Copper is a chemical element with the symbol Cu (from Latin: cuprum) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkish-orange color. Copper is used as a conductor of heat and electricity, as a building material, and as a constituent of various metal alloys, such as sterling silver used in jewelry, cupronickel used to make marine hardware and coins, and constantan used in strain gauges and thermocouples for temperature measurement.
|Appearance||red-orange metallic luster|
|Standard atomic weight Ar, std(Cu)||63.546(3)|
|Copper in the periodic table|
|Atomic number (Z)||29|
|Element category||Transition metal|
|Electron configuration||[Ar] 3d10 4s1|
Electrons per shell
|2, 8, 18, 1|
|Phase at STP||solid|
|Melting point||1357.77 K (1084.62 °C, 1984.32 °F)|
|Boiling point||2835 K (2562 °C, 4643 °F)|
|Density (near r.t.)||8.96 g/cm3|
|when liquid (at m.p.)||8.02 g/cm3|
|Heat of fusion||13.26 kJ/mol|
|Heat of vaporization||300.4 kJ/mol|
|Molar heat capacity||24.440 J/(mol·K)|
|Oxidation states||−2, +1, +2, +3, +4 (a mildly basic oxide)|
|Electronegativity||Pauling scale: 1.90|
|Atomic radius||empirical: 128 pm|
|Covalent radius||132±4 pm|
|Van der Waals radius||140 pm|
|Spectral lines of copper|
|Crystal structure||face-centered cubic (fcc)|
|Speed of sound thin rod||(annealed)|
3810 m/s (at r.t.)
|Thermal expansion||16.5 µm/(m·K) (at 25 °C)|
|Thermal conductivity||401 W/(m·K)|
|Electrical resistivity||16.78 nΩ·m (at 20 °C)|
|Magnetic susceptibility||−5.46·10−6 cm3/mol|
|Young's modulus||110–128 GPa|
|Shear modulus||48 GPa|
|Bulk modulus||140 GPa|
|Vickers hardness||343–369 MPa|
|Brinell hardness||235–878 MPa|
|Naming||after Cyprus, principal mining place in Roman era (Cyprium)|
|Discovery||Middle East (9000 BC)|
|Main isotopes of copper|
Copper is one of the few metals that can occur in nature in a directly usable metallic form (native metals). This led to very early human use in several regions, from c. 8000 BC. Thousands of years later, it was the first metal to be smelted from sulfide ores, c. 5000 BC, the first metal to be cast into a shape in a mold, c. 4000 BC and the first metal to be purposefully alloyed with another metal, tin, to create bronze, c. 3500 BC.
In the Roman era, copper was principally mined on Cyprus, the origin of the name of the metal, from aes сyprium (metal of Cyprus), later corrupted to сuprum (Latin), from which the words derived, coper (Old English) and copper, first used around 1530.
The commonly encountered compounds are copper(II) salts, which often impart blue or green colors to such minerals as azurite, malachite, and turquoise, and have been used widely and historically as pigments.
Copper used in buildings, usually for roofing, oxidizes to form a green verdigris (or patina). Copper is sometimes used in decorative art, both in its elemental metal form and in compounds as pigments. Copper compounds are used as bacteriostatic agents, fungicides, and wood preservatives.
Copper is essential to all living organisms as a trace dietary mineral because it is a key constituent of the respiratory enzyme complex cytochrome c oxidase. In molluscs and crustaceans, copper is a constituent of the blood pigment hemocyanin, replaced by the iron-complexed hemoglobin in fish and other vertebrates. In humans, copper is found mainly in the liver, muscle, and bone. The adult body contains between 1.4 and 2.1 mg of copper per kilogram of body weight.
Copper, silver, and gold are in group 11 of the periodic table; these three metals have one s-orbital electron on top of a filled d-electron shell and are characterized by high ductility, and electrical and thermal conductivity. The filled d-shells in these elements contribute little to interatomic interactions, which are dominated by the s-electrons through metallic bonds. Unlike metals with incomplete d-shells, metallic bonds in copper are lacking a covalent character and are relatively weak. This observation explains the low hardness and high ductility of single crystals of copper. At the macroscopic scale, introduction of extended defects to the crystal lattice, such as grain boundaries, hinders flow of the material under applied stress, thereby increasing its hardness. For this reason, copper is usually supplied in a fine-grained polycrystalline form, which has greater strength than monocrystalline forms.
The softness of copper partly explains its high electrical conductivity (59.6×106 S/m) and high thermal conductivity, second highest (second only to silver) among pure metals at room temperature. This is because the resistivity to electron transport in metals at room temperature originates primarily from scattering of electrons on thermal vibrations of the lattice, which are relatively weak in a soft metal. The maximum permissible current density of copper in open air is approximately 3.1×106 A/m2 of cross-sectional area, above which it begins to heat excessively.
Copper is one of a few metallic elements with a natural color other than gray or silver. Pure copper is orange-red and acquires a reddish tarnish when exposed to air. The characteristic color of copper results from the electronic transitions between the filled 3d and half-empty 4s atomic shells – the energy difference between these shells corresponds to orange light.
Copper does not react with water, but it does slowly react with atmospheric oxygen to form a layer of brown-black copper oxide which, unlike the rust that forms on iron in moist air, protects the underlying metal from further corrosion (passivation). A green layer of verdigris (copper carbonate) can often be seen on old copper structures, such as the roofing of many older buildings and the Statue of Liberty. Copper tarnishes when exposed to some sulfur compounds, with which it reacts to form various copper sulfides.
There are 29 isotopes of copper. 63Cu and 65Cu are stable, with 63Cu comprising approximately 69% of naturally occurring copper; both have a spin of 3⁄2. The other isotopes are radioactive, with the most stable being 67Cu with a half-life of 61.83 hours. Seven metastable isotopes have been characterized; 68mCu is the longest-lived with a half-life of 3.8 minutes. Isotopes with a mass number above 64 decay by β−, whereas those with a mass number below 64 decay by β+. 64Cu, which has a half-life of 12.7 hours, decays both ways.
Copper is produced in massive stars and is present in the Earth's crust in a proportion of about 50 parts per million (ppm). In nature, copper occurs in a variety of minerals, including native copper, copper sulfides such as chalcopyrite, bornite, digenite, covellite, and chalcocite, copper sulfosalts such as tetrahedite-tennantite, and enargite, copper carbonates such as azurite and malachite, and as copper(I) or copper(II) oxides such as cuprite and tenorite, respectively. The largest mass of elemental copper discovered weighed 420 tonnes and was found in 1857 on the Keweenaw Peninsula in Michigan, US. Native copper is a polycrystal, with the largest single crystal ever described measuring 4.4×3.2×3.2 cm.
Most copper is mined or extracted as copper sulfides from large open pit mines in porphyry copper deposits that contain 0.4 to 1.0% copper. Sites include Chuquicamata, in Chile, Bingham Canyon Mine, in Utah, United States, and El Chino Mine, in New Mexico, United States. According to the British Geological Survey, in 2005, Chile was the top producer of copper with at least one-third of the world share followed by the United States, Indonesia and Peru. Copper can also be recovered through the in-situ leach process. Several sites in the state of Arizona are considered prime candidates for this method. The amount of copper in use is increasing and the quantity available is barely sufficient to allow all countries to reach developed world levels of usage.
Copper has been in use at least 10,000 years, but more than 95% of all copper ever mined and smelted has been extracted since 1900, and more than half was extracted the last 24 years. As with many natural resources, the total amount of copper on Earth is vast, with around 1014 tons in the top kilometer of Earth's crust, which is about 5 million years' worth at the current rate of extraction. However, only a tiny fraction of these reserves is economically viable with present-day prices and technologies. Estimates of copper reserves available for mining vary from 25 to 60 years, depending on core assumptions such as the growth rate. Recycling is a major source of copper in the modern world. Because of these and other factors, the future of copper production and supply is the subject of much debate, including the concept of peak copper, analogous to peak oil.
The price of copper has historically been unstable, and its price increased from the 60-year low of US$0.60/lb (US$1.32/kg) in June 1999 to $3.75 per pound ($8.27/kg) in May 2006. It dropped to $2.40/lb ($5.29/kg) in February 2007, then rebounded to $3.50/lb ($7.71/kg) in April 2007.[better source needed] In February 2009, weakening global demand and a steep fall in commodity prices since the previous year's highs left copper prices at $1.51/lb ($3.32/kg).
