Copper#Biological role

In the Roman era, copper was mined principally on Cyprus, the origin of the name of the metal, from aes cyprium (metal of Cyprus), later corrupted to {{Lang|la|cuprum}} (Latin). {{Lang|ang|Coper}} (Old English) and copper were derived from this, the later spelling first used around 1530.{{cite web|url=https://www.merriam-webster.com/dictionary/copper|publisher=Merriam-Webster Dictionary|title=Copper|date=2018|access-date=22 August 2018}}

File:Cu-Scheibe.JPG; etched to reveal crystallites]]

File:Molten copper in bright sunlight.gif color.]]

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.{{cite book|first1=George L. |last1=Trigg|first2=Edmund H. |last2=Immergut|title=Encyclopedia of Applied Physics|url=https://books.google.com/books?id=sVQ5RAAACAAJ|access-date=2 May 2011|year=1992|publisher=VCH |isbn=978-3-527-28126-8|pages=267–272|volume=4: Combustion to Diamagnetism}} 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.{{cite book|last1 = Smith |first1=William F.|last2 = Hashemi |first2=Javad|name-list-style = amp |title = Foundations of Materials Science and Engineering|page = 223|publisher = McGraw-Hill Professional|date= 2003|isbn = 978-0-07-292194-6}}

The softness of copper partly explains its high electrical conductivity ({{val|59.6|e=6|u=S/m}}) and high thermal conductivity, second highest (second only to silver) among pure metals at room temperature.{{cite book|last = Hammond |first=C. R.|title = The Elements, in Handbook of Chemistry and Physics|edition = 81st|publisher = CRC Press|isbn = 978-0-8493-0485-9|date = 2004|url = https://archive.org/details/crchandbookofche81lide}} 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 possible current density of copper in open air is approximately {{val|3.1|e=6|u=A/m²}}, above which it begins to heat excessively.{{cite book|author=Resistance Welding Manufacturing Alliance |title=Resistance Welding Manual|date=2003|publisher=Resistance Welding Manufacturing Alliance|isbn=978-0-9624382-0-2|edition=4th|pages=18–12}}

Copper is one of a few metallic elements with a natural color other than gray or silver.{{Cite book|last1 = Chambers|first1 = William|last2 = Chambers|first2 = Robert|title = Chambers's Information for the People|publisher = W. & R. Chambers|date = 1884|volume = L|page = 312|edition = 5th|url = https://books.google.com/books?id=eGIMAAAAYAAJ|isbn = 978-0-665-46912-1}} Pure copper is orange-red and acquires a reddish tarnish when exposed to air. This is due to the low plasma frequency of the metal, which lies in the red part of the visible spectrum, causing it to absorb the higher-frequency green and blue colors.{{cite web |last1=Ramachandran |first1=Harishankar |title=Why is Copper Red? |url=http://ee.iitm.ac.in/~hsr/ec301/copper.pdf |website=IIT Madras |access-date=27 December 2022 |date=14 March 2007}}

As with other metals, if copper is put in contact with another metal in the presence of an electrolyte, galvanic corrosion will occur.{{cite web|title=Galvanic Corrosion|url=http://www.corrosion-doctors.org/Forms-galvanic/galvanic-corrosion.htm|work=Corrosion Doctors|access-date=29 April 2011}}

File:Copper wire comparison.JPG

File:Royal Observatory Edinburgh East Tower 2010 cropped.jpg, showing the contrast between the refurbished copper installed in 2010 and the green color of the original 1894 copper]]

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{{Cite book|url=https://books.google.com/books?id=3qL3vfUZHMYC|title=Cultural Heritage Conservation and Environmental Impact Assessment by Non-Destructive Testing and Micro-Analysis|last1=Grieken|first1=Rene van|last2=Janssens|first2=Koen|date=2005|publisher=CRC Press|isbn=978-0-203-97078-2|page=197|language=en}} and the Statue of Liberty.{{cite web|title=Copper.org: Education: Statue of Liberty: Reclothing the First Lady of Metals – Repair Concerns|url=http://www.copper.org/education/liberty/liberty_reclothed1.html|work=Copper.org|access-date=11 April 2011}} Copper tarnishes when exposed to some sulfur compounds, with which it reacts to form various copper sulfides.{{cite journal|last1=Rickett|first1=B. I.|last2=Payer|first2=J. H.|title=Composition of Copper Tarnish Products Formed in Moist Air with Trace Levels of Pollutant Gas: Hydrogen Sulfide and Sulfur Dioxide/Hydrogen Sulfide|journal=Journal of the Electrochemical Society|date=1995|volume=142|issue=11|pages=3723–3728|doi=10.1149/1.2048404|bibcode=1995JElS..142.3723R}}

{{Main|Isotopes of copper}}

There are 29 isotopes of copper. {{SimpleNuclide|Copper|63}} and {{SimpleNuclide|Copper|65}} are stable, with {{SimpleNuclide|Copper|63}} comprising approximately 69% of naturally occurring copper; both have a spin of {{frac|3|2}}.{{NUBASE 2003}} The other isotopes are radioactive, with the most stable being {{SimpleNuclide|Copper|67}} with a half-life of 61.83 hours. Seven metastable isomers have been characterized; {{SimpleNuclide|Copper|68m}} 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⁺. Copper-64, which has a half-life of 12.7 hours, decays both ways.{{cite web |url=http://www.nndc.bnl.gov/chart/reCenter.jsp?z=29&n=35 |title=Interactive Chart of Nuclides |work=National Nuclear Data Center |access-date=8 April 2011 |archive-date=25 August 2013 |archive-url=https://web.archive.org/web/20130825141152/http://www.nndc.bnl.gov/chart/reCenter.jsp?z=29&n=35 |url-status=dead }}

{{SimpleNuclide|Copper|62}} and {{SimpleNuclide|Copper|64}} have significant applications. {{SimpleNuclide|Copper|62}} is used in {{SimpleNuclide|Copper|62}}Cu-PTSM as a radioactive tracer for positron emission tomography.{{Cite journal | last1 = Okazawad | first1 = Hidehiko | last2 = Yonekura | first2 = Yoshiharu | last3 = Fujibayashi | first3 = Yasuhisa | last4 = Nishizawa | first4 = Sadahiko | last5 = Magata | first5 = Yasuhiro | last6 = Ishizu | first6 = Koichi | last7 = Tanaka | first7 = Fumiko | last8 = Tsuchida |first8 = Tatsuro |last9 = Tamaki |first9 = Nagara |last10 = Konishi | first10 = Junji |date=1994 |title=Clinical Application and Quantitative Evaluation of Generator-Produced Copper-62-PTSM as a Brain Perfusion Tracer for PET |journal=Journal of Nuclear Medicine |volume=35 |issue=12 |pages=1910–1915 |url=http://jnm.snmjournals.org/cgi/reprint/35/12/1910.pdf|pmid=7989968 }}

{{See also|List of copper ores}}

File:Native Copper from the Keweenaw Peninsula Michigan.jpg

Copper is produced in massive stars{{cite journal|last1=Romano|first1=Donatella|last2=Matteucci|first2=Fransesca|title=Contrasting copper evolution in ω Centauri and the Milky Way|journal=Monthly Notices of the Royal Astronomical Society: Letters|date=2007|volume=378|issue=1|pages=L59–L63|doi=10.1111/j.1745-3933.2007.00320.x|doi-access=free |bibcode=2007MNRAS.378L..59R|arxiv = astro-ph/0703760|s2cid=14595800}} and is present in the Earth's crust in a proportion of about 50 parts per million (ppm).{{cite book|author=Emsley, John|title=Nature's building blocks: an A–Z guide to the elements|url=https://archive.org/details/naturesbuildingb0000emsl|url-access=registration|access-date=2 May 2011|year=2003|publisher=Oxford University Press|isbn=978-0-19-850340-8|pages=[https://archive.org/details/naturesbuildingb0000emsl/page/121 121]–125}} 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 yet 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 {{nowrap|4.4 × 3.2 × 3.2 cm}}.{{cite journal|url = http://www.minsocam.org/ammin/AM66/AM66_885.pdf|journal = American Mineralogist|volume = 66|page=885|date= 1981|title= The largest crystals|last = Rickwood |first=P. C.}} Copper is the 26th most abundant element in Earth's crust, representing 50 ppm compared with 75 ppm for zinc, and 14 ppm for lead.{{cite book|author=Emsley, John|title=Nature's building blocks: an A–Z guide to the elements|url=https://archive.org/details/naturesbuildingb0000emsl|url-access=registration|access-date=2 May 2011|year=2003|publisher=Oxford University Press|isbn=978-0-19-850340-8|pages=124, 231, 449, 503}}

Typical background concentrations of copper do not exceed {{val|1|u=ng/m3}} in the atmosphere; {{val|150|u=mg/kg}} in soil; {{val|30|u=mg/kg}} in vegetation; 2 μg/L in freshwater and {{val|0.5|u=μg/L}} in seawater.{{Cite book|last=Rieuwerts|first=John|url=https://www.worldcat.org/oclc/886492996|title=The Elements of Environmental Pollution|publisher=Earthscan Routledge|year=2015|isbn=978-0-415-85919-6|location=London and New York|pages=207|oclc=886492996}}

File:Chuquicamata-002.jpg, in Chile, is one of the world's largest open pit copper mines.]]

