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Copper is a ductile metal with excellent electrical conductivity, and finds extensive use as an electrical conductor, heat conductor, as a building material, and as a component of various alloys.
Copper is an essential trace nutrient to all high plants and animals. In animals, including humans, it is found primarily in the bloodstream, as a co-factor in various enzymes, and in copper-based pigments. However, in sufficient amounts, copper can be poisonous and even fatal to organisms.
Copper has played a significant part in the history of humankind, which has used the easily accessible uncompounded metal for thousands of years. Several early civilizations have early evidence of using copper. During the Roman Empire, copper was principally mined on Cyprus, hence the origin of the name of the metal as Cyprium, "metal of Cyprus", later shortened to Cuprum.
A number of countries, such as Chile and the United States, still have sizable reserves of the metal which are extracted through large open pit mines, however like tin there may be insufficient reserves to sustain current rates of consumption. High demand relative to supply has caused a price spike in the 2000s
There are two stable isotopes, 63Cu and 65Cu, along with a couple dozen radioisotopes. The vast majority of radioisotopes have half lives on the order of minutes or less; the longest lived, 67Cu, has a half life of 61.8 hours. See also isotopes of copper.
Copper just above its melting point keeps its pink luster color when enough light outshines the orange incandescence color.
Copper exists as a metallically bonded substance, allowing it to have a wide variety of metallic properties.
Copper has a high electrical and thermal conductivity, second only to silver among pure metals at room temperature.
Copper is a reddish-colored metal; it has its characteristic color because of its band structure. In its liquefied state, a pure copper surface without ambient light appears somewhat greenish, a characteristic shared with gold. When liquid copper is in bright ambient light, it retains some of its pinkish luster.
Copper occupies the same family of the periodic table as silver and gold, since they each have one s-orbital electron on top of a filled electron shell. This similarity in electron structure makes them similar in many characteristics. All have very high thermal and electrical conductivity, and all are malleable metals.
A single crystal copper consists of a few micrometres of small crystals. In this form of crystal (c), the yield stress is high and crystal undergoes a large amount of elastic deformation before going into the plastic deformation region. The plastic deformation region has an unpredictable outcome. The stress level decreases significantly as necking begins to occur.
Polycrystal copper has many crystal of different geometries combined. The plastic deformation of polycrystal is similar to mild steel. Copper has a high ductility and will continue to elongate as stress is applied. It is very useful in copper wire drawing.
Numerous copper alloys exist, many with important historical and contemporary uses. Speculum metal and bronze are alloys of copper and tin. Brass is an alloy of copper and zinc. Monel metal, also called cupronickel, is an alloy of copper and nickel. While the metal "bronze" usually refers to copper-tin alloys, it also is a generic term for any alloy of copper, such as aluminium bronze, silicon bronze, and manganese bronze.
Copper output in 2005
World production trend
Current price is at least four times higher than the 2002 value.
In 2005, Chile was the top mine producer of copper with at least one-third world share followed by the USA, Indonesia and Peru, reports the British Geological Survey.
Most copper ore is mined or extracted as copper sulfides from large open pit mines in porphyry copper deposits that contain 0.4 to 1.0 percent copper. Examples include: Chuquicamata in Chile and El Chino Mine in New Mexico. The average abundance of copper found within crustal rocks is approximately 68 ppm by mass, and 22 ppm by atoms.
The Intergovernmental Council of Copper Exporting Countries (CIPEC), defunct since 1992, once tried to play a similar role for copper as OPEC does for oil, but never achieved the same influence, not least because the second-largest producer, the United States, was never a member. Formed in 1967, its principal members were Chile, Peru, Zaire, and Zambia.
The copper price has quintupled from the 60-year low in 1999, rising from US$0.60 per pound (US$1.32/kg) in June 1999 to US$3.75 per pound (US$8.27/kg) in May 2006, where it dropped to US$2.40 (US$5.29/kg) in February 2007 then rebounded to US$3.50 (US$7.71/kg = £3.89 = €5.00) in April 2007.
The Earth has an estimated 61 years of copper reserves remaining. Environmental analyst, Lester Brown, however, has suggested copper might run out within 25 years based on a reasonable extrapolation of 2% growth per year.
Copper is malleable and ductile, a good conductor of heat and, when very pure, a good conductor of electricity.
It is used extensively, in products such as:
- Copper piping system with intumescent firestop being installed by an insulator in Vancouver, Canada.
- Electronics; Copper wire,Electromagnets,Printed circuit boards. ,Lead free solder, alloyed with tin. Electrical machines, especially electromagnetic motors, generators and transformers. Electrical relays, electrical busbars and electrical switches. Vacuum tubes, cathode ray tubes, and the magnetrons in microwave ovens. Wave guides for microwave radiation. Integrated circuits, increasingly replacing aluminium because of its superior electrical conductivity. As a material in the manufacture of computer heat sinks, as a result of its superior heat dissipation capacity to aluminium.
- Architecture / Industry; Copper has been used as water-proof roofing material since ancient times, giving many old buildings their greenish roofs and domes. Initially copper oxide forms, replaced by cuprous and cupric sulfide, and finally by copper carbonate. The final carbonate patina is highly resistant to corrosion.
Statuary: The Statue of Liberty, for example, contains 179,220 pounds (81.3 tonnes) of copper. Alloyed with nickel, e.g. cupronickel and Monel, used as corrosive assistant materials in shipbuilding.
Watt's steam engine firebox due to superior heat dissipation.
Copper nails were used in making oast cowls.
- Household products; Copper plumbing fittings and compression tubes., Doorknobs and other fixtures in houses., Roofing, guttering, and rainspouts on buildings., In cookware, such as frying pans. Most flatware (knives, forks, spoons) contains some copper (nickel silver)., Sterling silver, if it is to be used in dinnerware, must contain a few percent copper. ,Copper water heating cylinders ,Copper Range Hoods , Copper Bath Tubs ,Copper Counters ,Copper Sinks
- Coinage; As a component of coins, often as cupronickel alloy. Coins in the following countries all contain copper: European Union (Euro), United States, United Kingdom (sterling), Australia and New Zealand.
- Biomedical applications As a biostatic surface in hospitals, and to line parts of ships to protect against barnacles and mussels, originally used pure, but superseded by Muntz Metal. Bacteria will not grow on a copper surface because it is biostatic. Copper doorknobs are used by hospitals to reduce the transfer of disease, and Legionnaires' disease is suppressed by copper tubing in air-conditioning systems.
Copper(II) sulfate is used as a fungicide and as algae control in domestic lakes and ponds. It is used in gardening powders and sprays to kill mildew.
Copper-62-PTSM, a complex containing radioactive copper-62, is used as a Positron emission tomography radiotracer for heart blood flow measurements.
Copper-64 can be used as a Positron emission tomography radiotracer for medical imaging. When complexed with a chelate it can be used to treat cancer through radiation therapy.
- Chemical applications Compounds, such as Fehling's solution, have applications in chemistry. As a component in ceramic glazes, and to color glass.
- Other Musical instruments, especially brass instruments and cymbals. Class D Fire Extinguisher, used in powder form to extinguish lithium fires by covering the burning metal and performing similar to a heat sink.
- Textile fibers to create antimicrobial protective fabrics.
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