The concentration of copper in ores averages only 0.6%, and most commercial ores are sulfides, especially chalcopyrite (CuFeS2), bornite (Cu5FeS4) and, to a lesser extent, covellite (CuS) and chalcocite (Cu2S). These minerals are concentrated from crushed ores to the level of 10–15% copper by froth flotation or bioleaching. Heating this material with silica in flash smelting removes much of the iron as slag. The process exploits the greater ease of converting iron sulfides into oxides, which in turn react with the silica to form the silicate slag that floats on top of the heated mass. The resulting copper matte, consisting of Cu2S, is roasted to convert all sulfides into oxides:
- 2 Cu2S + 3 O2 → 2 Cu2O + 2 SO2
The cuprous oxide is converted to blister copper upon heating:
- 2 Cu2O → 4 Cu + O2
The Sudbury matte process converted only half the sulfide to oxide and then used this oxide to remove the rest of the sulfur as oxide. It was then electrolytically refined and the anode mud exploited for the platinum and gold it contained. This step exploits the relatively easy reduction of copper oxides to copper metal. Natural gas is blown across the blister to remove most of the remaining oxygen and electrorefining is performed on the resulting material to produce pure copper:
- Cu2+ + 2 e− → Cu
Like aluminium, copper is recyclable without any loss of quality, both from raw state and from manufactured products. In volume, copper is the third most recycled metal after iron and aluminium. An estimated 80% of all copper ever mined is still in use today. According to the International Resource Panel's Metal Stocks in Society report, the global per capita stock of copper in use in society is 35–55 kg. Much of this is in more-developed countries (140–300 kg per capita) rather than less-developed countries (30–40 kg per capita).
The process of recycling copper is roughly the same as is used to extract copper but requires fewer steps. High-purity scrap copper is melted in a furnace and then reduced and cast into billets and ingots; lower-purity scrap is refined by electroplating in a bath of sulfuric acid.
Numerous copper alloys have been formulated, many with important uses. Brass is an alloy of copper and zinc. Bronze usually refers to copper-tin alloys, but can refer to any alloy of copper such as aluminium bronze. Copper is one of the most important constituents of silver and karat gold solders used in the jewelry industry, modifying the color, hardness and melting point of the resulting alloys. Some lead-free solders consist of tin alloyed with a small proportion of copper and other metals.
The alloy of copper and nickel, called cupronickel, is used in low-denomination coins, often for the outer cladding. The US five-cent coin (currently called a nickel) consists of 75% copper and 25% nickel in homogeneous composition. Prior to the introduction of cupronickel, which was widely adopted by countries in the latter half of the 20th century, alloys of copper and silver were also used, with the United States using an alloy of 90% silver and 10% copper until 1965, when circulating silver was removed from all coins with the exception of the Half dollar - these were debased to an alloy of 40% silver and 60% copper between 1965 and 1970. The alloy of 90% copper and 10% nickel, remarkable for its resistance to corrosion, is used for various objects exposed to seawater, though it is vulnerable to the sulfides sometimes found in polluted harbors and estuaries. Alloys of copper with aluminium (about 7%) have a golden color and are used in decorations. Shakudō is a Japanese decorative alloy of copper containing a low percentage of gold, typically 4–10%, that can be patinated to a dark blue or black color.
Copper forms a rich variety of compounds, usually with oxidation states +1 and +2, which are often called cuprous and cupric, respectively. Copper compounds, whether organic complexes or organometallics, promote or catalyse numerous chemical and biological processes.
As with other elements, the simplest compounds of copper are binary compounds, i.e. those containing only two elements, the principal examples being oxides, sulfides, and halides. Both cuprous and cupric oxides are known. Among the numerous copper sulfides, important examples include copper(I) sulfide and copper(II) sulfide.
Cuprous halides (with chlorine, bromine, and iodine) are known, as are cupric halides with fluorine, chlorine, and bromine. Attempts to prepare copper(II) iodide yield only cuprous iodide and iodine.
- 2 Cu2+ + 4 I− → 2 CuI + I2
Copper forms coordination complexes with ligands. In aqueous solution, copper(II) exists as [Cu(H2O)6]2+. This complex exhibits the fastest water exchange rate (speed of water ligands attaching and detaching) for any transition metal aquo complex. Adding aqueous sodium hydroxide causes the precipitation of light blue solid copper(II) hydroxide. A simplified equation is:
- Cu2+ + 2 OH− → Cu(OH)2
- Cu(H2O)4(OH)2 + 4 NH3 → [Cu(H2O)2(NH3)4]2+ + 2 H2O + 2 OH−
Many other oxyanions form complexes; these include copper(II) acetate, copper(II) nitrate, and copper(II) carbonate. Copper(II) sulfate forms a blue crystalline pentahydrate, the most familiar copper compound in the laboratory. It is used in a fungicide called the Bordeaux mixture.
Polyols, compounds containing more than one alcohol functional group, generally interact with cupric salts. For example, copper salts are used to test for reducing sugars. Specifically, using Benedict's reagent and Fehling's solution the presence of the sugar is signaled by a color change from blue Cu(II) to reddish copper(I) oxide. Schweizer's reagent and related complexes with ethylenediamine and other amines dissolve cellulose. Amino acids form very stable chelate complexes with copper(II). Many wet-chemical tests for copper ions exist, one involving potassium ferrocyanide, which gives a brown precipitate with copper(II) salts.
Compounds that contain a carbon-copper bond are known as organocopper compounds. They are very reactive towards oxygen to form copper(I) oxide and have many uses in chemistry. They are synthesized by treating copper(I) compounds with Grignard reagents, terminal alkynes or organolithium reagents; in particular, the last reaction described produces a Gilman reagent. These can undergo substitution with alkyl halides to form coupling products; as such, they are important in the field of organic synthesis. Copper(I) acetylide is highly shock-sensitive but is an intermediate in reactions such as the Cadiot-Chodkiewicz coupling and the Sonogashira coupling. Conjugate addition to enones and carbocupration of alkynes can also be achieved with organocopper compounds. Copper(I) forms a variety of weak complexes with alkenes and carbon monoxide, especially in the presence of amine ligands.
Copper(III) and copper(IV)
Copper(III) is most often found in oxides. A simple example is potassium cuprate, KCuO2, a blue-black solid. The most extensively studied copper(III) compounds are the cuprate superconductors. Yttrium barium copper oxide (YBa2Cu3O7) consists of both Cu(II) and Cu(III) centres. Like oxide, fluoride is a highly basic anion and is known to stabilize metal ions in high oxidation states. Both copper(III) and even copper(IV) fluorides are known, K3CuF6 and Cs2CuF6, respectively.
A timeline of copper illustrates how the metal has advanced human civilization for the past 11,000 years.
Copper occurs naturally as native metallic copper and was known to some of the oldest civilizations on record. The history of copper use dates to 9000 BC in the Middle East; a copper pendant was found in northern Iraq that dates to 8700 BC. Evidence suggests that gold and meteoric iron (but not smelted iron) were the only metals used by humans before copper. The history of copper metallurgy is thought to follow this sequence: First, cold working of native copper, then annealing, smelting, and, finally, lost-wax casting. In southeastern Anatolia, all four of these techniques appear more or less simultaneously at the beginning of the Neolithic c. 7500 BC.
Copper smelting was independently invented in different places. It was probably discovered in China before 2800 BC, in Central America around 600 AD, and in West Africa about the 9th or 10th century AD. Investment casting was invented in 4500–4000 BC in Southeast Asia and carbon dating has established mining at Alderley Edge in Cheshire, UK, at 2280 to 1890 BC. Ötzi the Iceman, a male dated from 3300–3200 BC, was found with an axe with a copper head 99.7% pure; high levels of arsenic in his hair suggest an involvement in copper smelting. Experience with copper has assisted the development of other metals; in particular, copper smelting led to the discovery of iron smelting. Production in the Old Copper Complex in Michigan and Wisconsin is dated between 6000 and 3000 BC. Natural bronze, a type of copper made from ores rich in silicon, arsenic, and (rarely) tin, came into general use in the Balkans around 5500 BC.
Alloying copper with tin to make bronze was first practiced about 4000 years after the discovery of copper smelting, and about 2000 years after "natural bronze" had come into general use. Bronze artifacts from the Vinča culture date to 4500 BC. Sumerian and Egyptian artifacts of copper and bronze alloys date to 3000 BC. The Bronze Age began in Southeastern Europe around 3700–3300 BC, in Northwestern Europe about 2500 BC. It ended with the beginning of the Iron Age, 2000–1000 BC in the Near East, and 600 BC in Northern Europe. The transition between the Neolithic period and the Bronze Age was formerly termed the Chalcolithic period (copper-stone), when copper tools were used with stone tools. The term has gradually fallen out of favor because in some parts of the world, the Chalcolithic and Neolithic are coterminous at both ends. Brass, an alloy of copper and zinc, is of much more recent origin. It was known to the Greeks, but became a significant supplement to bronze during the Roman Empire.