File:Copper - world production trend.svg

{{see also|List of countries by copper production}}

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. Chile, the world's largest copper producer, supplies the US with 70% of refined copper and alloy imports through 2024. Together with Canada (17%) and Peru (7%), they account for 94% of U.S. copper imports.{{Cite web |last=Schmitz |first=Sophia |date=2025-04-18 |title=Top Copper Suppliers Urge U.S. to Avoid Tariffs, Warn of Global Repercussions |url=https://metals-wire.net/commodities/top-copper-suppliers-urge-u-s-to-avoid-tariffs-warn-of-global-repercussions/ |access-date=2025-04-25 |website=METALS WIRE |language=en}}{{Cite web |last=Solomon |first=Daina Beth |date=April 15, 2025 |title=Chile, Canada and Peru push back against Trump's copper tariff probe |url=https://www.reuters.com/markets/commodities/chile-pushes-back-against-trump-copper-tariff-probe-2025-04-15/ |website=Reuters}} 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.{{cite web |last=Randazzo |first=Ryan |url=https://www.azcentral.com/arizonarepublic/business/articles/2011/06/19/20110619copper-new-method-fight.html |title=A new method to harvest copper |publisher=Azcentral.com |date=19 June 2011 |access-date=25 April 2014 |archive-date=22 June 2011 |archive-url=https://web.archive.org/web/20110622234817/https://www.azcentral.com/arizonarepublic/business/articles/2011/06/19/20110619copper-new-method-fight.html |url-status=dead }} 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.{{cite journal|title=Metal stocks and sustainability|journal=Proceedings of the National Academy of Sciences |date=2006|volume=103|issue=5|pages=1209–1214|first1=R.B.|last1=Gordon|first2=M.|last2=Bertram|first3=T.E.|last3=Graedel|doi=10.1073/pnas.0509498103|pmc=1360560|pmid=16432205|bibcode = 2006PNAS..103.1209G|doi-access=free }} An alternative source of copper for collection currently being researched are polymetallic nodules, which are located at the depths of the Pacific Ocean approximately 3000–6500 meters below sea level. These nodules contain other valuable metals such as cobalt and nickel.{{cite book |last1=Beaudoin |first1=Yannick C. |last2=Baker |first2=Elaine |title=Deep Sea Minerals: Manganese Nodules, a physical, biological, environmental and technical review |date=December 2013 |publisher=Secretariat of the Pacific Community |isbn=978-82-7701-119-6 |pages=7–18 |url=https://www.researchgate.net/publication/264763450 |access-date=8 February 2021 |archive-url=https://web.archive.org/web/20241204095547/https://www.researchgate.net/publication/264763450_The_Geology_of_Manganese_Nodules |archive-date=4 December 2024 |url-status=live }}

Copper has been in use for at least 10,000 years, but more than 95% of all copper ever mined and smelted has been extracted since 1900. 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.{{cite book|author=Brown, Lester|title=Plan B 2.0: Rescuing a Planet Under Stress and a Civilization in Trouble|publisher=New York: W.W. Norton|date=2006|page=[https://archive.org/details/planb20rescuingp00brow_0/page/109 109]|isbn=978-0-393-32831-8|url=https://archive.org/details/planb20rescuingp00brow_0|url-access=registration}} Recycling is a major source of copper in the modern world.{{cite news |last1=Leonard |first1=Andrew |title=Peak copper? |url=https://www.salon.com/2006/03/02/peak_copper/ |access-date=8 March 2022 |work=Salon |date=3 March 2006 |language=en}}

File:Price of Copper.webp

The price of copper is volatile.{{cite journal|last=Schmitz|first=Christopher|title=The Rise of Big Business in the World, Copper Industry 1870–1930|journal=Economic History Review|date=1986|volume=39|series=2|issue=3|pages=392–410|jstor=2596347|doi=10.1111/j.1468-0289.1986.tb00411.x}} After a peak in 2022 the price unexpectedly fell.{{Cite news |title=Copper is unexpectedly getting cheaper |newspaper=The Economist |url=https://www.economist.com/finance-and-economics/2023/07/06/copper-is-unexpectedly-getting-cheaper |access-date=2023-12-19 |issn=0013-0613}} And by May 2024, the price on the London Metal Exchange has reached an all-time high above $11,000 per ton.{{Cite web |date=2024-05-20 |title=Copper price hits record above $11,000 on bets that shortage looms |url=https://www.mining.com/web/copper-price-hits-record-above-11000-on-bets-that-shortage-looms/ |access-date=2025-04-25 |website=MINING.COM |language=en-US}}

The global market for copper is one of the most commodified and financialized of the commodity markets, and has been so for decades.{{Cite book |last=Massot |first=Pascale |title=China's Vulnerability Paradox: How the World's Largest Consumer Transformed Global Commodity Markets |date=2024 |publisher=Oxford University Press |isbn=978-0-19-777140-2 |location=New York, NY, United States of America |pages=}}{{Rp|page=213}}

{{main|Copper extraction}}

File:Copper Flash Smelting Process (EN).svg

The great majority of copper ores are sulfides. Common ores are the sulfides chalcopyrite (CuFeS₂), bornite (Cu₅FeS₄) and, to a lesser extent, covellite (CuS) and chalcocite (Cu₂S).{{Greenwood&Earnshaw2nd|pages=1174–1175}} These ores occur at the level of <1% Cu. Concentration of the ore is required, which begins with comminution followed by froth flotation. The remaining concentrate is smelted, which can be described with two simplified equations:{{cite book |doi=10.1002/14356007.a07_471 |chapter=Copper |title=Ullmann's Encyclopedia of Industrial Chemistry |date=2001 |last1=Lossin |first1=Adalbert |isbn=9783527303854 }}

Cuprous sulfide is oxidized to cuprous oxide:

:2 Cu₂S + 3 O₂ → 2 Cu₂O + 2 SO₂

Cuprous oxide reacts with cuprous sulfide to convert to blister copper upon heating:

:2 Cu₂O + Cu₂S → 6 Cu + 2 SO₂

This roasting gives matte copper, roughly 50% Cu by weight, which is purified by electrolysis. Depending on the ore, sometimes other metals are obtained during the electrolysis including platinum and gold.

Aside from sulfides, another family of ores are oxides. Approximately 15% of the world's copper supply derives from these oxides. The beneficiation process for oxides involves extraction with sulfuric acid solutions followed by electrolysis. In parallel with the above method for "concentrated" sulfide and oxide ores, copper is recovered from mine tailings and heaps. A variety of methods are used including leaching with sulfuric acid, ammonia, ferric chloride. Biological methods are also used.{{cite journal|last=Watling |first=H.R. |title=The bioleaching of sulphide minerals with emphasis on copper sulphides – A review |journal=Hydrometallurgy |date=2006 |volume=84 |issue=1 |pages=81–108 |url=http://infolib.hua.edu.vn/Fulltext/ChuyenDe/ChuyenDe07/CDe53/59.pdf |doi=10.1016/j.hydromet.2006.05.001 |bibcode=2006HydMe..84...81W |url-status=dead |archive-url=https://web.archive.org/web/20110818131019/http://infolib.hua.edu.vn/Fulltext/ChuyenDe/ChuyenDe07/CDe53/59.pdf |archive-date=18 August 2011}}

A potential source of copper is polymetallic nodules, which have an estimated concentration 1.3%.{{cite journal |last1=Su |first1=Kun |last2=Ma |first2=Xiaodong |last3=Parianos |first3=John |last4=Zhao |first4=Baojun |title=Thermodynamic and Experimental Study on Efficient Extraction of Valuable Metals from Polymetallic Nodules |journal=Minerals |date=2020 |volume=10 |issue=4 |pages=360 |doi=10.3390/min10040360 |bibcode=2020Mine...10..360S |doi-access=free }}{{cite web |last1=International Seabed Authority |title=Polymetallic Nodules |url=https://isa.org.jm/files/files/documents/eng7.pdf |publisher=International Seabed Authority |access-date=8 February 2021 |archive-date=23 October 2021 |archive-url=https://web.archive.org/web/20211023145629/https://isa.org.jm/files/files/documents/eng7.pdf |url-status=dead }}

{{Plain image with caption|Ural Mining and Metallurgical Company Copper Map.svg|Flowchart of copper refining (Anode casting plant of Uralelektromed)

1. Blister copper
2. Smelting
3. Reverberatory furnace
4. Slag removal
5. Copper casting of anodes
6. Casting wheel
7. Anodes removal machine
8. Anodes take-off
9. Rail cars
10. Transportation to the tank house|650|center|top|triangle|#ccc}}

