Mining and Minerals Production

Introduction

This content is currently under review. Statistics date from 1990.

Mining has long been important in the Murray-Darling Basin and the Basin occupies a significant place in the history and development of mining in Australia. The search for minerals, especially gold and the early goldrushes, played an important part in European exploration, settlement and, in turn, agricultural development of many parts of the Basin in the nineteenth and early twentieth centuries. Australia's first payable gold discovery was made at Ophir, near Orange, in 1851, and this started the massive goldrushes that took place in many parts of the country. Over the next twenty years, other important gold discoveries were made at such New South Wales locations as Young, Bathurst, Gulgong, Grenfell, West Wyalong, Forbes, Parkes, Armidale, and Temora (where the 'Mother Shipton' gold nugget with 259 ounces of fine gold was found in 1882, which had a population of over 20,000 in 1880). Similar developments occurred in Victoria, as in the alluvial workings in the Ovens Valley-Beechworth area, while underground and alluvial mining provided the commercial stimulus for the development of such towns as Bendigo, Castlemaine, Maryborough, Stawell and Ararat. Some mines became very well known, such as the Eldorado alluvial mine near Wangarratta, which operated until the early 1950s*.

Gold discoveries had a tremendous impact in all parts of Australia. From 1851 to 1861, Australia's population trebled. In Victoria alone, the population doubled in one year and increased five-fold in the ten year period. The goldrushes not only brought increases in population and changes to society, but also tremendous increases in wealth. For example, in the ten years to 1861, Victoria produced 750 tonnes of gold, some 40 per cent of the world's output in that period.

The Murray-Darling Basin was also the location for the early discovery of other minerals. Copper was discovered at Burra in 1845 and by 1850, it was the largest metalliferous mine in Australia, producing 5 per cent of the world's copper: the old mine is still famous as a source of museum specimens of green malachite and blue azurite (Grguric et al. 1995). In 1883, silver, lead and zinc were found at Broken Hill. Opals were first discovered at White Cliffs in 1889. In 1900, the first Australian discovery of petroleum products was made at Roma.

Mining is now a significant part of the Basin's heritage resources and tourism and recreation industry, in terms of former mines (of which there are many throughout the Basin, together with mining museums), active mines, and fossicking for gem stones in such parts of the Basin as the Northern Tablelands of New England (McGowan 1994; Shackleton & Binnie 1993). It can also be noted that the mining industry has left its mark on the landscape in many areas, such as the Ovens Valley-Beechworth area where spoil from the alluvial workings and dredgings in the mid to late 1800s continues to present land use problems.

* : This page is based on a number of sources (Anon. 1994; Gold 1994; Moffatt 1992; Oliver & Townsend 1993; Parbo 1992; Shackleton & Binnie 1993; Wilkinson 1994; Ewars 1998), updated by media reports.)

Mining today

Mining makes an important contribution to the overall economy of the Murray-Darling Basin, with 'Sales of Goods and Services by Mining Operations' valued at $1,660 million in 1992-93, some 5.3 per cent of the Australian total of $31,369 million (Table 1). The industry employs 5,490 people, 8.3 per cent of the Australian total. Mining is not evenly spread over the Basin, but is concentrated in particular locations. For these towns and regions, it makes a major contribution to every aspect of their economic and social lives. Figure 1 shows the location of major mining activities (with the exception of such commodities as sand, gravel and construction materials) and the oil and natural gas pipelines that cross the Basin. Table 1 gives data on numbers of mines, employment, wages and salaries, and the value of sales of goods and services for major mineral commodities. (Data are restricted by the confidentiality clauses applicable to the release of information by the Australian Bureau of Statistics. This explains why the column totals are greater than the sums of the rows.)

Mining in the Basin displays considerable variety, in terms of the minerals mined, the nature of the mining operations, the value of their operations, and locations (Figure 1). Many of Australia's best known mining company names are involved in mining and mineral exploration in the MDB, for example, BHP (which had its origins in Broken Hill), North Ltd, Newcrest, MIM, Pasminco, Rio Tinto, Santos and Boral. There are also numerous small and medium sized companies.