Ancient and Post-classical
In Greece, copper was known by the name chalkos (χαλκός). It was an important resource for the Romans, Greeks and other ancient peoples. In Roman times, it was known as aes Cyprium, aes being the generic Latin term for copper alloys and Cyprium from Cyprus, where much copper was mined. The phrase was simplified to cuprum, hence the English copper. Aphrodite (Venus in Rome) represented copper in mythology and alchemy because of its lustrous beauty and its ancient use in producing mirrors; Cyprus was sacred to the goddess. The seven heavenly bodies known to the ancients were associated with the seven metals known in antiquity, and Venus was assigned to copper.
Copper was first used in ancient Britain in about the 3rd or 2nd century BC. In North America, copper mining began with marginal workings by Native Americans. Native copper is known to have been extracted from sites on Isle Royale with primitive stone tools between 800 and 1600. Copper metallurgy was flourishing in South America, particularly in Peru around 1000 AD. Copper burial ornamentals from the 15th century have been uncovered, but the metal's commercial production did not start until the early 20th century.
The cultural role of copper has been important, particularly in currency. Romans in the 6th through 3rd centuries BC used copper lumps as money. At first, the copper itself was valued, but gradually the shape and look of the copper became more important. Julius Caesar had his own coins made from brass, while Octavianus Augustus Caesar's coins were made from Cu-Pb-Sn alloys. With an estimated annual output of around 15,000 t, Roman copper mining and smelting activities reached a scale unsurpassed until the time of the Industrial Revolution; the provinces most intensely mined were those of Hispania, Cyprus and in Central Europe.
The gates of the Temple of Jerusalem used Corinthian bronze treated with depletion gilding.[clarification needed] The process was most prevalent in Alexandria, where alchemy is thought to have begun. In ancient India, copper was used in the holistic medical science Ayurveda for surgical instruments and other medical equipment. Ancient Egyptians (~2400 BC) used copper for sterilizing wounds and drinking water, and later to treat headaches, burns, and itching.
The Great Copper Mountain was a mine in Falun, Sweden, that operated from the 10th century to 1992. It satisfied two thirds of Europe's copper consumption in the 17th century and helped fund many of Sweden's wars during that time. It was referred to as the nation's treasury; Sweden had a copper backed currency.
Copper is used in roofing, currency, and for photographic technology known as the daguerreotype. Copper was used in Renaissance sculpture, and was used to construct the Statue of Liberty; copper continues to be used in construction of various types. Copper plating and copper sheathing were widely used to protect the under-water hulls of ships, a technique pioneered by the British Admiralty in the 18th century. The Norddeutsche Affinerie in Hamburg was the first modern electroplating plant, starting its production in 1876. The German scientist Gottfried Osann invented powder metallurgy in 1830 while determining the metal's atomic mass; around then it was discovered that the amount and type of alloying element (e.g., tin) to copper would affect bell tones.
During the rise in demand for copper for the Age of Electricity, from the 1880s until the Great Depression of the 1930s, the United States produced one third to half the world's newly mined copper. Major districts included the Keweenaw district of northern Michigan, primarily native copper deposits, which was eclipsed by the vast sulphide deposits of Butte, Montana in the late 1880s, which itself was eclipsed by porphyry deposits of the Souhwest United States, especially at Bingham Canyon, Utah and Morenci, Arizona. Introduction of open pit steam shovel mining and innovations in smelting, refining, flotation concentration and other processing steps led to mass production. Early in the twentieth century, Arizona ranked first, followed by Montana, then Utah and Michigan.
The Intergovernmental Council of Copper Exporting Countries, formed in 1967 by Chile, Peru, Zaire and Zambia, operated in the copper market as OPEC does in oil, though it never achieved the same influence, particularly because the second-largest producer, the United States, was never a member; it was dissolved in 1988.
The major applications of copper are electrical wire (60%), roofing and plumbing (20%), and industrial machinery (15%). Copper is used mostly as a pure metal, but when greater hardness is required, it is put into such alloys as brass and bronze (5% of total use). For more than two centuries, copper paint has been used on boat hulls to control the growth of plants and shellfish. A small part of the copper supply is used for nutritional supplements and fungicides in agriculture. Machining of copper is possible, although alloys are preferred for good machinability in creating intricate parts.
Wire and cable
Despite competition from other materials, copper remains the preferred electrical conductor in nearly all categories of electrical wiring except overhead electric power transmission where aluminium is often preferred. Copper wire is used in power generation, power transmission, power distribution, telecommunications, electronics circuitry, and countless types of electrical equipment. Electrical wiring is the most important market for the copper industry. This includes structural power wiring, power distribution cable, appliance wire, communications cable, automotive wire and cable, and magnet wire. Roughly half of all copper mined is used for electrical wire and cable conductors. Many electrical devices rely on copper wiring because of its multitude of inherent beneficial properties, such as its high electrical conductivity, tensile strength, ductility, creep (deformation) resistance, corrosion resistance, low thermal expansion, high thermal conductivity, ease of soldering, malleability, and ease of installation.
For a short period from the late 1960s to the late 1970s, copper wiring was replaced by aluminium wiring in many housing construction projects in America. The new wiring was implicated in a number of house fires and the industry returned to copper.
Integrated circuits and printed circuit boards increasingly feature copper in place of aluminium because of its superior electrical conductivity; heat sinks and heat exchangers use copper because of its superior heat dissipation properties. Electromagnets, vacuum tubes, cathode ray tubes, and magnetrons in microwave ovens use copper, as do waveguides for microwave radiation.
Copper's superior conductivity enhances the efficiency of electrical motors. This is important because motors and motor-driven systems account for 43%–46% of all global electricity consumption and 69% of all electricity used by industry. Increasing the mass and cross section of copper in a coil increases the efficiency of the motor. Copper motor rotors, a new technology designed for motor applications where energy savings are prime design objectives, are enabling general-purpose induction motors to meet and exceed National Electrical Manufacturers Association (NEMA) premium efficiency standards.
Copper has been used since ancient times as a durable, corrosion resistant, and weatherproof architectural material. Roofs, flashings, rain gutters, downspouts, domes, spires, vaults, and doors have been made from copper for hundreds or thousands of years. Copper's architectural use has been expanded in modern times to include interior and exterior wall cladding, building expansion joints, radio frequency shielding, and antimicrobial and decorative indoor products such as attractive handrails, bathroom fixtures, and counter tops. Some of copper's other important benefits as an architectural material include low thermal movement, light weight, lightning protection, and recyclability
The metal's distinctive natural green patina has long been coveted by architects and designers. The final patina is a particularly durable layer that is highly resistant to atmospheric corrosion, thereby protecting the underlying metal against further weathering. It can be a mixture of carbonate and sulfate compounds in various amounts, depending upon environmental conditions such as sulfur-containing acid rain. Architectural copper and its alloys can also be 'finished' to take on a particular look, feel, or color. Finishes include mechanical surface treatments, chemical coloring, and coatings.
Copper is biostatic, meaning bacteria and many other forms of life will not grow on it. For this reason it has long been used to line parts of ships to protect against barnacles and mussels. It was originally used pure, but has since been superseded by Muntz metal and copper-based paint. Similarly, as discussed in copper alloys in aquaculture, copper alloys have become important netting materials in the aquaculture industry because they are antimicrobial and prevent biofouling, even in extreme conditions and have strong structural and corrosion-resistant properties in marine environments.
Copper-alloy touch surfaces have natural properties that destroy a wide range of microorganisms (e.g., E. coli O157:H7, methicillin-resistant Staphylococcus aureus (MRSA), Staphylococcus, Clostridium difficile, influenza A virus, adenovirus, and fungi). Some 355 copper alloys[clarification needed] were proven to kill more than 99.9% of disease-causing bacteria within just two hours when cleaned regularly. The United States Environmental Protection Agency (EPA) has approved the registrations of these copper alloys as "antimicrobial materials with public health benefits"; that approval allows manufacturers to make legal claims to the public health benefits of products made of registered alloys. In addition, the EPA has approved a long list of antimicrobial copper products made from these alloys, such as bedrails, handrails, over-bed tables, sinks, faucets, door knobs, toilet hardware, computer keyboards, health club equipment, and shopping cart handles (for a comprehensive list, see: Antimicrobial copper-alloy touch surfaces#Approved products). Copper doorknobs are used by hospitals to reduce the transfer of disease, and Legionnaires' disease is suppressed by copper tubing in plumbing systems. Antimicrobial copper alloy products are now being installed in healthcare facilities in the U.K., Ireland, Japan, Korea, France, Denmark, and Brazil and in the subway transit system in Santiago, Chile, where copper-zinc alloy handrails will be installed in some 30 stations between 2011 and 2014. Textile fibers can be blended with copper to create antimicrobial protective fabrics.