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). In 2001, a typical automobile contained 20–30 kg of copper. By 2014, the copper and copper alloy content of internal combustion engine vehicles decreased to 16.8 kg, but increased again to 24.5 kg by 2023.{{Cite web |date=May 2024 |title=Chemistry and Automobiles Driving the Future |url=https://www.americanchemistry.com/content/download/16352/file/Chemistry-and-Automobiles-2024.pdf |website=American Chemistry Counsil}} At the same time, a battery electric vehicle already contains around 91 kg of copper and copper alloys.{{Cite web |date=2024-05-15 |title=Copper can't be mined fast enough to electrify the US |url=https://news.umich.edu/copper-cant-be-mined-fast-enough-to-electrify-the-us/ |access-date=2025-04-25 |website=University of Michigan News |language=en-US}}

Like aluminium, copper is recyclable without any loss of quality, both from raw state and from manufactured products.{{Cite book|url=https://books.google.com/books?id=5_QLBwAAQBAJ&q=copper+recyclable+without+any+loss+of+quality&pg=PA249|title=The Role of Ecological Chemistry in Pollution Research and Sustainable Development|last1=Bahadir|first1=Ali Mufit|last2=Duca|first2=Gheorghe|date=2009|publisher=Springer|isbn=978-90-481-2903-4|language=en}} An estimated 80% of all copper ever mined is still in use today.{{cite web|url=http://www.copperinfo.com/environment/recycling.html|title=International Copper Association|access-date=22 July 2009|archive-date=5 March 2012|archive-url=https://web.archive.org/web/20120305203937/http://www.copperinfo.com/environment/recycling.html|url-status=dead}} In volume, copper is the third most recycled metal after iron and aluminium.{{Cite book|url=https://books.google.com/books?id=BnN3DAAAQBAJ&q=%C2%A0copper+third+most+recycled+metal+after+iron+and+aluminium&pg=PT281|title=The Periodic Table in Minutes|last=Green|first=Dan|date=2016|publisher=Quercus|isbn=978-1-68144-329-4|language=en}} {{As of|2023}}, recycled copper supplies about one-third of global demand.{{Citation|title=The World Copper Factbook 2024|author=((International Copper Study Group))|author-link=International Copper Study Group|url=https://icsg.org/download/2024-09-23-the-world-copper-factbook-2024/?wpdmdl=8185&refresh=67470bf6457501732709366&ind=66f165bba8103&filename=Factbook2024.pdf|access-date=19 December 2024|page=53|archive-date=19 December 2024|archive-url=https://web.archive.org/web/20241219053900/https://icsg.org/download/2024-09-23-the-world-copper-factbook-2024/?wpdmdl=8185&refresh=67470bf6457501732709366&ind=66f165bba8103&filename=Factbook2024.pdf|url-status=live}}

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.[http://www.copper.org/publications/newsletters/innovations/1998/06/recycle_overview.html "Overview of Recycled Copper" Copper.org]. (25 August 2010). Retrieved on 8 November 2011. Lower-purity scrap is melted to form black copper (70–90% pure, containing impurities such as iron, zinc, tin, and nickel), followed by oxidation of impurities in a converter to form blister copper (96–98% pure), which is then refined as before.{{cite book |doi=10.1002/14356007.a07_471 |chapter=Copper |title=Ullmann's Encyclopedia of Industrial Chemistry |date=2012 |last1=Lossin |first1=Adalbert |isbn=9783527303854 |edition=7th |volume=10 |page=202}}{{rp|p=202}}

Cu mining creates direct environmental impacts from tailing, overburden rocks, and abandoned mines. Tailing includes liquid waste typically sulfide rich, generating acid mine drainage. The acid in turn may leach heavy metals from surrounding soil. Overburden rocks may also leach heavy metals in areas of high rainfall. These heavy metals can accumulate in downstream farming areas and enter the food chain. Some of these metals are known carcinogens.{{Cite journal |last=Punia |first=Anita |date=January 2021 |title=Role of temperature, wind, and precipitation in heavy metal contamination at copper mines: a review |url=http://link.springer.com/10.1007/s11356-020-11580-8 |journal=Environmental Science and Pollution Research |language=en |volume=28 |issue=4 |pages=4056–4072 |doi=10.1007/s11356-020-11580-8 |pmid=33188519 |bibcode=2021ESPR...28.4056P |issn=0944-1344}}

Advocacy groups have reported that mining companies exploit local populations by corrupting local officials in parts of the Philippines.{{cite web |url=https://www.amnesty.fr/responsabilite-des-entreprises/actualites/philippines-attention-terrain-mine |publisher=Amnesty International |title=Philippines: attention, terrain miné |language=fr |trans-title=Philippines: attention, mined land |date=2016-11-09}}

Indirect impacts include

greenhouse gas emissions primarily from electricity consumed by the company, especially when sourced from fossil fuels, and from engines required for copper extraction and refinement.

The environmental cost of copper mining was estimated at 3.7 kg {{CO2}}-eq per kg of copper in 2019.{{cite web |url=https://www.mineralinfo.fr/sites/default/files/documents/2021-10/presentation_comes_20210517_com.pdf |publisher=WeeeCycling |date=2021-05-17 |language=fr |title=Les opportunités du recyclage du cuivre de haute pureté |trans-title=Opportunities for recycling high purity copper}} Codelco, a major producer in Chile, reported that in 2020 the company emitted 2.8 t {{CO2}}-eq per ton (2.8 kg {{CO2}}-eq per kg) of fine copper.{{cite web |url=https://www.codelco.com/sites/site/docs/20221206/20221206220556/annual_memory_2020.pdf |page=109 |publisher=Codelco |title=Annual Memory 2020}}

File:1953 Canadian Dime in a box of US Dimes.jpgs, which are composed of the alloy cupronickel{{cite web |title=Dime |url=http://catalog.usmint.gov/coins/proof-sets/ |archive-url=https://web.archive.org/web/20141004031452/http://catalog.usmint.gov/coins/proof-sets/ |url-status=dead |archive-date=4 October 2014 |website=US Mint |access-date=9 July 2019 }} and a pre-1968 Canadian dime, which is composed of an alloy of 80 percent silver and 20 percent copper.{{cite web |title=Pride and skill – the 10-cent coin |url=https://www.mint.ca/store/mint/about-the-mint/10-cents-5300008#.XSUUVuhKiUk |website=Royal Canadian Mint |access-date=9 July 2019}}]]

{{See also|List of copper alloys}}

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-tin bronzes with various additional metals have been use to create bells for centuries; the composition of the alloy directly affects the tone and mechanical characteristics of the instrument.{{Cite journal |last1=Audy |first1=K. |last2=Audy |first2=J. |date=2006-06-01 |title=Analysis of the Bell-Making Process from the Middle Ages to Recent Times |url=https://www.degruyterbrill.com:443/document/doi/10.1515/pm-2006-0071/html |journal=Practical Metallography |language=en |volume=43 |issue=6 |pages=271–292 |doi=10.1515/pm-2006-0071 |issn=2195-8599}} 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.{{cite web|url=http://www.utilisegold.com/jewellery_technology/colours/colour_alloys/ |access-date=6 June 2009 |title=Gold Jewellery Alloys |publisher=World Gold Council |url-status=dead |archive-url=https://web.archive.org/web/20090414151414/http://www.utilisegold.com/jewellery_technology/colours/colour_alloys |archive-date=14 April 2009}} Some lead-free solders consist of tin alloyed with a small proportion of copper and other metals.[http://www.balverzinn.com/downloads/Solder_Sn97Cu3.pdf Balver Zinn Solder Sn97Cu3] {{webarchive |url=https://web.archive.org/web/20110707210148/http://www.balverzinn.com/downloads/Solder_Sn97Cu3.pdf |date=7 July 2011 }}. (PDF) . balverzinn.com. Retrieved on 8 November 2011.

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,{{cite web |last1=Deane |first1=D. V. |title=Modern Coinage Systems |url=https://www.britnumsoc.org/publications/Digital%20BNJ/pdfs/1968_BNJ_37_20.pdf |website=British Numismatic Society |access-date=1 July 2019}} 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.{{cite web |title=What is 90% Silver? |url=https://www.apmex.com/education/bullion/what-is-90-percent-silver-junk-silver |website=American Precious Metals Exchange (APMEX) |access-date=1 July 2019 |archive-date=28 July 2020 |archive-url=https://web.archive.org/web/20200728210159/https://www.apmex.com/education/bullion/what-is-90-percent-silver-junk-silver |url-status=dead }} 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.{{Cite book|url=https://books.google.com/books?id=8C7pXhnqje4C|title=Corrosion Tests and Standards|publisher=ASTM International|page=368|language=en|year=2005}} 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.{{cite journal|last=Oguchi|first=Hachiro|date=1983|title=Japanese Shakudō: its history, properties and production from gold-containing alloys|journal=Gold Bulletin|volume=16|issue=4|pages=125–132|doi=10.1007/BF03214636|doi-access=free}}

{{Clear}}

File:CopperIoxide.jpg]]