Figure 1 Mining in the MDB

Metallic minerals

Copper

Copper is one of the Basin's most important minerals. It frequently occurs in conjunction with other minerals, in particular, lead, zinc, silver and gold. The deposits are primarily in the Lachlan Fold Belt, which extends from the south coast of New South Wales north-west to Bourke. Most of the current, former and potential mines are located in the northern and central parts of the Belt. One of the main centres has been Cobar, where copper was first discovered in 1870. Copper is mined in conjunction with gold, lead, zinc and silver at the Peak Mine, but the closure of the CSA Mine in January 1998 has had a major impact on the town. There is a small copper and gold mine at Mineral Hill, north-west of Condobolin. At Girilambone, north-west of Nyngan, a new copper mine started production in 1993, the processing method making it among the lowest cost copper producers in the world; exploration work is continuing on promising ore bodies in the area, especially at nearby Larsen's East.

The Orange-Parkes area is emerging as a significant copper and gold province. North of Parkes, the large Northparkes copper and gold mine began operation with gold production in 1994 and copper following in 1995. The size of the resource was nearly doubled in mid-1995.

Considerable exploration work is being undertaken throughout the Lachlan Fold Belt, including such locations as Condobolin and Lake Cowal (on gold-copper deposits).

Lead-zinc-silver

These three minerals frequently occur together and along with other minerals, as indicated above. The main mining centre has long been Broken Hill, the largest producer of these minerals in Australia. Cadmium and antimony are produced as by-products. The mines are operated by Pasminco, formed in 1988 from the of the silver-lead-zinc operations of North Broken Hill Peko and CRA. Most of the lead concentrate is smelted at Port Pirie, the location of the sole producer of refined lead in Australia. Of the older mines, only the Southern Mine is now being worked at Broken Hill, the Northern Mine having been closed in 1994 after 90 years of operations. The new Potossi open-cut mine will yield an expected 1 million tonnes of lead-zinc ore over its six year life, with a period of underground mining to follow. With current reserves at Broken Hill only sufficient for about another 10 to 15 years of operations, new deposits are critical to the future economies of Broken Hill and Port Pirie. Much exploration continues in the Broken Hill area, though some work has been halted due to claims of Aboriginal sacred sites. The important Broken Hill Exploration Initiative, a joint federal-New South Wales-South Australia program is continuing (Haren et al. 1995). Some finds have been made and there are prospects of further mining developments.

Pasminco's Elura Mine, to the north-west of Cobar, was opened in 1983 and produces zinc, lead and silver. Over 800,000 tonnes of ore are mined per annum and this is being increased to 1.2 million tonnes. Estimated reserves have recently been increased to 20 million tonnes. Mineral exploration work continues in the Cobar area.

To the north east of Canberra, on the very eastern edge of the Basin (strictly speaking, part of the area of internal drainage that drains to Lake George), is the Woodlawn Mine. Until it closed in March, 1998, it produced zinc, lead and copper, together with small amounts of silver and cadmium.

Other metallic minerals

A number of other metallic minerals are mined in the Basin, including tin and tungsten at Tingha, tin at Ardlethan, Gibsonvale and in the Stanthorpe area, iron oxide for cement manufacture and coal washing at Tallawang, near Gulgong, and magnesite near Young (one of only two such mines in Australia). Mineral sands (titanium) are mined at Horsham; a rutile-zircon mine near Ballina closed in 1992. It is estimated that mineral sands reserves to the value of over $2 billion exist in the Murray Basin. A waste management company has proposed using a disused tin mine at Ardlethan to dump solid household waste transported by rail from Sydney, as well as treating tailings from former mining to yield up to 1,700 tonnes of tin a year over ten years (The Australian, September 28, 1995).

Precious metals and other minerals

As indicated above, gold and silver are produced in conjunction with other minerals at a number of large mining operations.

Gold

In addition to its production in conjunction with other minerals, there are many other mines where only gold is produced. These range from very small underground and alluvial workings, very similar to those of the last century (as in the Ophir area), to very modern operations. Some of these involve the re-working of formerly worked deposits, including their tailings. Others are new mines. Much of the activity continues in areas that were the scenes of the goldrushes, such as the Ovens Valley-Beechworth area and the Bendigo district in Victoria, where one company has recently discovered a large mineralised structure with significant gold content (Hextall 1995). Unusual finds continue to be made, such as an 8.8kg gold nugget found near Bendigo in mid-1995.