Copper may be used as a speculative investment due to the predicted increase in use from worldwide infrastructure growth, and the important role it has in producing wind turbines, solar panels, and other renewable energy sources . Another reason predicted demand increases is the fact that electric cars contain an average of 3.6 times as much copper as conventional cars, although the effect of electric cars on copper demand is debated. Some people invest in copper through copper mining stocks, ETFs, and futures. Others store physical copper in the form of copper bars or rounds although these tend to carry a higher premium in comparison to precious metals. Those who want to avoid the premiums of copper bullion alternatively store old copper wire, copper tubing or American pennies made before 1982.
Copper is commonly used in jewelry, and according to some folklore, copper bracelets relieve arthritis symptoms. In one trial for osteoarthritis and one trial for rheumatoid arthritis no differences is found between copper bracelet and control (non-copper) bracelet. No evidence shows that copper can be absorbed through the skin. If it were, it might lead to copper poisoning.
Recently, some compression clothing with inter-woven copper has been marketed with health claims similar to the folk medicine claims. Because compression clothing is a valid treatment for some ailments, the clothing may have that benefit, but the added copper may have no benefit beyond a placebo effect.
Chromobacterium violaceum and Pseudomonas fluorescens can both mobilize solid copper as a cyanide compound. The ericoid mycorrhizal fungi associated with Calluna, Erica and Vaccinium can grow in metalliferous soils containing copper. The ectomycorrhizal fungus Suillus luteus protects young pine trees from copper toxicity. A sample of the fungus Aspergillus niger was found growing from gold mining solution and was found to contain cyano complexes of such metals as gold, silver, copper, iron, and zinc. The fungus also plays a role in the solubilization of heavy metal sulfides.
Copper proteins have diverse roles in biological electron transport and oxygen transportation, processes that exploit the easy interconversion of Cu(I) and Cu(II). Copper is essential in the aerobic respiration of all eukaryotes. In mitochondria, it is found in cytochrome c oxidase, which is the last protein in oxidative phosphorylation. Cytochrome c oxidase is the protein that binds the O2 between a copper and an iron; the protein transfers 8 electrons to the O2 molecule to reduce it to two molecules of water. Copper is also found in many superoxide dismutases, proteins that catalyze the decomposition of superoxides by converting it (by disproportionation) to oxygen and hydrogen peroxide:
- Cu2+-SOD + O2− → Cu+-SOD + O2 (reduction of copper; oxidation of superoxide)
- Cu+-SOD + O2− + 2H+ → Cu2+-SOD + H2O2 (oxidation of copper; reduction of superoxide)
The protein hemocyanin is the oxygen carrier in most mollusks and some arthropods such as the horseshoe crab (Limulus polyphemus). Because hemocyanin is blue, these organisms have blue blood rather than the red blood of iron-based hemoglobin. Structurally related to hemocyanin are the laccases and tyrosinases. Instead of reversibly binding oxygen, these proteins hydroxylate substrates, illustrated by their role in the formation of lacquers. The biological role for copper commenced with the appearance of oxygen in earth's atmosphere. Several copper proteins, such as the "blue copper proteins", do not interact directly with substrates; hence they are not enzymes. These proteins relay electrons by the process called electron transfer.
Chemical compounds which were developed for treatment of Wilson's disease have been investigated for use in cancer therapy.
Copper is an essential trace element in plants and animals, but not all microorganisms. The human body contains copper at a level of about 1.4 to 2.1 mg per kg of body mass. Copper is absorbed in the gut, then transported to the liver bound to albumin. After processing in the liver, copper is distributed to other tissues in a second phase, which involves the protein ceruloplasmin, carrying the majority of copper in blood. Ceruloplasmin also carries the copper that is excreted in milk, and is particularly well-absorbed as a copper source. Copper in the body normally undergoes enterohepatic circulation (about 5 mg a day, vs. about 1 mg per day absorbed in the diet and excreted from the body), and the body is able to excrete some excess copper, if needed, via bile, which carries some copper out of the liver that is not then reabsorbed by the intestine.
The U.S. Institute of Medicine (IOM) updated the estimated average requirements (EARs) and recommended dietary allowances (RDAs) for copper in 2001. If there is not sufficient information to establish EARs and RDAs, an estimate designated Adequate Intake (AI) is used instead. The AIs for copper are: 200 μg of copper for 0–6-month-old males and females, and 220 μg of copper for 7–12-month-old males and females. The RDAs for copper are: 340 μg of copper for 1–3-year-old males, 440 μg of copper for 4–8-year-old males, 700 μg of copper for 9–13-year-old males, 890 μg of copper for 14–18-year-old males, and 900 μg of copper for males that are 19 years old and older. The RDAs for copper are: 340 μg of copper for 1–3-year-old females, 440 μg of copper for 4–8-year-old females, 700 μg of copper for 9–13-year-old females, 890 μg of copper for 14–18-year-old females, and 900 μg of copper for females that are 19 years old and older. The RDAs for copper are: 1,000 μg of copper for 14–50-year-old pregnant females; furthermore, 1,300 μg of copper for 14–50-year-old lactating females. As for safety, the IOM also sets Tolerable upper intake levels (ULs) for vitamins and minerals when evidence is sufficient. In the case of copper the UL is set at 10 mg/day. Collectively the EARs, RDAs, AIs and ULs are referred to as Dietary Reference Intakes.
The European Food Safety Authority (EFSA) refers to the collective set of information as Dietary Reference Values, with Population Reference Intake (PRI) instead of RDA, and Average Requirement instead of EAR. AI and UL defined the same as in United States. For women and men ages 18 and older the AIs are set at 1.3 and 1.6 mg/day, respectively. AIs for pregnancy and lactation is 1.5 mg/day. For children ages 1–17 years the AIs increase with age from 0.7 to 1.3 mg/day. These AIs are higher than the U.S. RDAs. The European Food Safety Authority reviewed the same safety question and set its UL at 5 mg/day, which is half the U.S. value.
For U.S. food and dietary supplement labeling purposes the amount in a serving is expressed as a percent of Daily Value (%DV). For copper labeling purposes 100% of the Daily Value was 2.0 mg, but as of May 27, 2016[update] it was revised to 0.9 mg to bring it into agreement with the RDA. A table of the old and new adult Daily Values is provided at Reference Daily Intake. The original deadline to be in compliance was July 28, 2018, but on September 29, 2017 the FDA released a proposed rule that extended the deadline to January 1, 2020 for large companies and January 1, 2021 for small companies.
Because of its role in facilitating iron uptake, copper deficiency can produce anemia-like symptoms, neutropenia, bone abnormalities, hypopigmentation, impaired growth, increased incidence of infections, osteoporosis, hyperthyroidism, and abnormalities in glucose and cholesterol metabolism. Conversely, Wilson's disease causes an accumulation of copper in body tissues.
Severe deficiency can be found by testing for low plasma or serum copper levels, low ceruloplasmin, and low red blood cell superoxide dismutase levels; these are not sensitive to marginal copper status. The "cytochrome c oxidase activity of leucocytes and platelets" has been stated as another factor in deficiency, but the results have not been confirmed by replication.
Gram quantities of various copper salts have been taken in suicide attempts and produced acute copper toxicity in humans, possibly due to redox cycling and the generation of reactive oxygen species that damage DNA. Corresponding amounts of copper salts (30 mg/kg) are toxic in animals. A minimum dietary value for healthy growth in rabbits has been reported to be at least 3 ppm in the diet. However, higher concentrations of copper (100 ppm, 200 ppm, or 500 ppm) in the diet of rabbits may favorably influence feed conversion efficiency, growth rates, and carcass dressing percentages.
Chronic copper toxicity does not normally occur in humans because of transport systems that regulate absorption and excretion. Autosomal recessive mutations in copper transport proteins can disable these systems, leading to Wilson's disease with copper accumulation and cirrhosis of the liver in persons who have inherited two defective genes.
In the US, the Occupational Safety and Health Administration (OSHA) has designated a permissible exposure limit (PEL) for copper dust and fumes in the workplace as a time-weighted average (TWA) of 1 mg/m3. The National Institute for Occupational Safety and Health (NIOSH) has set a Recommended exposure limit (REL) of 1 mg/m3, time-weighted average. The IDLH (immediately dangerous to life and health) value is 100 mg/m3.
Copper is a constituent of tobacco smoke. The tobacco plant readily absorbs and accumulates heavy metals, such as copper from the surrounding soil into its leaves. These are readily absorbed into the user's body following smoke inhalation. The health implications are not clear.
- Meija, Juris; et al. (2016). "Atomic weights of the elements 2013 (IUPAC Technical Report)". Pure and Applied Chemistry. 88 (3): 265–91. doi:10.1515/pac-2015-0305.
