World Mineral Production - NERC Open Research Archive - Natural ...

COPPER
Characteristics
Copper is a reddish, malleable and ductile metal valued for its
excellent thermal and electrical conductive properties and its
resistance to corrosion. Copper combines with a number of
elements to form a wide variety of copper minerals and ores.
More than 150 copper-bearing minerals have been identified
although only a small number of these, chief of which is
chalcopyrite (CuFeS2), are of economic importance. The upper
parts of orebodies often also contain ‘oxide’ ore minerals such
as malachite and chrysocolla. These are underlain by a layer of
‘sulphide enrichment’ characterised by the sulphide mineral,
chalcocite. Types of copper orebody include: ‘porphyries’,
typical of North and South America, where disseminated
copper minerals are associated with igneous intrusions;
stratabound orebodies where the copper occurs in sedimentary
rocks; and volcanic-hosted massive sulphide (VMS) deposits,
in which copper is associated with other base metal sulphides
such as lead and zinc. The largest reserves are in Chile (150
million tonnes), Indonesia and USA (35 million tonnes each),
Mexico, Peru and Poland (30 million tonnes each); (Edelstein
2008).
Uses
The ability to conduct electricity and heat are two of the most
important properties of copper, since about 40 per cent (in
Europe) of all copper produced is used in electrical and
electronic applications (International Copper Study Group,
2007). When alloyed with other metals it acquires additional
properties including: increased hardness, tensile strength, and
improved corrosion resistance. Brass and bronze are two of the
most important alloys of copper. Coppers malleability and
ease of use in machines during the fabrication process allows
for a high production rate of accurate copper shapes for a
relatively lower cost than that of its substitutes. Copper is a
major industrial metal, due to its beneficial properties
discussed here, ranking third after iron and aluminium in terms
of quantity consumed.
Statistics for the final applications of copper products vary
widely: in the USA the dominant sector is ‘construction’ (50
per cent), in Europe it is ‘transport’ (41 per cent) and in Asia
‘electrical’ (33 per cent) (International Copper Study Group,
2007). These differences are at least partly caused by differing
statistical methodologies. The chief immediate use of copper is
in electrical circuits, wiring and cables, regardless of the final
application. Copper is used in many forms in buildings
including wire, plumbing pipes and fittings, electrical outlets,
switches, and locks. Construction of an average modern house
requires at least 200 kg of copper metal. Copper roofing is
highly rated for its corrosion resistance and architectural
characteristics. Copper is the best electrical conductor after
silver and is widely used in the production of energy-efficient
power circuits. Copper wire is extensively used in
telecommunications and is essential for computer networks.
World production in 2006
Copper is produced in about fifty countries. Eight countries
account for about 80 per cent of world mine production. Each
of these eight countries produce over 500 000 tonnes of
copper per year.
In the last 20 years, copper production has almost doubled
from 8.4 million tonnes in 1985 to more than 15 million
tonnes in 2006. This sustained rise can be attributed to the
steady increase in copper demand from growing economies
around the world. The proportion of copper mined in South
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America has increased from about one-quarter to nearly onehalf
of total world production. This is largely due to an
increase in production from Chile, from 16 per cent of world
production in 1985 to 35 per cent in 2006. Total production
from North and Central America has not increased
significantly, despite a 55 per cent rise in Mexican output.
The contribution from Asia has been increasing and. Africa’s
copper production has also risen in recent years driven by
Zambia and the Democratic Republic of Congo (DRC).
Zambia’s mine production has increased by 63 per cent from
307 834 tonnes in 2002 to 502 000 tonnes in 2006. The DRC
copper production has risen rapidly during the last five years
as stability returns to the country, following five years of war.
DRC, which has the potential to become an extremely
significant copper producer, increased copper production from
28 000 tonnes in 2002 to 131 400 tonnes in 2006.
Rising demand for copper has meant that many mines are now
operating at almost full capacity. Smelter and refinery
capacities are becoming a bottleneck to production. This
coupled with limited expansion potential and diminishing ore
reserves of existing mines, means that production is likely to
level off unless the current high copper prices are reinvested
into exploration and future production infrastructure. Copper
mine production depends on a relatively small number of large
production units. It is therefore vulnerable to disruptions
caused by strikes, natural disasters and concerns over supplies
of natural gas and water. Improved mining and extraction
techniques now allow copper from low grade ores, that were
previously considered as waste, to be extracted using chemical
and bio-leaching techniques. However, in many cases the
leach cycle may be measured in years, resulting in a
considerable lag time in copper metal production by these
methods.
Total world copper mine production in 2006 was 15 million
tonnes. Chile is the largest copper-producing country, with an
output of 5.4 million tonnes in 2006. Total world production
of smelter copper was 11.8 million tonnes in 2006, with Asia
contributing 44 per cent of the world total. During the last 10–
15 years mine production statistics have become decoupled
from total smelter production, whereas prior to 1990 the two
correlated very well. This statistical divergence is explained by
the increasing use of chemical extraction techniques which
compete with conventional smelter production. Total world
refined copper production was 17.2 million tonnes in 2006,
from over 45 countries. The difference between mine and
refinery production is attributed to the contribution of
secondary refined (scrap) copper to the total. Recycling of old
scrap provides about 20 per cent of annual copper
consumption.
Prices
The price paid for copper on the metal exchanges primarily
reflects global balances of copper supply and demand, but may
be significantly affected by speculative activity, currency
exchange rates and market news. Copper demand and price
typically reflect global economic cycles, and as a result the
copper price has historically experienced major fluctuations.
All copper prices quoted are based on the London Metal
Exchange (LME) cash daily official price, in US dollars per
tonne, as quoted by Metal Bulletin.
The copper market was exceptionally strong during 2006 with
copper prices averaging US$6700 tonne over the whole year,
an 83 per cent increase over 2005. During the first five months
of 2006, copper prices continued their upward trend and in