In Victoria, most of the many operations are on a relatively small scale. The largest mines are at Stawell (WMC Limited is a partner in Stawell Joint Venture), Nagambie, Maldon, and in the Bendigo district. There continues to be much re-investigation of the old mining areas, both alluvial and deep mining, such as in the Avoca and Beechworth areas. New mines are being developed in the districts of Bendigo and Woods Point-Walhalla.

In New South Wales, the largest gold operation is the Peak Mine near Cobar, with an annual production of over 120,000 oz of gold (as well as copper, silver, lead, and zinc).. A number of other deposits are being developed and explored within the Lachlan Fold Belt, especially in the Parkes, Orange and Cobar districts, many of them in conjunction with other minerals. One of these is Newcrest Mining's Cadia Hill and Cadia East gold and copper deposits west of Orange. Cadia Hill will start production in late 1998 and, over a projected life of 12 years, will produce 300,000 ounces of gold and 23,000 tonnes of copper a year, which will make it the largest gold mine in NSW and one of the largest in Australia. The nearby Ridgeway deposit has a potential of 200,000 ounces of gold a year. North Ltd's proposed mine at Lake Cowal, near West Wyalong, has been halted on environmental grounds, but is now expected to go ahead. The largest single-purpose gold mine in NSW, the Gold Mines of Australia mine at Temora, with annual production of up 41,000 oz, ceased production in late 1996.

In the Queensland portion of the Basin, there is a gold mine at Warroo, east of Inglewood.

Silver

As indicated, silver is produced in conjunction with other minerals at a number of mines.

Opals

Australia accounts for 95 per cent of world's natural opal production, which is valued at over $110 million annually. The Murray-Darling Basin accounts for more than half of the total. The major centres are in New South Wales, at Lightning Ridge-Coocoran, home of the black opal and where major new discoveries were made in the 1980s, and White Cliffs. Major exploration work continues in the area north from Lightning Ridge to Hebel, on the Queensland border, together with something of an 'opals rush'. South-west Queensland accounts for almost a quarter of the State's $1 million opal production, with a number of the locations being in the Basin, including Yowah, Eulo and Duck Creek.

Sapphires

There are numerous occurrences of sapphires along the eastern margin of the MDB, mainly the New England area, but the only mines are in the Inverell-Glen Innes district, one of the world's largest producing areas. Over the period 1960-1990, production of rough sapphire from the alluvial workings was valued at over $250 million.

Other gemstones

There are numerous occurrences of other gemstones, including diamonds, but the only mining operations are for emerald at Emmaville and rhodonite near Tamworth.

Energy minerals

Coal mining

The MDB's main coal mining area is to the north-west of Lithgow north to Rylestone, where the Basin's boundary straddles an area of major coal deposits. There are a number of underground mines and others are proposed. Huge coal deposits underlie the Namoi Valley, but one of the two mines in the Gunnedah district closed in February, 1998; the other remains in operation. However, other coal mines have been proposed for the area. There is a small mine at Ashford, north-west of Glen Innes, which supplies coal for a small nearby electricity generating station. A large deposit of low grade coal exists at Oaklands in the Riverina. It has been the subject of considerable investigations for use as fuel for a major thermal power station to serve New South Wales and Victoria.

In South-east Queensland, the large coal reserves of the Moreton and Surat Basins lie under a significant area of the Darling Downs. The first mine in this area has recently been opened at Kogan Creek, between Dalby and Chinchilla. Given the size of the deposits in the area, other mines are certain to be established. Large deposits of sub-bituminous black coal exist in the Anna-Sedan area of South Australia's Murray Valley.

Oil and gas in Southern Queensland

Australia's earliest gas and condensate discoveries were made in the Surat Basin near Roma in 1900. Some sixty years later, it was another discovery in the same area, namely the discovery of oil at Moonie, that stimulated Australia's oil and gas exploration boom of that decade. The deposits became Australia's first commercial oilfield in 1964 with the construction of the 307 kilometre pipeline from Moonie to Brisbane. This pipeline has been linked to the one that carries oil from the Jackson fields of the Cooper-Eromanga Basins in south-west Queensland, to the west of the MDB. The Moonie Field reserves are now in decline.