- Lide, D. R., ed. (2005). "Magnetic susceptibility of the elements and inorganic compounds". CRC Handbook of Chemistry and Physics (PDF) (86th ed.). Boca Raton (FL): CRC Press. ISBN 0-8493-0486-5.
- Weast, Robert (1984). CRC, Handbook of Chemistry and Physics. Boca Raton, Florida: Chemical Rubber Company Publishing. pp. E110. ISBN 0-8493-0464-4.
- McHenry, Charles, ed. (1992). The New Encyclopedia Britannica. 3 (15 ed.). Chicago: Encyclopedia Britannica, Inc. p. 612. ISBN 978-0-85229-553-3.
- "Copper". Merriam-Webster Dictionary. 2018. Retrieved 22 August 2018.
- Johnson, MD PhD, Larry E., ed. (2008). "Copper". Merck Manual Home Health Handbook. Merck Sharp & Dohme Corp., a subsidiary of Merck & Co., Inc. Retrieved 7 April 2013.
- "Copper in human health".
- George L. Trigg; Edmund H. Immergut (1992). Encyclopedia of applied physics. 4: Combustion to Diamagnetism. VCH Publishers. pp. 267–272. ISBN 978-3-527-28126-8. Retrieved 2 May 2011.
- Smith, William F. & Hashemi, Javad (2003). Foundations of Materials Science and Engineering. McGraw-Hill Professional. p. 223. ISBN 978-0-07-292194-6.
- Hammond, C.R. (2004). The Elements, in Handbook of Chemistry and Physics (81st ed.). CRC press. ISBN 978-0-8493-0485-9.
- Resistance Welding Manufacturing Alliance (2003). Resistance Welding Manual (4th ed.). Resistance Welding Manufacturing Alliance. pp. 18–12. ISBN 978-0-9624382-0-2.
- Chambers, William; Chambers, Robert (1884). Chambers's Information for the People. L (5th ed.). W. & R. Chambers. p. 312. ISBN 978-0-665-46912-1.
- "Galvanic Corrosion". Corrosion Doctors. Retrieved 29 April 2011.
- Grieken, Rene van; Janssens, Koen (2005). Cultural Heritage Conservation and Environmental Impact Assessment by Non-Destructive Testing and Micro-Analysis. CRC Press. p. 197. ISBN 978-0-203-97078-2.
- "Copper.org: Education: Statue of Liberty: Reclothing the First Lady of Metals – Repair Concerns". Copper.org. Retrieved 11 April 2011.
- Rickett, B.I.; Payer, J.H. (1995). "Composition of Copper Tarnish Products Formed in Moist Air with Trace Levels of Pollutant Gas: Hydrogen Sulfide and Sulfur Dioxide/Hydrogen Sulfide". Journal of the Electrochemical Society. 142 (11): 3723–3728. doi:10.1149/1.2048404.
- Audi, Georges; Bersillon, Olivier; Blachot, Jean; Wapstra, Aaldert Hendrik (2003), "The NUBASE evaluation of nuclear and decay properties", Nuclear Physics A, 729: 3–128, Bibcode:2003NuPhA.729....3A, doi:10.1016/j.nuclphysa.2003.11.001
- "Interactive Chart of Nuclides". National Nuclear Data Center. Retrieved 8 April 2011.
- Okazawad, Hidehiko; Yonekura, Yoshiharu; Fujibayashi, Yasuhisa; Nishizawa, Sadahiko; Magata, Yasuhiro; Ishizu, Koichi; Tanaka, Fumiko; Tsuchida, Tatsuro; Tamaki, Nagara; Konishi, Junji (1994). "Clinical Application and Quantitative Evaluation of Generator-Produced Copper-62-PTSM as a Brain Perfusion Tracer for PET" (PDF). Journal of Nuclear Medicine. 35 (12): 1910–1915. PMID 7989968.
- Romano, Donatella; Matteucci, Fransesca (2007). "Contrasting copper evolution in ω Centauri and the Milky Way". Monthly Notices of the Royal Astronomical Society: Letters. 378 (1): L59–L63. arXiv:astro-ph/0703760. Bibcode:2007MNRAS.378L..59R. doi:10.1111/j.1745-3933.2007.00320.x.
- Emsley, John (2003). Nature's building blocks: an A–Z guide to the elements. Oxford University Press. pp. 121–125. ISBN 978-0-19-850340-8. Retrieved 2 May 2011.
- Rickwood, P.C. (1981). "The largest crystals" (PDF). American Mineralogist. 66: 885.
- Randazzo, Ryan (19 June 2011). "A new method to harvest copper". Azcentral.com. Retrieved 25 April 2014.
- Gordon, R.B.; Bertram, M.; Graedel, T.E. (2006). "Metal stocks and sustainability". Proceedings of the National Academy of Sciences. 103 (5): 1209–1214. Bibcode:2006PNAS..103.1209G. doi:10.1073/pnas.0509498103. PMC 1360560. PMID 16432205.
- Leonard, Andrew (2 March 2006). "Peak copper?". Salon – How the World Works. Archived from the original on 7 March 2008. Retrieved 23 March 2008.
- Brown, Lester (2006). Plan B 2.0: Rescuing a Planet Under Stress and a Civilization in Trouble. New York: W.W. Norton. p. 109. ISBN 978-0-393-32831-8.
- Schmitz, Christopher (1986). "The Rise of Big Business in the World, Copper Industry 1870–1930". Economic History Review. 2. 39 (3): 392–410. doi:10.1111/j.1468-0289.1986.tb00411.x. JSTOR 2596347.
- "Copper Trends: Live Metal Spot Prices". Archived from the original on 1 May 2012.
- Ackerman, R. (2 April 2009). "A Bottom In Sight For Copper". Forbes.
- Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. ISBN 978-0-08-037941-8.
- Watling, H.R. (2006). "The bioleaching of sulphide minerals with emphasis on copper sulphides — A review" (PDF). Hydrometallurgy. 84 (1): 81–108. doi:10.1016/j.hydromet.2006.05.001. Archived from the original (PDF) on 18 August 2011.
- Samans, Carl (1949). Engineering metals and their alloys. New York: Macmillan. OCLC 716492542.
- Burton, Julie McCulloch (2015). Pen to Paper: Making Fun of Life. iUniverse. ISBN 978-1-4917-5394-1.
- Bahadir, Ali Mufit; Duca, Gheorghe (2009). The Role of Ecological Chemistry in Pollution Research and Sustainable Development. Springer. ISBN 978-90-481-2903-4.
- Green, Dan (2016). The Periodic Table in Minutes. Quercus. ISBN 978-1-68144-329-4.
- "International Copper Association".
- "Overview of Recycled Copper" Copper.org. (25 August 2010). Retrieved on 8 November 2011.
- "Dime". US Mint. Retrieved 9 July 2019.
- "Pride and skill – the 10-cent coin". Royal Canadian Mint. Retrieved 9 July 2019.
- "Gold Jewellery Alloys". World Gold Council. Archived from the original on 14 April 2009. Retrieved 6 June 2009.
- Balver Zinn Solder Sn97Cu3 Archived 7 July 2011 at the Wayback Machine. (PDF) . balverzinn.com. Retrieved on 8 November 2011.
- Deane, D. V. "Modern Coinage Systems" (PDF). British Numismatic Society. Retrieved 1 July 2019.
- "What is 90% Silver?". American Precious Metals Exchange (APMEX). Retrieved 1 July 2019.
- Corrosion Tests and Standards. ASTM International. 2005. p. 368.
- Oguchi, Hachiro (1983). "Japanese Shakudō: its history, properties and production from gold-containing alloys". Gold Bulletin. 16 (4): 125–132. doi:10.1007/BF03214636.
- Holleman, A.F.; Wiberg, N. (2001). Inorganic Chemistry. San Diego: Academic Press. ISBN 978-0-12-352651-9.
- Trammell, Rachel; Rajabimoghadam, Khashayar; Garcia-Bosch, Isaac (30 January 2019). "Copper-Promoted Functionalization of Organic Molecules: from Biologically Relevant Cu/O2 Model Systems to Organometallic Transformations". Chemical Reviews. 119 (4): 2954–3031. doi:10.1021/acs.chemrev.8b00368. PMC 6571019. PMID 30698952.
- Wiley-Vch (2 April 2007). "Nonsystematic (Contact) Fungicides". Ullmann's Agrochemicals. p. 623. ISBN 978-3-527-31604-5.
- Ralph L. Shriner, Christine K.F. Hermann, Terence C. Morrill, David Y. Curtin, Reynold C. Fuson "The Systematic Identification of Organic Compounds" 8th edition, J. Wiley, Hoboken. ISBN 0-471-21503-1
- Saalwächter, Kay; Burchard, Walther; Klüfers, Peter; Kettenbach, G.; Mayer, Peter; Klemm, Dieter; Dugarmaa, Saran (2000). "Cellulose Solutions in Water Containing Metal Complexes". Macromolecules. 33 (11): 4094–4107. Bibcode:2000MaMol..33.4094S. doi:10.1021/ma991893m.
