Copper

Copper (Cu) is a ductile, coloured metal that has very high thermal and electrical conductivity. It was the first metal to be used by man (probably as early as 7000 BC) and was used as a substitute for stone; its malleability enabled tools to be easily shaped by beating. In the modern era, the growth of the copper industry has been intimately linked with the increasing use of electricity owing to two of its properties: copper is an excellent electrical conductor and is ductile enough to be drawn into wire and beaten into sheets without fracturing. It is therefore used to produce electrical cables and electrical equipment. Copper and its alloys are also widely used in plumbing components, building construction as well as industrial machinery and equipment. An average car contains more than 20 kg of copper and suburban homes have around 200 kg of copper.

The main ore mineral of copper in Australia (and worldwide) is chalcopyrite (CuFeS2). Bornite (Cu5FeS4), covellite (CuS) and chalcocite (Cu2S) are also important sources around the world and, in addition, many ore bodies contain some malachite (CuCO3.Cu(OH)2), azurite (Cu3(CO3)2.Cu(OH)2), cuprite (Cu2O), tenorite (CuO) and native copper. Copper is widely distributed in Australian rocks of Precambrian and Paleozoic age (more than 250 million years old). Most copper is mined or extracted as copper sulphides from large open-pit mines in porphyry copper deposits, but it is also found within many other types of deposits, including iron-oxide-copper-gold orebodies and sediment-hosted copper deposits.

Australia is one of the world's top copper producers with substantial resources located in all states and the Northern Territory (Figure 3.9). However, Australia's main resources of copper are largely at the Olympic Dam copper-uranium-gold deposit in South Australia and the Mount Isa copper-lead-zinc deposit in Queensland and these states contain the largest percentages of both EDR and total resources of copper (Figure 3.10). Other significant copper producing operations are at Prominent Hill in South Australia; Northparkes, Cadia-Ridgeway, Cobar and Tritton in New South Wales; Ernest Henry in Queensland; Nifty, Boddington, Telfer, DeGrussa and Golden Grove in Western Australia; and Mount Lyell in Tasmania.

Most of the copper ore produced in Australia comes from underground mines. At some Australian mines, the copper is leached from the ore to produce a copper-rich solution that is later treated to recover the copper metal. The traditional method used at most mines involves the ore being broken and brought to the surface for crushing. The ore is then ground finely before the copper-bearing sulphide minerals are concentrated by a flotation process that separates the grains of ore mineral from the gangue (waste material). Depending on the type of copper -bearing minerals in the ore and the treatment processes used, the concentrate can contain between 25 and 57% copper. The concentrate is then processed in a smelter.

Figure 3.9 is a map of Australia showing the names, locations and size of major copper deposits. The map also shows the state boundaries and capital cities as well as the major geological provinces of the country. Copper deposits are displayed as filled green circles split into five sizes according to the total in situ resources of copper. The five sizes are labelled '<0.5 million tonnes', '0.5 to 1 million tonnes', '1 to 5 million tonnes', '5 to 10 million tonnes' and 'greater than 50 million tonnes'. In addition, some circles are drawn with a heavy black line indicating that these deposits are operating mines. The map shows the greatest concentrations of significant copper deposits in Australia occur in Queensland around Mount Isa, in New South Wales around Bathurst and in South Australia around Olympic Dam. Copper deposits are also scattered across Western Australia and a single deposit occurs in Tasmania at Mount Lyell. The New South Wales deposits are hosted in Ordovician rocks but all others are hosted by Archean or Proterozoic lithologies

Figure 3.9 Australia's major copper deposits based on total Identified Resources.
Source: Geoscience Australia.

