Copper Mines of Tasmania (CMT) owns the historic Mount Lyell underground copper mine and concentrator in Western Tasmania.

CMT was acquired (100 per cent owned) in April 1999 by Sterlite Industries Ltd (SIIL). SIIL is an Indian-based company listed on the Bombay and New York stock exchanges and is in turn majority owned (59.9 per cent) by Vedanta Resources plc, which is a London Stock Exchange listed FTSE 100 international mining and metals company.

The mine is located on the rugged west coast of Tasmania near to the town of Queenstown, approximately 150 km south of Burnie. The mine is at an elevation of 390 m above sea level with local topography exceeding 1000 m. The climate is wet temperate maritime with an annual rainfall of approximately 2.5 m and occasional winter snow. Land tenure is leased Crown land. Figure 1 shows an aerial view of the mine site and Figure 2 shows a view of the concentrator.

Mount Lyell is a long-established operation with numerous orebodies exploited in the area since the 1880s. Historic production from the field exceeds 1.5 Mt copper, 25 million ounces (Moz) silver and 1.6 Moz gold. Current mining is from the Prince Lyell orebody, a large low-grade disseminated chalcopyrite deposit. This was formerly mined as the West Lyell open cut between 1935 and 1972.

FIG 1 - Aerial view of site.

FIG 2 - View of concentrator with Mt Owen in background.

Current mining is at a depth greater than 1000 m below the original surface using the sublevel caving method. There are additional undeveloped Mineral Resources within the mining lease, which include the Western Tharsis deposit and extensions of previously mined orebodies at depth. A production summary is provided in Table 1. A longitudinal projection showing current and historical mine workings is shown in Figure 3.

The concentrator plant employs a conventional comminution, flotation, filtration process to produce a single copper concentrate for export, which includes gold and silver by-products. When operational the company employed approximately 300 full-time equivalent employees comprising 100 CMT employees and 200 employees engaged by the mining contractor. The majority of employees are residential in Queenstown and nearby towns on the west coast.

2010 – 11 (actual) 2011 – 12 (plan)
Ore mined underground (Mt) 1 976 177 2 490 705
Ore milled (Mt) 2 000 057 2 490 704
Head grade Cu (%) 1.23% 1.20%
Head grade Au (g/t) 0.28 0.31
Copper produced (t) 22 929 27 538
Gold produced (oz) 12 347 16 880

TABLE 1 – Production Summary

FIG 3 - Longitudinal projection showing current and historical mine workings and deposits.