{{Main|Copper compounds}}

Copper forms a rich variety of compounds, usually with oxidation states +1 and +2, which are often called cuprous and cupric, respectively. Copper compounds promote or catalyse numerous chemical and biological processes.{{cite journal |last1=Trammell |first1=Rachel |last2=Rajabimoghadam |first2=Khashayar |last3=Garcia-Bosch |first3=Isaac |title=Copper-Promoted Functionalization of Organic Molecules: from Biologically Relevant Cu/O2 Model Systems to Organometallic Transformations|journal=Chemical Reviews |volume=119 |issue=4 |pages=2954–3031 |date=30 January 2019 |doi=10.1021/acs.chemrev.8b00368|pmid=30698952 |pmc=6571019 }}

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,{{ cite book | first1 = A. F. | last1 = Wells | title = Structural Inorganic Chemistry | edition = 5th | year = 1984 | publisher = Oxford University Press | isbn = 978-0-19-965763-6 | pages = 1142–1145 }} important examples include copper(I) sulfide ({{chem2|Cu2S}}) and copper monosulfide ({{chem2|CuS}}).{{Greenwood&Earnshaw2nd|pages=1181}}

Cuprous halides with fluorine, chlorine, bromine, and iodine are known, as are cupric halides with fluorine, chlorine, and bromine. Attempts to prepare copper(II) iodide yield only copper(I) iodide and iodine.{{cite book |last1=Holleman |first1=A.F. |last2=Wiberg |first2=N. |title=Inorganic Chemistry |date=2001 |publisher=Academic Press |location=San Diego |isbn=978-0-12-352651-9}}

:2 Cu²⁺ + 4 I⁻ → 2 CuI + I₂

File:Tetramminkupfer(II)-sulfat-Monohydrat Kristalle.png.]]

Copper forms coordination complexes with ligands. In aqueous solution, copper(II) exists as {{chem|[Cu|(H|2|O)|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.{{cn|date=May 2025}} A simplified equation is: File:Cu-pourbaix-diagram.svg

:Cu²⁺ + 2 OH⁻ → Cu(OH)₂

Aqueous ammonia results in the same precipitate. Upon adding excess ammonia, the precipitate dissolves, forming tetraamminecopper(II):

:{{chem|Cu|(H|2|O)|4|(OH)|2}} + 4 NH₃ → {{chem|[Cu|(H|2|O)|2|(N|H|3|)|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.{{cite book|chapter-url = https://books.google.com/books?id=cItuoO9zSjkC&pg=PA623|page = 623|chapter = Nonsystematic (Contact) Fungicides|title = Ullmann's Agrochemicals|isbn = 978-3-527-31604-5|author1 = Wiley-Vch|date = 2 April 2007| publisher=Wiley }}

File:Tetraamminediaquacopper(II)-3D-balls.png of the complex [Cu(NH₃)₄(H₂O)₂]²⁺, illustrating the octahedral coordination geometry common for copper(II)]]

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.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}} Schweizer's reagent and related complexes with ethylenediamine and other amines dissolve cellulose.{{cite journal | last1 = Saalwächter | first1 = Kay | last2 = Burchard | first2 = Walther | last3 = Klüfers | first3 = Peter | last4 = Kettenbach | first4 = G. | last5 = Mayer | first5 = Peter | last6 = Klemm | first6 = Dieter | last7 = Dugarmaa | first7 = Saran | year = 2000 | title = Cellulose Solutions in Water Containing Metal Complexes | journal = Macromolecules | volume = 33 | issue = 11| pages = 4094–4107 | doi = 10.1021/ma991893m | bibcode = 2000MaMol..33.4094S | citeseerx = 10.1.1.951.5219 }} Amino acids such as cystine form very stable chelate complexes with copper(II)Deodhar, S., Huckaby, J., Delahoussaye, M. and DeCoster, M.A., 2014, August. High-aspect ratio bio-metallic nanocomposites for cellular interactions. In IOP Conference Series: Materials Science and Engineering (Vol. 64, No. 1, p. 012014). https://iopscience.iop.org/article/10.1088/1757-899X/64/1/012014/meta.Kelly, K.C., Wasserman, J.R., Deodhar, S., Huckaby, J. and DeCoster, M.A., 2015. Generation of scalable, metallic high-aspect ratio nanocomposites in a biological liquid medium. Journal of Visualized Experiments, (101), p.e52901. https://www.jove.com/t/52901/generation-scalable-metallic-high-aspect-ratio-nanocomposites.Karan, A., Darder, M., Kansakar, U., Norcross, Z. and DeCoster, M.A., 2018. Integration of a Copper-Containing Biohybrid (CuHARS) with Cellulose for Subsequent Degradation and Biomedical Control. International journal of environmental research and public health, 15(5), p.844. https://www.mdpi.com/1660-4601/15/5/844 including in the form of metal-organic biohybrids (MOBs). Many wet-chemical tests for copper ions exist, one involving potassium ferricyanide, which gives a red-brown precipitate with copper(II) salts.{{Cite web |date=2018-04-03 |title=Characteristic Reactions of Copper Ions (Cu²⁺) |url=https://chem.libretexts.org/Bookshelves/Analytical_Chemistry/Supplemental_Modules_(Analytical_Chemistry)/Qualitative_Analysis/Characteristic_Reactions_of_Select_Metal_Ions/Characteristic_Reactions_of_Copper_Ions_(Cu) |access-date=2024-05-27 |website=Chemistry LibreTexts |language=en}}

{{Main|Organocopper compound}}

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;"Modern Organocopper Chemistry" Norbert Krause, Ed., Wiley-VCH, Weinheim, 2002. {{ISBN|978-3-527-29773-3}}. 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{{cite journal|last1=Berná|first1=José|last2=Goldup|first2=Stephen|last3=Lee|first3=Ai-Lan|last4=Leigh|first4=David|last5=Symes|first5=Mark|last6=Teobaldi|first6=Gilberto|last7=Zerbetto|first7=Fransesco|title=Cadiot–Chodkiewicz Active Template Synthesis of Rotaxanes and Switchable Molecular Shuttles with Weak Intercomponent Interactions|journal=Angewandte Chemie|date=26 May 2008|volume=120|issue=23|pages=4464–4468|doi=10.1002/ange.200800891|bibcode=2008AngCh.120.4464B}} and the Sonogashira coupling.{{cite journal|title = The Sonogashira Reaction: A Booming Methodology in Synthetic Organic Chemistry|author = Rafael Chinchilla|author2 = Carmen Nájera|name-list-style = amp|journal = Chemical Reviews|date = 2007|volume = 107|issue = 3|pages = 874–922|doi = 10.1021/cr050992x|pmid = 17305399}} Conjugate addition to enones{{cite journal|date=1986 |title=An Addition of an Ethylcopper Complex to 1-Octyne: (E)-5-Ethyl-1,4-Undecadiene |journal=Organic Syntheses |volume=64 |page=1 |doi=10.15227/orgsyn.064.0001 }} and carbocupration of alkynes{{cite journal |last1=Kharasch |first1=M.S. |last2=Tawney |first2=P.O. |date=1941|title=Factors Determining the Course and Mechanisms of Grignard Reactions. II. The Effect of Metallic Compounds on the Reaction between Isophorone and Methylmagnesium Bromide |journal=Journal of the American Chemical Society |volume=63 |issue=9 |pages=2308–2316 |doi=10.1021/ja01854a005|bibcode=1941JAChS..63.2308K }} 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.{{cite journal|last1= Imai |first1= Sadako |last2= Fujisawa |first2= Kiyoshi |last3= Kobayashi |first3= Takako |last4= Shirasawa |first4= Nobuhiko |last5= Fujii |first5= Hiroshi |last6= Yoshimura |first6= Tetsuhiko |last7= Kitajima |first7= Nobumasa |last8= Moro-oka |first8= Yoshihiko |title= ⁶³Cu NMR Study of Copper(I) Carbonyl Complexes with Various Hydrotris(pyrazolyl)borates: Correlation between 63Cu Chemical Shifts and CO Stretching Vibrations|journal= Inorganic Chemistry |date= 1998| volume =37|pages=3066–3070|doi=10.1021/ic970138r|issue=12}}

Copper(III) is most often found in oxides. A simple example is potassium cuprate, KCuO₂, a blue-black solid.{{cite book|chapter=Potassium Cuprate (III)|title=Handbook of Preparative Inorganic Chemistry|edition=2nd|editor=G. Brauer|publisher=Academic Press|year=1963|location=NY|volume=1|page=1015}} 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{{cite journal|author1=Schwesinger, Reinhard |author2=Link, Reinhard |author3=Wenzl, Peter |author4=Kossek, Sebastian |title=Anhydrous phosphazenium fluorides as sources for extremely reactive fluoride ions in solution|doi=10.1002/chem.200500838|year=2006|journal=Chemistry: A European Journal|volume=12|issue=2|pages=438–45 |pmid=16196062}} 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.