The major exploitation of the area's gas deposits also dates from the same period. Gas is piped from the various wells in the Roma, West Surat and South Surat Oil and Gas Fields (as well as numerous other small gas and oil fields) to the liquids separation plant at Wallumbilla, near Roma, from where a 450 kilometre pipeline takes the gas to Brisbane. Another gas pipeline, constructed in 1990, runs from Wallumbilla north and north-west to Gladstone and Rockhampton, with connections to the South Denison Gas Field (just within the MDB) and the North Denison Field (outside the MDB). A new 760 kilometre gas pipeline is being built from the Jackson-Naccowlah-Durham Downs Fields in south-west Queensland to Wallumbilla.

Other non-metallic minerals

Numerous other minerals are mined within the Murray-Darling Basin, quite apart from the many deposits of sand, gravel and other construction materials. They include gypsum near Albury and near Mildura; limestone at Kandos-Rylstone in New South Wales and Elbow Valley and Riverton in Queensland; kaolin at Pittong and Knowsley in Victoria and Puggoon in New South Wales; bentonite near Miles in Queensland; diatomite near Barraba; salt at Blanchetown and Langhorne Creek in South Australia, and Lake Tyrrell, Hattah and Kerang in Victoria (the latter using ground water); silica at Tailem Bend; a vermiculite deposit west of Narromine; and high quality building stone at a number of locations including near Swan Reach (sienna brown granite) and Toowoomba (sandstone).

The future of mining in the Basin

The current contribution of the Murray-Darling Basin to Australia's mining industry is relatively small. However, as has been indicated, this is not a fair reflection of its historical significance or of its importance at a number of locations in the Basin. More importantly, whilst some mining operations will inevitably close, the potential for expansion is considerable, both from known mineral deposits and as a result of continuing exploration in all parts of the Basin. For example, the potential for new gold deposits in the Central West of New South Wales is considerable, as are the coal deposits in the Gunnedah Basin and the Darling Downs (in the Moreton and Surat Basins). However, the exploitation of some mineral deposits could be restricted by competing uses for land and other resources.

References

ABS (1994): Mining Industry Australia 1992-93. Catalogue No. 8402.2. Australian Bureau of Statistics, Canberra.

Anon. (1994): The Australian Mining Companies Directory 1994. Minmet Australia Pty. Ltd., Perth.

Ewars, G.R. (1998): Australian Mining operations and Significant Mineral Deposits: commodities and operating status. 1:5,000,000 map. Australian Geological Survey Organisation, Canberra.

Gold, G.M. (Editor)(1994): 1994 Asia/Pacific Mining Yearbook and Suppliers Source. Australian Journal of Mining, Melbourne.

Grguric, B. et al. (1995): Minerals of the Burra Mine, South Australia. Mines and Energy South Australia, Adelaide.

Haren, R. et al. (1995): "The Broken Hill Exploration Initiative: seeking renewed prosperity in an historically prospective area of New South Wales and South Australia". AGSO Research Newsletter, 23, 15-16.

Hextall, B. (1995): "Victorian gold back in favour after Bendigo mineral finding". Sydney Morning Herald, September 25.

McGowan, B. (1994): Lost Mines. Barry McGowan, Canberra.

Moffatt, G. (Editor)(1992): Jobson's Mining Yearbook 1992-93. Riddell Information Services Ltd., Sydney.

Oliver, J.G. & Townsend, I.J. (1993): Gemstones in Australia: a review of the industry and the first national assessment of gemstone resources. Australian Gemstone Industry Council/AGPS, Canberra.

Parbo, A. (1992): Down Under: mineral heritage in Australia. Monograph 18. Australian Institute of Mining and Metallurgy, Melbourne.

Shackleton, W.G. & Binnie, M.N. (1993): Exploring Australia's Mining Heritage: a visitor's guide. Osmond Earth Sciences, Kent Town, South Australia.

Wilkinson, D. (Editor)(1994): Register of Australian Mining 1994/95. Resource Information Unit Ltd., Subiaco.

 Table 1 Mining operations in the Murray-Darling Basin, by ASIC industry class, 1992-93 (source: Data provided by Australian Bureau of Statistics, Canberra)

N.B.: Sales of goods and services includes revenue from sale of minerals (net of coal export levy and petroleum production excise duty) and other goods (e.g. minerals bought for re-sale, waste materials) and service income (e.g. repair and service income, contract, sub-contract and commission income, installation charges).

ABS (1994): Mining Industry Australia 1992-93. Catalogue No. 8402.0. Australian Bureau of Statistics, Canberra.