- "Modern Organocopper Chemistry" Norbert Krause, Ed., Wiley-VCH, Weinheim, 2002. ISBN 978-3-527-29773-3.
- Berná, José; Goldup, Stephen; Lee, Ai-Lan; Leigh, David; Symes, Mark; Teobaldi, Gilberto; Zerbetto, Fransesco (26 May 2008). "Cadiot–Chodkiewicz Active Template Synthesis of Rotaxanes and Switchable Molecular Shuttles with Weak Intercomponent Interactions". Angewandte Chemie. 120 (23): 4464–4468. doi:10.1002/ange.200800891.
- Rafael Chinchilla & Carmen Nájera (2007). "The Sonogashira Reaction: A Booming Methodology in Synthetic Organic Chemistry". Chemical Reviews. 107 (3): 874–922. doi:10.1021/cr050992x. PMID 17305399.
- "An Addition of an Ethylcopper Complex to 1-Octyne: (E)-5-Ethyl-1,4-Undecadiene" (PDF). Organic Syntheses. 64: 1. 1986. doi:10.15227/orgsyn.064.0001. Archived from the original (PDF) on 19 June 2012.
- Kharasch, M.S.; Tawney, P.O. (1941). "Factors Determining the Course and Mechanisms of Grignard Reactions. II. The Effect of Metallic Compounds on the Reaction between Isophorone and Methylmagnesium Bromide". Journal of the American Chemical Society. 63 (9): 2308–2316. doi:10.1021/ja01854a005.
- Imai, Sadako; Fujisawa, Kiyoshi; Kobayashi, Takako; Shirasawa, Nobuhiko; Fujii, Hiroshi; Yoshimura, Tetsuhiko; Kitajima, Nobumasa; Moro-oka, Yoshihiko (1998). "63Cu NMR Study of Copper(I) Carbonyl Complexes with Various Hydrotris(pyrazolyl)borates: Correlation between 63Cu Chemical Shifts and CO Stretching Vibrations". Inorganic Chemistry. 37 (12): 3066–3070. doi:10.1021/ic970138r.
- G. Brauer, ed. (1963). "Potassium Cuprate (III)". Handbook of Preparative Inorganic Chemistry. 1 (2nd ed.). NY: Academic Press. p. 1015.
- Schwesinger, Reinhard; Link, Reinhard; Wenzl, Peter; Kossek, Sebastian (2006). "Anhydrous phosphazenium fluorides as sources for extremely reactive fluoride ions in solution". Chemistry: A European Journal. 12 (2): 438–45. doi:10.1002/chem.200500838. PMID 16196062.
- Lewis, E.A.; Tolman, W.B. (2004). "Reactivity of Dioxygen-Copper Systems". Chemical Reviews. 104 (2): 1047–1076. doi:10.1021/cr020633r. PMID 14871149.
- McDonald, M.R.; Fredericks, F.C.; Margerum, D.W. (1997). "Characterization of Copper(III)–Tetrapeptide Complexes with Histidine as the Third Residue". Inorganic Chemistry. 36 (14): 3119–3124. doi:10.1021/ic9608713. PMID 11669966.
- Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. p. 1187. ISBN 978-0-08-037941-8.
- A Timeline of Copper Technologies, Copper Development Association, https://www.copper.org/education/history/timeline/
- "CSA – Discovery Guides, A Brief History of Copper". Csa.com. Retrieved 12 September 2008.
- Rayner W. Hesse (2007). Jewelrymaking through History: an Encyclopedia. Greenwood Publishing Group. p. 56. ISBN 978-0-313-33507-5.No primary source is given in that book.
- "Copper". Elements.vanderkrogt.net. Retrieved 12 September 2008.
- Renfrew, Colin (1990). Before civilization: the radiocarbon revolution and prehistoric Europe. Penguin. ISBN 978-0-14-013642-5. Retrieved 21 December 2011.
- Cowen, R. "Essays on Geology, History, and People: Chapter 3: Fire and Metals". Retrieved 7 July 2009.
- Timberlake, S. & Prag A.J.N.W. (2005). The Archaeology of Alderley Edge: Survey, excavation and experiment in an ancient mining landscape. Oxford: John and Erica Hedges Ltd. p. 396.
- "CSA – Discovery Guides, A Brief History of Copper". CSA Discovery Guides. Retrieved 29 April 2011.
- Pleger, Thomas C. "A Brief Introduction to the Old Copper Complex of the Western Great Lakes: 4000–1000 BC", Proceedings of the Twenty-seventh Annual Meeting of the Forest History Association of Wisconsin, Oconto, Wisconsin, 5 October 2002, pp. 10–18.
- Emerson, Thomas E. and McElrath, Dale L. Archaic Societies: Diversity and Complexity Across the Midcontinent, SUNY Press, 2009 ISBN 1-4384-2701-8.
- Dainian, Fan. Chinese Studies in the History and Philosophy of Science and Technology. p. 228.
- Wallach, Joel. Epigenetics: The Death of the Genetic Theory of Disease Transmission.
- Radivojević, Miljana; Rehren, Thilo (December 2013). "Tainted ores and the rise of tin bronzes in Eurasia, c. 6500 years ago". Antiquity Publications Ltd.
- McNeil, Ian (2002). Encyclopaedia of the History of Technology. London; New York: Routledge. pp. 13, 48–66. ISBN 978-0-203-19211-5.
- Rickard, T.A. (1932). "The Nomenclature of Copper and its Alloys". Journal of the Royal Anthropological Institute. 62: 281–290. doi:10.2307/2843960. JSTOR 2843960.
- Martin, Susan R. (1995). "The State of Our Knowledge About Ancient Copper Mining in Michigan". The Michigan Archaeologist. 41 (2–3): 119. Archived from the original on 7 February 2016.
- Hong, S.; Candelone, J.-P.; Patterson, C.C.; Boutron, C.F. (1996). "History of Ancient Copper Smelting Pollution During Roman and Medieval Times Recorded in Greenland Ice". Science. 272 (5259): 246–249 (247f.). Bibcode:1996Sci...272..246H. doi:10.1126/science.272.5259.246.
- de Callataÿ, François (2005). "The Graeco-Roman Economy in the Super Long-Run: Lead, Copper, and Shipwrecks". Journal of Roman Archaeology. 18: 361–372 (366–369). doi:10.1017/S104775940000742X.
- Savenije, Tom J.; Warman, John M.; Barentsen, Helma M.; van Dijk, Marinus; Zuilhof, Han; Sudhölter, Ernst J.R. (2000). "Corinthian Bronze and the Gold of the Alchemists" (PDF). Macromolecules. 33 (2): 60–66. Bibcode:2000MaMol..33...60S. doi:10.1021/ma9904870. Archived from the original (PDF) on 29 September 2007.
- Lynch, Martin (2004). Mining in World History. p. 60. ISBN 978-1-86189-173-0.
- "Gold: prices, facts, figures and research: A brief history of money". Retrieved 22 April 2011.
- "Copper and Brass in Ships". Retrieved 6 September 2016.
- Stelter, M.; Bombach, H. (2004). "Process Optimization in Copper Electrorefining". Advanced Engineering Materials. 6 (7): 558–562. doi:10.1002/adem.200400403.
- Gardner, E. D.; et al. (1938). Copper Mining in North America. Washington, D. C.: U. S. Bureau of Mines. Retrieved 19 March 2019.
- Hyde, Charles (1998). Copper for America, the United States Copper Industry from Colonial Times to the 1990s. Tucson, Arizona: University of Arizona Press. p. passim. ISBN 0-8165-1817-3.
- "Outokumpu Flash Smelting" (PDF). Outokumpu. p. 2. Archived from the original (PDF) on 24 July 2011.
- Karen A. Mingst (1976). "Cooperation or illusion: an examination of the intergovernmental council of copper exporting countries". International Organization. 30 (2): 263–287. doi:10.1017/S0020818300018270.
- Ryck Lydecker. "Is Copper Bottom Paint Sinking?". BoatUS Magazine. Retrieved 3 June 2016.
- "Copper". American Elements. 2008. Retrieved 12 July 2008.
- Pops, Horace, 2008, "Processing of wire from antiquity to the future", Wire Journal International, June, pp. 58–66
- The Metallurgy of Copper Wire, http://www.litz-wire.com/pdf%20files/Metallurgy_Copper_Wire.pdf
- Joseph, Günter, 1999, Copper: Its Trade, Manufacture, Use, and Environmental Status, edited by Kundig, Konrad J.A., ASM International, pp. 141–192 and pp. 331–375.
