from 1.38% to 1.32%.
Tasmania experienced the fourth highest rate of increase, after Western Australia (50%), Queensland (46%) and the Northern Territory (44%), but ahead of New South Wales (32%), South Australia (30%) and Victoria (14%).
Mineral Resources Tasmania data record a higher expenditure of $41.54 million, of which $20.47 million or 49% was spent on exploration licences. This high figure is gratifying in that it shows a strong commitment by the private sector to discover the new deposits needed to sustain the future mining industry.
Buoyant conditions continued in the mining sector in 2007/2008, driven by strong metal prices, including renewed interest in iron ore. The mineral extraction and processing sector is Tasmania's largest export industry, accounting for $2.8 billion worth of production and 53% of mercantile exports, up from 49.4% the previous year.
MRT, by providing information on areas of high mineral resource potential in Tasmania, encourages private sector exploration which will lead to new operations coming on stream as the economic life of existing operations declines. By ensuring an adequate return from our mineral resources, all Tasmanians can share the benefits of our mineral wealth.
Producing mines
Allegiance Mining NL further developed the Avebury nickel mine, with the first production of concentrate in July 2008 and the first shipment expected during the following month. During the year, Allegiance was the subject of a successful takeover by Zinifex Limited (now OZ Minerals Ltd) which was finalised on 18 July 2008. Recent drill intersections in the East Avebury area indicate that further growth in the Avebury resource is likely.
Exploration to further extend resources continued at the Zinifex Limited (OZ Minerals) Rosebery mine, with feasibility studies into potential expansion of surface infrastructure and construction of a new tailings dam commencing. The objective is to extend the life of the mine beyond 2030 at current mining rates.
Bass Metals Ltd delivered the first ore from the Que River mine to Rosebery in August 2007 and at year's end had established a profitable operation, with over 37 500 tonnes of ore delivered during the year.
Bluestone Mines Tasmania Pty Ltd commenced mining tin ore at Mount Bischoff and reopened the Renison Bell mine in July 2008. A feasibility study into recovering tin and copper from the Renison Bell tailings dam continued to yield positive results and work has progressed to detailed design stage.
Stemcor has sold 90% of Australian Bulk Minerals to a consortium of Chinese companies, headed by the Shagang Group. The open-cut mine at Savage River is being expanded with a view to extending mine life by at least 25 years.
Production resumed in the high grade Western Zone of the Beaconsfield gold mine following lifting of the final government restriction limiting underground mining. A new remotely operated mining method has been implemented that enables ore to be extracted without personnel entering active stopes in this part of the mine.
Active exploration programs continued at the Mount Lyell and Henty mines.
Cominex Pty Ltd and Sumitomo Australia Ltd have transferred their silica flour tenements in northwest Tasmania to Tasmanian Advanced Minerals Pty Ltd. Silica flour is used to make LCD screens. The new company has recently received Level II permits to allow for the extraction of 50 000 cubic metres a year at the Corinna mine and the new Blackwater mine. Tasmanian Advanced Minerals Pty Ltd completed the construction of a silica flour treatment plant near Wynyard.
New developments
King Island Scheelite Limited has completed negotiations with the Hunan Nonferrous Metals Corporation to commence the redevelopment of the Grassy scheelite (tungsten) mine and at year's end was waiting on approval from the Chinese government, the final condition to be satisfied before development can commence.
Van Dieman Mines plc has announced that it was investigating a change to the proposed processing plant and mining methods at the Scotia alluvial tin and sapphire mine, near Gladstone. This would result in a delay to commissioning the operation, but would likely result in a decrease in capital costs.
Proto Resources and Investments Limited has successfully completed a scoping study into operating a nickel-cobalt laterite mine and processing plant at the Barnes Hill deposit, near Beaconsfield. The company will continue to conduct metallurgical testing and drilling as precursors to completing a full feasibility study into commencing the operation.
Maydena Sands Pty Ltd has been actively seeking markets for the production of high quality silica flours from Pine Hill, to the west of Maydena. Plans are well advanced for a quarrying operation with a dedicated treatment plant on the proposed mining lease.
Mineral exploration highlights
The high level of expenditure on exploration resulted in significant new drill intersections and announcements of resources that reflect the diversity of metallic minerals in Tasmania.
Venture Minerals Ltd has announced an inferred resource of 20 million tonnes at 33% iron at the No. 2 zone of the Mount Lindsay mine, northwest of Renison Bell. The company also announced a significant drill intersection of iron-tin-tungsten mineralisation at its first hole into the Stanley River prospect further west.
Among other iron ore explorers, Iron Mountain Mining Limited announced shallow drill intersections of magnetite in the Hampshire district.
Bass Metals Limited has several significant drill intersections of zinc-lead-gold-silver-copper ore in the Fossey Zone, the southern extension of the Hellyer mine, including 12.75 metres of 18.5% zinc, 8.8% lead, 0.6% copper, 273 g/t silver and 2.83 g/t gold. Bass has announced a resource of remnant ore at Hellyer of 748 000 tonnes of 7% zinc, 4% lead, 0.3% copper, 87 g/t silver and 1.3 g/t gold. Preliminary studies into mining the Fossey Zone along with the Hellyer remnants have commenced and preliminary metallurgical testing has yielded promising results.
Zinifex Limited reported a 23 metre massive sulphide intersection grading 5.6% zinc, 1.1% lead, 38 g/t silver and 0.8 g/t gold at the Jupiter prospect, five kilometres south of Rosebery.
Zinifex also announced nickel-copper intersections at Melba Flats, east of Zeehan, including 1.9 metres of 1% nickel and 0.8% copper and six metres of 0.8% nickel and 0.7% copper at the North Cuni-Genets prospect; 0.7 metres of 10.8% nickel and 3.81% copper at the Nickel Reward prospect; and 4.7 m of 1.3% nickel and 0.94% copper at the Devereaux prospect.
Intensive exploration continued at the Avebury mine and environs, with new total resources for the Avebury deposit announced at 18.18 million tonnes of 0.95% nickel. There were a number of promising intersections outside the mine area, including eight metres of 1.5% nickel at the Foundation Stone prospect, 1.5 kilometres to the north of the deposit.
Zeehan Zinc Limited announced an Inferred Resource of 1.392 million tonnes of 2.8% zinc, 3.4% lead and 69 g/t silver at the Boss mine near Zeehan.
Stonehenge Metals Limited has announced an Inferred Resource of 562 000 tonnes of 0.5% tin, 1.4% zinc and 36.4 g/t silver at the Sweeney prospect near Trial Harbour and an Inferred Resource of 287 600 tonnes of 2.8% zinc, 1.5% lead and 31 g/t silver at the Sunshine prospect near Zeehan.
Greatland Gold plc has announced results from a twelve-hole shallow drilling program at the Warrentinna goldfield in northeast Tasmania. Best results were three metres of 2.9 g/t gold within intersections of nine metres of 2.06 g/t gold, and 51 m of 0.51 g/t gold at the Derby mine and three metres of 2.1 g/t gold at the Golden Dyke prospect.
Metals X Ltd has announced a resource of copper within the tin ore bodies at Renison Bell of 1.189 million tonnes of 0.81% copper.