Some copper proteins form oxo complexes, which, in extensively studied synthetic analog systems, feature copper(III).{{Cite journal |last1=Mirica |first1=Liviu M. |last2=Ottenwaelder |first2=Xavier |last3=Stack |first3=T. Daniel P. |date=2004-02-01 |title=Structure and Spectroscopy of Copper−Dioxygen Complexes |url=https://pubs.acs.org/doi/10.1021/cr020632z |journal=Chemical Reviews |language=en |volume=104 |issue=2 |pages=1013–1046 |doi=10.1021/cr020632z |pmid=14871148 |issn=0009-2665|url-access=subscription }}{{cite journal |last1=Lewis |first1=E.A. |last2=Tolman |first2=W.B. |date=2004 |title=Reactivity of Dioxygen-Copper Systems |journal=Chemical Reviews |volume=104 |pages=1047–1076 |doi=10.1021/cr020633r |issue=2 |pmid=14871149}} With tetrapeptides, purple-colored copper(III) complexes are stabilized by the deprotonated amide ligands.{{cite journal |last1=McDonald |first1=M.R. |last2=Fredericks |first2=F.C. |last3=Margerum |first3=D.W. |date=1997 |title=Characterization of Copper(III)–Tetrapeptide Complexes with Histidine as the Third Residue |journal=Inorganic Chemistry |volume=36 |pages=3119–3124|doi=10.1021/ic9608713|pmid=11669966 |issue=14}}

Complexes of copper(III) are also found as intermediates in reactions of organocopper compounds, for example in the Kharasch–Sosnovsky reaction.{{Greenwood&Earnshaw2nd|page=1187}}{{ cite journal | first1 = A. | last1 = Hickman | first2 = M. | last2 = Sanford | title = High-valent organometallic copper and palladium in catalysis | journal = Nature | volume = 484 | pages = 177–185 | year = 2012 | issue = 7393 | doi = 10.1038/nature11008 | pmid = 22498623 | pmc = 4384170 | bibcode = 2012Natur.484..177H }}{{ cite journal | title = Well-defined organometallic Copper(III) complexes: Preparation, characterization and reactivity | first1 = He | last1 = Liu | first2 = Qilong | last2 = Shen | journal = Coord. Chem. Rev. | volume = 442 | year = 2021 | page = 213923 | doi = 10.1016/j.ccr.2021.213923}}

A timeline of copper illustrates how this metal has advanced human civilization for the past 11,000 years.A Timeline of Copper Technologies, Copper Development Association, https://www.copper.org/education/history/timeline/

{{Main|Copper Age}}

File:Minoan copper ingot from Zakros, Crete.jpg from Zakros, Crete, shaped in the form of an animal skin (oxhide) typical in that era]]

File:ReconstructedOetziAxe.jpg Era included copper, such as the blade of this replica of Ötzi's axe.]]

File:Chrysocolla Timna 070613.jpg) in Cambrian sandstone from Chalcolithic mines in the Timna Valley, southern Israel]]

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;{{cite web|url=http://www.csa.com/discoveryguides/copper/overview.php|title=CSA – Discovery Guides, A Brief History of Copper|publisher=Csa.com|access-date=12 September 2008|archive-date=3 February 2015|archive-url=https://web.archive.org/web/20150203154021/http://www.csa.com/discoveryguides/copper/overview.php|url-status=dead}} a copper pendant was found in northern Iraq that dates to 8700 BC.{{cite book|page = 56|title = Jewelrymaking through History: an Encyclopedia|publisher= Greenwood Publishing Group|date = 2007|isbn = 978-0-313-33507-5|author = Rayner W. Hesse}}No primary source is given in that book. Evidence suggests that gold and meteoric iron (but not smelted iron) were the only metals used by humans before copper.{{cite web|url=http://elements.vanderkrogt.net/element.php?sym=Cu|title=Copper|publisher=Elements.vanderkrogt.net|access-date=12 September 2008}} 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 {{Circa|7500 BC}}.{{cite book|last=Renfrew|first=Colin|author-link=Colin Renfrew, Baron Renfrew of Kaimsthorn|title=Before civilization: the radiocarbon revolution and prehistoric Europe|url=https://books.google.com/books?id=jJhHPgAACAAJ|access-date=21 December 2011|date=1990|publisher=Penguin|isbn=978-0-14-013642-5}}

Copper smelting was independently invented in different places. The earliest evidence of lost-wax casting copper comes from an amulet found in Mehrgarh, Pakistan, and is dated to 4000 BC.{{Cite journal |last1=Thoury |first1=M. |last2=Mille |first2=B. |last3=Séverin-Fabiani |first3=T. |last4=Robbiola |first4=L. |last5=Réfrégiers |first5=M. |last6=Jarrige |first6=J.-F. |last7=Bertrand |first7=L. |date=2016-11-15 |title=High spatial dynamics-photoluminescence imaging reveals the metallurgy of the earliest lost-wax cast object |journal=Nature Communications |volume=7 |pages=13356 |doi=10.1038/ncomms13356 |issn=2041-1723 |pmc=5116070 |pmid=27843139|bibcode=2016NatCo...713356T }} Investment casting was invented in 4500–4000 BC in Southeast Asia Smelting 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.{{cite news|author = Cowen, R.|url = http://www.geology.ucdavis.edu/~cowen/~GEL115/115CH3.html|title = Essays on Geology, History, and People: Chapter 3: Fire and Metals|access-date = 7 July 2009|archive-date = 10 May 2008|archive-url = https://web.archive.org/web/20080510150436/http://www.geology.ucdavis.edu/~cowen/~GEL115/115CH3.html|url-status = dead}} Carbon dating has established mining at Alderley Edge in Cheshire, UK, at 2280 to 1890 BC.{{cite book|author=Timberlake, S.|title=The Archaeology of Alderley Edge: Survey, excavation and experiment in an ancient mining landscape|author2=Prag A.J.N.W.|date=2005|publisher=John and Erica Hedges Ltd.|location=Oxford|page=396|doi=10.30861/9781841717159|isbn=9781841717159|name-list-style=amp}}

Ötzi the Iceman, a male dated from 3300 to 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.{{cite web|title=CSA – Discovery Guides, A Brief History of Copper|url=http://www.csa.com/discoveryguides/copper/overview.php|work=CSA Discovery Guides|access-date=29 April 2011|archive-date=3 February 2015|archive-url=https://web.archive.org/web/20150203154021/http://www.csa.com/discoveryguides/copper/overview.php|url-status=dead}} Experience with copper has assisted the development of other metals; in particular, copper smelting likely led to the discovery of iron smelting.

File:Copper_knife,_spearpoints,_awls,_and_spud,_Late_Archaic_period,_Wisconsin,_3000_BC-1000_BC_-_Wisconsin_Historical_Museum_-_DSC03436.JPG of North America, which may have existed from approximately 9500–5400 years before present]]

Production in the Old Copper Complex in Michigan and Wisconsin is dated between 6500 and 3000 BC.{{Cite journal |last1=Pompeani |first1=David P |last2=Steinman |first2=Byron A |last3=Abbott |first3=Mark B |last4=Pompeani |first4=Katherine M |last5=Reardon |first5=William |last6=DePasqual |first6=Seth |last7=Mueller |first7=Robin H |title=On the Timing of the Old Copper Complex in North America: A Comparison of Radiocarbon Dates from Different Archaeological Contexts |date=April 2021 |url=https://www.cambridge.org/core/product/identifier/S0033822221000072/type/journal_article |journal=Radiocarbon |language=en |volume=63 |issue=2 |pages=513–531 |doi=10.1017/RDC.2021.7 |bibcode=2021Radcb..63..513P |s2cid=233029733 |issn=0033-8222|url-access=subscription }}Pleger, Thomas C. "A Brief Introduction to the Old Copper Complex of the Western Great Lakes: 4000–1000 BC", [https://books.google.com/books?id=6NUQNQAACAAJ 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. [https://books.google.com/books?id=awsA08oYoskC&pg=PA709 Archaic Societies: Diversity and Complexity Across the Midcontinent], SUNY Press, 2009 {{ISBN|1-4384-2701-8}}. A copper spearpoint found in Wisconsin has been dated to 6500 BC. Copper usage by the indigenous peoples of the Old Copper Complex from the Great Lakes region of North America has been radiometrically dated to as far back as 7500 BC.{{Cite journal |last1=Bebber |first1=Michelle R. |last2=Buchanan |first2=Briggs |last3=Holland-Lulewicz |first3=Jacob |date=2022-04-26 |title=Refining the chronology of North America's copper using traditions: A macroscalar approach via Bayesian modeling |journal=PLOS ONE |language=en |volume=17 |issue=4 |pages=e0266908 |doi=10.1371/journal.pone.0266908 |issn=1932-6203 |pmc=9041870 |pmid=35472064 |bibcode=2022PLoSO..1766908B |doi-access=free }}{{Cite journal |last=Malakoff |first=David |date=2021-03-19 |title=Ancient Native Americans were among the world's first coppersmiths |url=http://dx.doi.org/10.1126/science.abi6135 |journal=Science |doi=10.1126/science.abi6135 |s2cid=233663403 |issn=0036-8075|url-access=subscription }} Indigenous peoples of North America around the Great Lakes may have also been mining copper during this time, making it one of the oldest known examples of copper extraction in the world.{{Cite journal |last1=Pompeani |first1=David P. |last2=Abbott |first2=Mark B. |last3=Steinman |first3=Byron A. |last4=Bain |first4=Daniel J. |date=2013-05-14 |title=Lake Sediments Record Prehistoric Lead Pollution Related to Early Copper Production in North America |url=http://dx.doi.org/10.1021/es304499c |journal=Environmental Science & Technology |volume=47 |issue=11 |pages=5545–5552 |doi=10.1021/es304499c |pmid=23621800 |bibcode=2013EnST...47.5545P |issn=0013-936X|url-access=subscription }} There is evidence from prehistoric lead pollution from lakes in Michigan that people in the region began mining copper {{Circa|6000 BC}}. Evidence suggests that utilitarian copper objects fell increasingly out of use in the Old Copper Complex of North America during the Bronze Age and a shift towards an increased production of ornamental copper objects occurred.{{Cite journal |last1=Bebber |first1=Michelle R. |last2=Eren |first2=Metin I. |date=2018-10-01 |title=Toward a functional understanding of the North American Old Copper Culture "technomic devolution" |journal=Journal of Archaeological Science |language=en |volume=98 |pages=34–44 |doi=10.1016/j.jas.2018.08.001 |bibcode=2018JArSc..98...34B |s2cid=134060339 |issn=0305-4403|doi-access=free }}