- "Copper, Chemical Element – Overview, Discovery and naming, Physical properties, Chemical properties, Occurrence in nature, Isotopes". Chemistryexplained.com. Retrieved 16 October 2012.
- Joseph, Günter, 1999, Copper: Its Trade, Manufacture, Use, and Environmental Status, edited by Kundig, Konrad J.A., ASM International, p.348
- "Aluminum Wiring Hazards and Pre-Purchase Inspections". www.heimer.com. Retrieved 3 June 2016.
- "Accelerator: Waveguides (SLAC VVC)". SLAC Virtual Visitor Center. Retrieved 29 April 2011.
- IE3 energy-saving motors, Engineer Live, http://www.engineerlive.com/Design-Engineer/Motors_and_Drives/IE3_energy-saving_motors/22687/
- Energy‐efficiency policy opportunities for electric motor‐driven systems, International Energy Agency, 2011 Working Paper in the Energy Efficiency Series, by Paul Waide and Conrad U. Brunner, OECD/IEA 2011
- Fuchsloch, J. and E.F. Brush, (2007), "Systematic Design Approach for a New Series of Ultra‐NEMA Premium Copper Rotor Motors", in EEMODS 2007 Conference Proceedings, 10–15 June, Beijing.
- Copper motor rotor project; Copper Development Association; "Archived copy". Archived from the original on 13 March 2012. Retrieved 7 November 2012.CS1 maint: Archived copy as title (link)
- NEMA Premium Motors, The Association of Electrical Equipment and Medical Imaging Manufacturers; "Archived copy". Archived from the original on 2 April 2010. Retrieved 2009-10-12.CS1 maint: Archived copy as title (link)
- Seale, Wayne (2007). The role of copper, brass, and bronze in architecture and design; Metal Architecture, May 2007
- Copper roofing in detail; Copper in Architecture; Copper Development Association, U.K., www.cda.org.uk/arch
- Architecture, European Copper Institute; http://eurocopper.org/copper/copper-architecture.html Archived 9 October 2012 at the Wayback Machine
- Kronborg completed; Agency for Palaces and Cultural Properties, København, "Archived copy". Archived from the original on 24 October 2012. Retrieved 2012-09-12.CS1 maint: Archived copy as title (link)
- Berg, Jan. "Why did we paint the library's roof?". Archived from the original on 25 June 2007. Retrieved 20 September 2007.
- Architectural considerations; Copper in Architecture Design Handbook, http://www.copper.org/applications/architecture/arch_dhb/fundamentals/arch_considerations.htm
- Peters, Larry E. (2004). Preventing corrosion on copper roofing systems; Professional Roofing, October 2004, http://www.professionalroofing.net
- Oxidation Reaction: Why is the Statue of Liberty Blue-Green? Engage Students in Engineering; www.EngageEngineering.org; Chun Wu, Ph.D., Mount Marty College; Funded by the National Science Foundation (NSF) under Grant No. 083306. "Archived copy" (PDF). Archived from the original (PDF) on 25 October 2013. Retrieved 2013-10-25.CS1 maint: Archived copy as title (link)
- Fitzgerald, K.P.; Nairn, J.; Atrens, A. (1998). "The chemistry of copper patination". Corrosion Science. 40 (12): 2029–50. doi:10.1016/S0010-938X(98)00093-6.
- Application Areas: Architecture – Finishes – patina; http://www.copper.org/applications/architecture/finishes.html
- Glossary of copper terms, Copper Development Association (UK): "Archived copy". Archived from the original on 20 August 2012. Retrieved 14 September 2012.CS1 maint: Archived copy as title (link)
- Finishes – natural weathering; Copper in Architecture Design Handbook, Copper Development Association Inc., "Archived copy". Archived from the original on 16 October 2012. Retrieved 12 September 2012.CS1 maint: Archived copy as title (link)
- Davis, Joseph R. (2001). Copper and Copper Alloys. ASM International. pp. 3–6, 266. ISBN 978-0-87170-726-0.
- Edding, Mario E., Flores, Hector, and Miranda, Claudio, (1995), Experimental Usage of Copper-Nickel Alloy Mesh in Mariculture. Part 1: Feasibility of usage in a temperate zone; Part 2: Demonstration of usage in a cold zone; Final report to the International Copper Association Ltd.
- Corrosion Behaviour of Copper Alloys used in Marine Aquaculture. (PDF) . copper.org. Retrieved on 8 November 2011.
- Copper Touch Surfaces Archived 23 July 2012 at the Wayback Machine. Copper Touch Surfaces. Retrieved on 8 November 2011.
- EPA registers copper-containing alloy products, May 2008
- Biurrun, Amaya; Caballero, Luis; Pelaz, Carmen; León, Elena; Gago, Alberto (1999). "Treatment of a Legionella pneumophila‐Colonized Water Distribution System Using Copper‐Silver Ionization and Continuous Chlorination". Infection Control and Hospital Epidemiology. 20 (6): 426–428. doi:10.1086/501645. JSTOR 30141645. PMID 10395146.
- Chilean subway protected with Antimicrobial Copper – Rail News from Archived 24 July 2012 at the Wayback Machine. rail.co. Retrieved on 8 November 2011.
- Codelco to provide antimicrobial copper for new metro lines (Chile)[dead link]. Construpages.com.ve. Retrieved on 8 November 2011.
- PR 811 Chilean Subway Installs Antimicrobial Copper Archived 23 November 2011 at the Wayback Machine. (PDF). antimicrobialcopper.com. Retrieved on 8 November 2011.
- "Copper and Cupron". Cupron.[unreliable source?]
- Ergowear, Copper antimicrobial yarn technology used in male underwear[unreliable source?]
- "Global copper market under supplied, demand on the rise — report". Mining.com. 6 January 2019. Retrieved 13 January 2019.
- "Will the Transition to Renewable Energy Be Paved in Copper?". www.renewableenergyworld.com. 15 January 2015. Retrieved 13 January 2019.
- "Copper and cars: Boom goes beyond electric vehicles". MINING.com. 18 June 2018. Retrieved 13 January 2019.
- "Impact of electric cars in medium-term copper demand 'overrated', experts say". MINING.com. 12 April 2018. Retrieved 13 January 2019.
- "Why are Premiums for Copper Bullion So High?". Provident Metals. 20 August 2012. Retrieved 23 January 2019.
- Chace, Zoe. "Penny Hoarders Hope For The Day The Penny Dies". NPR. NPR. Retrieved 23 January 2019.
- Walker, W.R.; Keats, D.M. (1976). "An investigation of the therapeutic value of the 'copper bracelet'-dermal assimilation of copper in arthritic/rheumatoid conditions". Agents and Actions. 6 (4): 454–459. PMID 961545.
- Richmond SJ, Gunadasa S, Bland M, Macpherson H (2013). "Copper bracelets and magnetic wrist straps for rheumatoid arthritis – analgesic and anti-inflammatory effects: a randomised double-blind placebo controlled crossover trial". PLoS ONE. 8 (9): e71529. Bibcode:2013PLoSO...871529R. doi:10.1371/journal.pone.0071529. PMC 3774818. PMID 24066023.
- Richmond, Stewart J.; Brown, Sally R.; Campion, Peter D.; Porter, Amanda J.L.; Moffett, Jennifer A. Klaber; Jackson, David A.; Featherstone, Valerie A.; Taylor, Andrew J. (2009). "Therapeutic effects of magnetic and copper bracelets in osteoarthritis: A randomised placebo-controlled crossover trial". Complementary Therapies in Medicine. 17 (5–6): 249–256. doi:10.1016/j.ctim.2009.07.002. ISSN 0965-2299. PMID 19942103.
- University of Arkansas for Medical Sciences:
Find the Truth Behind Medical Myths Archived 6 January 2014 at the Wayback Machine
While it's never been proven that copper can be absorbed through the skin by wearing a bracelet, research has shown that excessive copper can result in poisoning, causing vomiting and, in severe cases, liver damage.
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- Geoffrey Michael Gadd (March 2010). "Metals, minerals and microbes: geomicrobiology and bioremediation". Microbiology. 156 (3): 609–643. doi:10.1099/mic.0.037143-0. PMID 20019082.
- Harbhajan Singh (2006). Mycoremediation: Fungal Bioremediation. p. 509. ISBN 978-0-470-05058-3.
- Vest, Katherine E.; Hashemi, Hayaa F.; Cobine, Paul A. (2013). "Chapter 13 The Copper Metallome in Eukaryotic Cells". In Banci, Lucia (ed.). Metallomics and the Cell. Metal Ions in Life Sciences. 12. Springer. doi:10.1007/978-94-007-5561-10_12 (inactive 20 August 2019). ISBN 978-94-007-5560-4. electronic-book ISBN 978-94-007-5561-1 ISSN 1559-0836 electronic-ISSN 1868-0402
- "Fun facts". Horseshoe crab. University of Delaware. Retrieved 13 July 2008.