Resources and Reserves

Table 3.13 Australia's resources of copper and world figures as at December 2012.
Units JORC Reserves (% of EDR) Economic Demonstrated Resources (EDR) Paramarginal Demonstrated Resources Submarginal Demonstrated Resources Inferred Resources Accessible EDR Mine Production in 2012 World Economic Resources World Mine Production in 2012
Source: Geoscience Australia, the Bureau of Resources and Energy Economics and the United States Geological Survey; Paramarginal and submarginal demonstrated resources are subeconomic at this time; Mt = million tonnes.
Mt 25.2 (28%) 91.1 1.4 0.4 43.9 91.1 0.91 690 16.6

Figure 3.10 comprises two pie charts side by side. The one on the left shows the percentage of Economic Demonstrated Resources (EDR) of copper held by each state and territory in Australia as at December 2012. The chart on the right shows the percentage of total copper resources held by each state and territory in Australia as at December 2012. South Australia has the most copper EDR with 69% followed by New South Wales with 13%, Queensland with 12% and Western Australia with 5%. Similarly, South Australia has the greatest total copper resources with66% followed by Queensland with 14%, New South Wales with 12% and Western Australia with 6%.

Figure 3.10 Percentages of Economic Demonstrated Resources and total resources of copper held by the states and territories in Australia. Total resources comprise all Demonstrated and Inferred Resources. Numbers are rounded so might not add up to 100% exactly.
Source: Geoscience Australia.

World Ranking

Table 3.14 World economic resources for copper.
Rank Country Copper (Mt) Percentage (%)
Source: United States Geological Survey and Geoscience Australia; Mt = million tonnes; Percentages are rounded so might not add up to 100% exactly.
1 Chile 190 28%
2 Australia 91 13%
3 Peru 76 11%
4 United States of America 39 6%
5 Mexico 38 6%
6 China 30 4%
7 Russia 30 4%
8 Indonesia 28 4%
9 Poland 26 4%
10 Zambia 20 3%
  Others 117 17%
  Total 685  
Table 3.15 World production for copper
Rank Country Copper (Mt) Percentage (%)
Source: United States Geological Survey and the Bureau of Resources and Energy Economics; Mt = million tonnes; Percentages are rounded so might not add up to 100% exactly.
1 Chile 5.37 31%
2 China 1.50 9%
3 Peru 1.24 7%
4 United States of America 1.15 7%
5 Australia 0.91 5%
6 Russia 0.72 4%
7 Zambia 0.68 4%
8 Congo 0.58 3%
9 Canada 0.53 3%
10 Mexico 0.50 3%
  Others 3.92 23%
  Total 17.10  

Trends

Following the adoption of the JORC Code by the Australian mining industry, many companies first used this code in 1989 for reporting their copper resources. These companies re-estimated mineral resources to comply with the JORC Code which resulted in a sharp fall in Australia's copper EDR in 1989 ('a' in Figure 3.11).

The sharp increase in copper EDR in 1993 ('b' Figure 3.11) resulted mainly from an increase in company-announced resources for the Olympic Dam deposit in South Australia. Additional resources were also reported for Ernest Henry in Queensland, Northparkes in New South Wales and other smaller deposits.

Reassessments of copper resources by Geoscience Australia in 2002 and 2003 resulted in further transfers (reclassification) of Olympic Dam resources into EDR ('c' in Figure 3.11). In 2007 and 2008, copper resources again increased sharply, mainly because of Olympic Dam where drilling outlined large resources in the south-eastern part of the deposit ('d' in Figure 3.11).

Figure 3.11 shows the Economic Demonstrated Resources (EDR) of copper from 1975 to 2012. There is one line on the graph. The vertical axis is labelled in millions of tonnes beginning at 0 and in increments of 10 million. The horizontal axis is labelled with the year starting with 1975 and ending with 2012. In the graph, the line begins at 5.9 million tonnes in 1975 and ranges between 5.5 and 6 million tonnes until 1983. From 1984, copper EDR increased rapidly to a peak of 17 million tonnes in 1988. Copper EDR plummeted in 1989 to 6.7 million tonnes and has since risen in a stepwise fashion to 91.1million tonnes in 2012.

Figure 3.11 Trends in Economic Demonstrated Resources for copper since 1975.
Source: Geoscience Australia.

Resource to Production Ratio

Table 3.16 Indicative years of copper resources (rounded to the nearest 5 years) as a ratio of Accessible Economic Demonstrated Resources divided by the production rate for each year.
Year 1998 2003 2008 2009 2010 2011 2012
Source: Geoscience Australia.
AEDR/Production 40 50 85 95 100 90 100