{{Main|Bronze Age}}

File:Egyptian - Blue Faience Saucer and Stand - Walters 481608 - Top.jpg" faience saucer and stand from the Bronze Age, New Kingdom of Egypt (1400–1325 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.{{Cite book|title=Chinese Studies in the History and Philosophy of Science and Technology|last=Dainian|first=Fan|pages=228}} 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.{{Cite book|title=Epigenetics: The Death of the Genetic Theory of Disease Transmission|last=Wallach|first=Joel}} Bronze artifacts from the Vinča culture date to 4500 BC.{{cite web | url = http://antiquity.ac.uk/ant/087/ant0871030.htm | title = Tainted ores and the rise of tin bronzes in Eurasia, c. 6500 years ago | first1 = Miljana | last1 = Radivojević | first2 = Thilo | last2 = Rehren | publisher = Antiquity Publications Ltd | date = December 2013 | access-date = 5 February 2014 | archive-date = 5 February 2014 | archive-url = https://archive.today/20140205001504/http://antiquity.ac.uk/ant/087/ant0871030.htm | url-status = dead }} Sumerian and Egyptian artifacts of copper and bronze alloys date to 3000 BC.{{cite book|pages = 13, 48–66|title = Encyclopaedia of the History of Technology|author = McNeil, Ian |publisher = Routledge|date = 2002|location = London; New York|isbn = 978-0-203-19211-5}} Egyptian Blue, or cuprorivaite (calcium copper silicate) is a synthetic pigment that contains copper and started being used in ancient Egypt around 3250 BC.{{Cite book |last1=Eastaugh |first1=Nicholas |last2=Walsh |first2=Valentine |last3=Chaplin |first3=Tracey |last4=Siddall |first4=Ruth |date=2013-06-17 |title=Pigment Compendium: Optical Microscopy of Historical Pigments |url=http://dx.doi.org/10.4324/9780080454573 |doi=10.4324/9780080454573|isbn=9781136373794 }} The manufacturing process of Egyptian blue was known to the Romans, but by the fourth century AD the pigment fell out of use and the secret to its manufacturing process became lost. The Roman Vitruvius said in the first century BC that the blue pigment was made from copper minerals or bronze, lime, and a flux like natron and this basic recipe has been confirmed in modern times.{{Cite journal |last1=Mazzocchin |first1=Gian Antonio |last2=Rudello |first2=Danilo |last3=Bragato |first3=Carlo |last4=Agnoli |first4=Francesca |date=January 2004 |title=A short note on Egyptian blue |url=https://linkinghub.elsevier.com/retrieve/pii/S1296207403001109 |journal=Journal of Cultural Heritage |language=en |volume=5 |issue=1 |pages=129–133 |doi=10.1016/j.culher.2003.06.004}}

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.

File:Venus symbol (fixed width).svg the symbol for copper was also the symbol for the goddess and planet Venus.]]

File:TimnaChalcolithicMine.JPG, Negev Desert, Israel]]

In Greece, copper was known by the name {{transliteration|grc|chalkos}} (χαλκός). It was an important resource for the Romans, Greeks and other ancient peoples. In Roman times, it was known as aes Cyprium, {{Lang|la|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, the source of copper, 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, both because of the connection to the goddess and because Venus was the brightest heavenly body after the Sun and Moon and so corresponded to the most lustrous and desirable metal after gold and silver.{{cite journal|title = The Nomenclature of Copper and its Alloys|author = Rickard, T.A. |journal = Journal of the Royal Anthropological Institute|volume = 62|pages = 281–290 |date = 1932|jstor = 2843960|doi = 10.2307/2843960}}

Copper was first mined in ancient Britain as early as 2100 BC. Mining at the largest of these mines, the Great Orme, continued into the late Bronze Age. Mining seems to have been largely restricted to supergene ores, which were easier to smelt. The rich copper deposits of Cornwall seem to have been largely untouched, in spite of extensive tin mining in the region, for reasons likely social and political rather than technological.{{cite journal |last1=Timberlake |first1=Simon |title=New ideas on the exploitation of copper, tin, gold, and lead ores in Bronze Age Britain: The mining, smelting, and movement of metal |journal=Materials and Manufacturing Processes |date=11 June 2017 |volume=32 |issue=7–8 |pages=709–727 |doi=10.1080/10426914.2016.1221113|s2cid=138178474 }}

Copper was the most extensively used metal among natives of North America, with evidence for use going back 7000 years.{{Cite journal |last=Ehrhardt |first=Kathleen L. |date=September 2009 |title=Copper Working Technologies, Contexts of Use, and Social Complexity in the Eastern Woodlands of Native North America |url=http://link.springer.com/10.1007/s10963-009-9020-8 |journal=Journal of World Prehistory |language=en |volume=22 |issue=3 |pages=213–235 |doi=10.1007/s10963-009-9020-8 |issn=0892-7537}}

Native copper is known to have been extracted from sites on Isle Royale with primitive stone tools between 800 and 1600 AD.{{cite journal|title = The State of Our Knowledge About Ancient Copper Mining in Michigan|journal = The Michigan Archaeologist|volume = 41|page = 119|author = Martin, Susan R.|date = 1995|url = http://www.ramtops.co.uk/copper.html|issue = 2–3|url-status=dead|archive-url = https://web.archive.org/web/20160207073036/http://www.ramtops.co.uk/copper.html|archive-date = 7 February 2016}} Copper, probably from pure nuggets found in the Great Lakes area, was worked by repeated hammering and annealing in the North American city of Cahokia (near modern day Missouri) around 1000–1300 AD.{{Cite journal |last1=Chastain |first1=Matthew L. |last2=Deymier-Black |first2=Alix C. |last3=Kelly |first3=John E. |last4=Brown |first4=James A. |last5=Dunand |first5=David C. |date=2011-07-01 |title=Metallurgical analysis of copper artifacts from Cahokia |url=https://www.sciencedirect.com/science/article/pii/S0305440311000793 |journal=Journal of Archaeological Science |language=en |volume=38 |issue=7 |pages=1727–1736 |doi=10.1016/j.jas.2011.03.004 |bibcode=2011JArSc..38.1727C |issn=0305-4403|url-access=subscription }} There are several exquisite copper plates, known as the Mississippian copper plates that have been found in North America in the area around Cahokia dating from this time period (1000–1300 AD).

File:Spiro_Wulfing_and_Etowah_repousse_plates_HRoe_2012.jpg from North America were produced in this style from around 800–1600 AD.]]

In South America a copper mask dated to 1000 BC found in the Argentinian Andes is the oldest known copper artifact discovered in the Andes.{{Cite journal |last1=Cortés |first1=Leticia Inés |last2=Scattolin |first2=María Cristina |date=June 2017 |title=Ancient metalworking in South America: a 3000-year-old copper mask from the Argentinian Andes |journal=Antiquity |language=en |volume=91 |issue=357 |pages=688–700 |doi=10.15184/aqy.2017.28 |s2cid=53068689 |issn=0003-598X|doi-access=free |hdl=11336/39789 |hdl-access=free }} Peru has been considered the origin for early copper metallurgy in pre-Columbian America, but the copper mask from Argentina suggests that the Cajón del Maipo of the southern Andes was another important center for early copper workings in South America. Copper metallurgy in Peru dates to around 500 BC with larger scale production beginning around 900 AD as part of the rise of the Sican culture in northern Peru. The production continued through a series of conquests by the Chimor and Inca cultures, ending with the Spanish conquest in 1532.{{Cite journal |last1=Shimada |first1=Izumi |last2=Merkel |first2=John F. |date=1991 |title=Copper-Alloy Metallurgy in Ancient Peru |url=https://www.jstor.org/stable/24936982 |journal=Scientific American |volume=265 |issue=1 |pages=80–87 |doi=10.1038/scientificamerican0791-80 |jstor=24936982 |bibcode=1991SciAm.265a..80S |issn=0036-8733}}