- S.J. Lippard, J.M. Berg "Principles of bioinorganic chemistry" University Science Books: Mill Valley, CA; 1994. ISBN 0-935702-73-3.
- Decker, H. & Terwilliger, N. (2000). "COPs and Robbers: Putative evolution of copper oxygen-binding proteins". Journal of Experimental Biology. 203 (Pt 12): 1777–1782. PMID 10821735.
- Schneider, Lisa K.; Wüst, Anja; Pomowski, Anja; Zhang, Lin; Einsle, Oliver (2014). "Chapter 8. No Laughing Matter: The Unmaking of the Greenhouse Gas Dinitrogen Monoxide by Nitrous Oxide Reductase". In Peter M.H. Kroneck; Martha E. Sosa Torres (eds.). The Metal-Driven Biogeochemistry of Gaseous Compounds in the Environment. Metal Ions in Life Sciences. 14. Springer. pp. 177–210. doi:10.1007/978-94-017-9269-1_8. ISBN 978-94-017-9268-4. PMID 25416395.
- Denoyer, Delphine; Clatworthy, Sharnel A.S.; Cater, Michael A. (2018). "Chapter 16. Copper Complexes in Cancer Therapy". In Sigel, Astrid; Sigel, Helmut; Freisinger, Eva; Sigel, Roland K.O. (eds.). Metallo-Drugs: Development and Action of Anticancer Agents. Metal Ions in Life Sciences. 18. Berlin: de Gruyter GmbH. pp. 469–506. doi:10.1515/9783110470734-022. ISBN 978-3-11-047073-4. PMID 29394035.
- "Amount of copper in the normal human body, and other nutritional copper facts". Retrieved 3 April 2009.
- Adelstein, S. J.; Vallee, B. L. (1961). "Copper metabolism in man". New England Journal of Medicine. 265 (18): 892–897. doi:10.1056/NEJM196111022651806. PMID 13859394.
- M.C. Linder; Wooten, L.; Cerveza, P.; Cotton, S.; Shulze, R.; Lomeli, N. (1 May 1998). "Copper transport". The American Journal of Clinical Nutrition. 67 (5): 965S–971S. doi:10.1093/ajcn/67.5.965S. PMID 9587137.
- Frieden, E.; Hsieh, H.S. (1976). Ceruloplasmin: The copper transport protein with essential oxidase activity. Advances in Enzymology and Related Areas of Molecular Biology. Advances in Enzymology – and Related Areas of Molecular Biology. 44. pp. 187–236. doi:10.1002/9780470122891.ch6. ISBN 978-0-470-12289-1. JSTOR 20170553. PMID 775938.
- S.S. Percival; Harris, E.D. (1 January 1990). "Copper transport from ceruloplasmin: Characterization of the cellular uptake mechanism". American Journal of Physiology. Cell Physiology. 258 (1): C140–C146. doi:10.1152/ajpcell.1990.258.1.c140. PMID 2301561.
- Dietary Reference Intakes: RDA and AI for Vitamins and Elements Archived 13 November 2018 at the Wayback Machine Food and Nutrition Board, Institute of Medicine, National Academies Press, 2011. Retrieved 18 April 2018.
- Copper. IN: Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Copper. National Academy Press. 2001, PP. 224–257.
- "Overview on Dietary Reference Values for the EU population as derived by the EFSA Panel on Dietetic Products, Nutrition and Allergies" (PDF). 2017.
- Tolerable Upper Intake Levels For Vitamins And Minerals (PDF), European Food Safety Authority, 2006
- "Federal Register May 27, 2016 Food Labeling: Revision of the Nutrition and Supplement Facts Labels. FR p. 33982" (PDF).
- "Changes to the Nutrition Facts Panel – Compliance Date"
- Bonham, Maxine; O'Connor, Jacqueline M.; Hannigan, Bernadette M.; Strain, J.J. (2002). "The immune system as a physiological indicator of marginal copper status?". British Journal of Nutrition. 87 (5): 393–403. doi:10.1079/BJN2002558. PMID 12010579.
- Li, Yunbo; Trush, Michael; Yager, James (1994). "DNA damage caused by reactive oxygen species originating from a copper-dependent oxidation of the 2-hydroxy catechol of estradiol". Carcinogenesis. 15 (7): 1421–1427. doi:10.1093/carcin/15.7.1421. PMID 8033320.
- Gordon, Starkebaum; John, M. Harlan (April 1986). "Endothelial cell injury due to copper-catalyzed hydrogen peroxide generation from homocysteine". J. Clin. Invest. 77 (4): 1370–6. doi:10.1172/JCI112442. PMC 424498. PMID 3514679.
- "Pesticide Information Profile for Copper Sulfate". Cornell University. Retrieved 10 July 2008.
- Hunt, Charles E. & William W. Carlton (1965). "Cardiovascular Lesions Associated with Experimental Copper Deficiency in the Rabbit". Journal of Nutrition. 87 (4): 385–394. doi:10.1093/jn/87.4.385. PMID 5841854.
- Ayyat M.S.; Marai I.F.M.; Alazab A.M. (1995). "Copper-Protein Nutrition of New Zealand White Rabbits under Egyptian Conditions". World Rabbit Science. 3 (3): 113–118. doi:10.4995/wrs.1995.249.
- Brewer GJ. Copper excess, zinc deficiency, and cognition loss in Alzheimer's disease. BioFactors. March 2012;38(2):107–113. doi:10.1002/biof.1005. PMID 22438177.
- "Copper: Alzheimer's Disease". Examine.com. Retrieved 21 June 2015.
- NIOSH Pocket Guide to Chemical Hazards. "#0150". National Institute for Occupational Safety and Health (NIOSH).
- OEHHA Copper
- Talhout, Reinskje; Schulz, Thomas; Florek, Ewa; Van Benthem, Jan; Wester, Piet; Opperhuizen, Antoon (2011). "Hazardous Compounds in Tobacco Smoke". International Journal of Environmental Research and Public Health. 8 (12): 613–628. doi:10.3390/ijerph8020613. ISSN 1660-4601. PMC 3084482. PMID 21556207.
- Pourkhabbaz, A.; Pourkhabbaz, H. (2012). "Investigation of Toxic Metals in the Tobacco of Different Iranian Cigarette Brands and Related Health Issues". Iranian Journal of Basic Medical Sciences. 15 (1): 636–644. PMC 3586865. PMID 23493960.
- Bernhard, David; Rossmann, Andrea; Wick, Georg (2005). "Metals in cigarette smoke". Iubmb Life (International Union of Biochemistry and Molecular Biology: Life). 57 (12): 805–809. doi:10.1080/15216540500459667. PMID 16393783.
|in pure water, or acidic or alkali conditions. Copper in neutral water is more noble than hydrogen.||in water containing sulfide||in 10 M ammonia solution||in a chloride solution|
- Massaro, Edward J., ed. (2002). Handbook of Copper Pharmacology and Toxicology. Humana Press. ISBN 978-0-89603-943-8.
- "Copper: Technology & Competitiveness (Summary) Chapter 6: Copper Production Technology" (PDF). Office of Technology Assessment. 2005.
- Current Medicinal Chemistry, Volume 12, Number 10, May 2005, pp. 1161–1208(48) Metals, Toxicity and Oxidative Stress
- William D. Callister (2003). Materials Science and Engineering: an Introduction (6th ed.). Wiley, New York. Table 6.1, p. 137. ISBN 978-0-471-73696-7.
- Material: Copper (Cu), bulk, MEMS and Nanotechnology Clearinghouse.
- Kim BE; Nevitt T; Thiele DJ (2008). "Mechanisms for copper acquisition, distribution and regulation". Nat. Chem. Biol. 4 (3): 176–85. doi:10.1038/nchembio.72. PMID 18277979.
- Copper transport disorders: an Instant insight from the Royal Society of Chemistry
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- Copper (chemical element) at the Encyclopædia Britannica
- Copper at The Periodic Table of Videos (University of Nottingham)
- Copper and compounds fact sheet from the National Pollutant Inventory of Australia
- CDC–NIOSH Pocket Guide to Chemical Hazards – Copper (dusts and mists) from the Centers for Disease Control and Prevention's National Institute for Occupational Safety and Health
- CDC–NIOSH Pocket Guide to Chemical Hazards – Copper fume from the Centers for Disease Control and Prevention's National Institute for Occupational Safety and Health
- Copper.org – official website of the Copper Development Association with an extensive site of properties and uses of copper
- Price history of copper, according to the IMF