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.{{cite journal|doi = 10.1126/science.272.5259.246|title = History of Ancient Copper Smelting Pollution During Roman and Medieval Times Recorded in Greenland Ice|pages = 246–249 (247f.)|date = 1996|last1 = Hong|first1 = S.|last2 = Candelone|first2 = J.-P.|issue = 5259|last3 = Patterson|first3 = C.C.|last4 = Boutron|first4 = C.F.|journal = Science|volume = 272|bibcode = 1996Sci...272..246H|s2cid = 176767223}}{{cite journal|last = de Callataÿ|first = François|date = 2005|title = The Graeco-Roman Economy in the Super Long-Run: Lead, Copper, and Shipwrecks|journal = Journal of Roman Archaeology|volume = 18|pages = 361–372 (366–369)|doi = 10.1017/S104775940000742X|s2cid = 232346123}}

The gates of the Temple of Jerusalem used Corinthian bronze, a copper, silver, and gold alloy treated with depletion gilding which successively removes oxidized copper to create a gold surface coat. The process was most prevalent in Alexandria, where alchemy, inspired by the chemical treatment resulting in gold appearance, is thought to have begun.{{Cite journal |last=Jacobson |first=David M |date=June 2000 |title=Corinthian bronze and the gold of the alchemists |url=https://link.springer.com/10.1007/BF03216582 |journal=Gold Bulletin |language=en |volume=33 |issue=2 |pages=60–66 |doi=10.1007/BF03216582 |issn=0017-1557}}

File:AngleseyCopperStream.jpg affecting the stream running from the disused Parys Mountain copper mines]]

File:Copper Pot.jpg from Norway made from Swedish copper]]

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.{{cite book|url = https://books.google.com/books?id=4yp-x3TzDnEC&pg=PA60|page = 60|title = Mining in World History|isbn = 978-1-86189-173-0|author1 = Lynch, Martin|year=2004| publisher=Reaktion Books }} It was referred to as the nation's treasury; Sweden had a copper backed currency.{{cite web|title=Gold: prices, facts, figures and research: A brief history of money|url=http://www.galmarley.com/FAQs_pages/monetary_history_faqs.htm#Scandinavian%20copper%20money|access-date=22 April 2011}}

File:Viipuri - Viborg.jpg of the city of Vyborg at the turn of the 17th and 18th centuries. The year 1709 carved on the printing plate.]]

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.{{cite web|title = Copper and Brass in Ships|url = https://www.copper.org/education/history/60centuries/industrial_age/copperand.html|access-date = 6 September 2016}} The Norddeutsche Affinerie in Hamburg was the first modern electroplating plant, starting its production in 1876.{{cite journal|doi = 10.1002/adem.200400403|title = Process Optimization in Copper Electrorefining|date = 2004|author = Stelter, M.|journal = Advanced Engineering Materials|volume = 6|issue = 7|pages=558–562|last2 = Bombach|first2 = H.| s2cid=138550311 }}

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.{{cite book |last1=Gardner |first1=E. D. |display-authors=et al |title=Copper Mining in North America |date=1938 |publisher=U. S. Bureau of Mines |location=Washington, D. C. |url=https://digital.library.unt.edu/ark:/67531/metadc12571/ |access-date=19 March 2019}} 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 Southwest 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.{{cite book |last1=Hyde |first1=Charles |title=Copper for America, the United States Copper Industry from Colonial Times to the 1990s |date=1998 |publisher=University of Arizona Press |location=Tucson, Arizona |isbn=0-8165-1817-3 |page=passim}}

Flash smelting was developed by Outokumpu in Finland and first applied at Harjavalta in 1949; the energy-efficient process accounts for 50% of the world's primary copper production.{{cite web|url = http://www.outokumpu.com/files/Technology/Documents/Newlogobrochures/FlashSmelting.pdf|archive-url = https://web.archive.org/web/20110724043222/http://www.outokumpu.com/files/Technology/Documents/Newlogobrochures/FlashSmelting.pdf|archive-date = 24 July 2011|title = Outokumpu Flash Smelting|publisher = Outokumpu|page = 2}}

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.{{cite journal |author=Karen A. Mingst |date=1976 |title=Cooperation or illusion: an examination of the intergovernmental council of copper exporting countries |journal=International Organization |volume=30 |issue=2 |pages=263–287 |doi=10.1017/S0020818300018270|s2cid=154183817 }}

In 2008, China became the world's largest importer of copper and has continued to be as of at least 2023.{{Cite book |last=Massot |first=Pascale |title=China's Vulnerability Paradox: How the World's Largest Consumer Transformed Global Commodity Markets |date=2024 |publisher=Oxford University Press |isbn=978-0-19-777140-2 |location=New York, NY, United States of America |pages=}}{{Rp|page=187}}

Total world production in 2023 is expected to be almost 23 million metric tons.{{Cite web |last=GlobalData |date=2023-11-17 |title=Global copper supply in 2023 will be supported by increased output from the DRC, Peru, and Chile |url=https://www.mining-technology.com/analyst-comment/global-copper-supply-2023/ |access-date=2023-12-22 |website=Mining Technology |language=en-US}} Copper demand is increasing due to the ongoing energy transition to electricity.{{Cite web |last=Woods |first=Bob |date=2023-09-27 |title=Copper is critical to energy transition. The world is falling way behind on producing enough |url=https://www.cnbc.com/2023/09/27/copper-is-critical-to-climate-the-world-is-way-behind-on-production.html |access-date=2023-12-22 |website=CNBC |language=en}} China accounts for over half the demand.{{Cite web |title=China drives copper to 4-month low, raising global economic alarms |url=https://asia.nikkei.com/Business/Markets/Commodities/China-drives-copper-to-4-month-low-raising-global-economic-alarms2 |access-date=2023-12-22 |website=Nikkei Asia |language=en-GB}}

{{See also| Copper in renewable energy}}

File:Kupferfittings 4062.jpg File:Very large copper seal end cap.jpg

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.{{Cite web|url=http://www.boatus.com/magazine/2012/february/copper.asp|title=Is Copper Bottom Paint Sinking?|website=BoatUS Magazine|author=Ryck Lydecker|access-date=2016-06-03|archive-date=1 August 2020|archive-url=https://web.archive.org/web/20200801090801/https://www.boatus.com/magazine/2012/february/copper.asp|url-status=dead}} A small part of the copper supply is used for nutritional supplements and fungicides in agriculture.{{cite web|title = Copper|publisher = American Elements|date = 2008|url = http://www.americanelements.com/cu.html|access-date = 12 July 2008|archive-date = 8 June 2008|archive-url = https://web.archive.org/web/20080608225006/http://www.americanelements.com/cu.html|url-status = dead}} Pure copper ductile and weak and high friction between the Cu chips and the cutting tool makes machining of copper difficult; alloys are preferred for good machinability.{{Cite book |last1=Zheng |first1=Hongyu |chapter-url=http://link.springer.com/10.1007/978-1-4471-4670-4_2 |title=Handbook of Manufacturing Engineering and Technology |last2=Liu |first2=Kui |date=2015 |publisher=Springer London |isbn=978-1-4471-4669-8 |editor-last=Nee |editor-first=Andrew Y. C. |location=London |pages=899–939 |language=en |chapter=Machinability of Engineering Materials |doi=10.1007/978-1-4471-4670-4_2}}

{{Main| Copper 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.Pops, Horace, 2008, "Processing of wire from antiquity to the future", Wire Journal International, June, pp. 58–66The Metallurgy of Copper Wire, http://www.litz-wire.com/pdf%20files/Metallurgy_Copper_Wire.pdf {{Webarchive|url=https://web.archive.org/web/20130901142501/http://www.litz-wire.com/pdf%20files/Metallurgy_Copper_Wire.pdf |date=1 September 2013 }} Copper wire is used in power generation, power transmission, power distribution, telecommunications, electronics circuitry, and countless types of electrical equipment.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. Electrical wiring is the most important market for the copper industry.{{cite web|url=http://www.chemistryexplained.com/elements/C-K/Copper.html |title=Copper, Chemical Element – Overview, Discovery and naming, Physical properties, Chemical properties, Occurrence in nature, Isotopes |publisher=Chemistryexplained.com |access-date=16 October 2012}} 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.Joseph, Günter, 1999, Copper: Its Trade, Manufacture, Use, and Environmental Status, edited by Kundig, Konrad J.A., ASM International, p.348 Many electrical devices rely on copper wiring because of its multitude of 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, and ease of installation.{{Cite book |title=Electrical engineer's reference book |date=1985 |publisher=Butterworths |isbn=978-1-4831-0263-4 |editor-last=Laughton |editor-first=Michael A. |edition=14 |location=Guildford |editor-last2=Say |editor-first2=Maurice G.}}{{rp|5.3}}

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 but improper design resulted in fire hazards.{{Cite web|url=https://www.heimer.com/Inspection-Information/Aluminum-Wiring.html|title=Aluminum Wiring Hazards and Pre-Purchase Inspections.|website=www.heimer.com|access-date=2016-06-03|archive-date=28 May 2016|archive-url=https://web.archive.org/web/20160528104324/http://www.heimer.com/Inspection-Information/Aluminum-Wiring.html|url-status=dead}}{{cite web |title=Repairing aluminum wiring |url=https://www.cpsc.gov/pagefiles/118856/516.pdf |website=U.S. Consumer Product Safety Commission |access-date=23 December 2023 |archive-url=https://web.archive.org/web/20161225171612/https://www.cpsc.gov/pagefiles/118856/516.pdf |archive-date=25 December 2016 |page=1 |quote=A national survey conducted by Franklin Research Institute for CPSC showed that homes built before 1972, and wired with aluminum, are 55 times more likely to have one or more wire connections at outlets reach "Fire Hazard Conditions" than homes wired with copper.}} The safety issues have since been solved by use of larger sizes of aluminium wire (#8AWG and up), and properly designed aluminium wiring is still being installed in place of copper. For example, the Airbus A380 uses aluminum wire in place of copper wire for electrical power transmission.{{cite news |url=https://spectrum.ieee.org/manufacturing-mayday |title=Manufacturing Mayday: Production glitches send Airbus into a tailspin |work=IEEE Spectrum |author=Hellemans, Alexander |date=1 January 2007 |access-date=19 June 2014}}

File:Busbars.jpgs distributing power to a large building]]

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.{{cite web|title=Accelerator: Waveguides (SLAC VVC)|url=http://www2.slac.stanford.edu/vvc/accelerators/waveguide.html|work=SLAC Virtual Visitor Center|access-date=29 April 2011|archive-date=7 February 2006|archive-url=https://web.archive.org/web/20060207181019/http://www2.slac.stanford.edu/vvc/accelerators/waveguide.html|url-status=dead}}

Copper's superior conductivity enhances the efficiency of electrical motors.IE3 energy-saving motors, Engineer Live, http://www.engineerlive.com/Design-Engineer/Motors_and_Drives/IE3_energy-saving_motors/22687/ 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.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 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,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; {{cite web|url=http://www.copper.org/applications/electrical/motor-rotor |title=Copper.org: Copper Motor Rotor Project |access-date=2012-11-07 |url-status=dead |archive-url=https://web.archive.org/web/20120313102458/http://www.copper.org/applications/electrical/motor-rotor |archive-date=13 March 2012 }} are enabling general-purpose induction motors to meet and exceed National Electrical Manufacturers Association (NEMA) premium efficiency standards.NEMA Premium Motors, The Association of Electrical Equipment and Medical Imaging Manufacturers; {{cite web|url=http://www.nema.org/gov/energy/efficiency/premium/ |title=NEMA – NEMA Premium Motors |access-date=2009-10-12 |url-status=dead |archive-url=https://web.archive.org/web/20100402081307/http://www.nema.org/gov/energy/efficiency/premium/ |archive-date=2 April 2010}}

{{Excerpt|Copper in renewable energy}}

{{Main|Copper in architecture}}

File:Minneapolis City Hall.jpg, coated with patina]]

File:Copper utensils Jerusalem.jpg

File:Large copper bowl. Dhankar Gompa.jpg.]]

Copper has been used since ancient times as a durable, corrosion resistant, and weatherproof architectural material.Seale, Wayne (2007). The role of copper, brass, and bronze in architecture and design; Metal Architecture, May 2007Copper roofing in detail; Copper in Architecture; Copper Development Association, U.K., www.cda.org.uk/archArchitecture, European Copper Institute; http://eurocopper.org/copper/copper-architecture.html {{Webarchive|url=https://web.archive.org/web/20121009005711/http://eurocopper.org/copper/copper-architecture.html |date=9 October 2012 }}Kronborg completed; Agency for Palaces and Cultural Properties, København, {{cite web|url=http://www.slke.dk/en/slotteoghaver/slotte/kronborg/kronborgshistorie/kronborgfaerdigbygget.aspx?highlight%3Dcopper |title=Kronborg completed – Agency for Palaces and Cultural Properties |access-date=2012-09-12 |url-status=dead |archive-url=https://web.archive.org/web/20121024101854/http://www.slke.dk/en/slotteoghaver/slotte/kronborg/kronborgshistorie/kronborgfaerdigbygget.aspx?highlight=copper |archive-date=24 October 2012}} 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.{{cn|date=May 2025}}

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.{{cite web|last = Berg|first = Jan|title = Why did we paint the library's roof?|url = http://www.deforest.lib.wi.us/FAQS.htm|access-date = 20 September 2007 |archive-url = https://web.archive.org/web/20070625065039/http://www.deforest.lib.wi.us/FAQS.htm |archive-date = 25 June 2007}}Architectural considerations; Copper in Architecture Design Handbook, http://www.copper.org/applications/architecture/arch_dhb/fundamentals/arch_considerations.htm{{Dead link|date=October 2022 |bot=InternetArchiveBot |fix-attempted=yes }}Peters, Larry E. (2004). Preventing corrosion on copper roofing systems; Professional Roofing, October 2004, http://www.professionalroofing.net It can be a mixture of carbonate and sulfate compounds in various amounts, depending upon environmental conditions such as sulfur-containing acid rain.{{cite web|url=http://www.wepanknowledgecenter.org/c/document_library/get_file?folderId%3D517%26name%3DDLFE-2454.pdf |title=Oxidation reaction: Why is the Statue of Liberty blue-green? How does rust work?|first=Chun|last=Wu|publisher=Engage Engineering|website=wepanknowledgecenter.org |access-date=2013-10-25 |url-status=dead |archive-url=https://web.archive.org/web/20131025094519/http://www.wepanknowledgecenter.org/c/document_library/get_file?folderId=517&name=DLFE-2454.pdf |archive-date=25 October 2013}}{{cite journal |doi=10.1016/S0010-938X(98)00093-6 |title=The chemistry of copper patination |date=1998 |last1=Fitzgerald |first1=K.P. |last2=Nairn |first2=J. |last3=Atrens |first3=A. |journal=Corrosion Science |volume=40 |issue=12 |pages=2029–50|bibcode=1998Corro..40.2029F }}Application Areas: Architecture – Finishes – patina; http://www.copper.org/applications/architecture/finishes.htmlGlossary of copper terms, Copper Development Association (UK): {{cite web|url=http://www.copperinfo.co.uk/resources/glossary.shtml |title=Glossary of copper terms |access-date=2012-09-14 |url-status=dead |archive-url=https://web.archive.org/web/20120820053020/http://www.copperinfo.co.uk/resources/glossary.shtml |archive-date=20 August 2012 }} 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.Finishes – natural weathering; Copper in Architecture Design Handbook, Copper Development Association Inc., {{cite web|url=http://www.copper.org/applications/architecture/arch_dhb/finishes/finishes.html |title=Copper.org: Architecture Design Handbook: Finishes |access-date=2012-09-12 |url-status=dead |archive-url=https://web.archive.org/web/20121016080539/http://www.copper.org/applications/architecture/arch_dhb/finishes/finishes.html |archive-date=16 October 2012 }}

Copper has excellent brazing and soldering properties and can be welded; the best results are obtained with gas metal arc welding.{{cite book|author = Davis, Joseph R. |title = Copper and Copper Alloys|pages = 3–6, 266|publisher = ASM International|date = 2001|isbn = 978-0-87170-726-0}}

{{Main|Copper alloys in aquaculture|Copper sheathing}}

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 conditionsEdding, 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. and have strong structural and corrosion-resistant properties in marine environments.[http://www.copper.org/applications/cuni/pdf/marine_aquaculture.pdf Corrosion Behaviour of Copper Alloys used in Marine Aquaculture] {{Webarchive|url=https://web.archive.org/web/20130924070759/http://www.copper.org/applications/cuni/pdf/marine_aquaculture.pdf |date=24 September 2013 }}. (PDF) . copper.org. Retrieved on 8 November 2011.

{{Main|Antimicrobial properties of copper|Antimicrobial copper-alloy touch surfaces}}

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, SARS-CoV-2, and fungi).[http://coppertouchsurfaces.org/antimicrobial/bacteria/index.html Copper Touch Surfaces] {{webarchive|url=https://web.archive.org/web/20120723235812/http://www.coppertouchsurfaces.org/antimicrobial/bacteria/index.html |date=23 July 2012 }}. Copper Touch Surfaces. Retrieved on 8 November 2011.{{Cite web|date=10 February 2021|title=EPA Registers Copper Surfaces for Residual Use Against Coronavirus|url=https://www.epa.gov/newsreleases/epa-registers-copper-surfaces-residual-use-against-coronavirus|access-date=11 October 2021|website=United States Environmental Protection Agency}} Indians have been using copper vessels since ancient times for storing water, even before modern science realized its antimicrobial properties.{{Cite journal|last1=Montero|first1=David A.|last2=Arellano|first2=Carolina|last3=Pardo|first3=Mirka|last4=Vera|first4=Rosa|last5=Gálvez|first5=Ricardo|last6=Cifuentes|first6=Marcela|last7=Berasain|first7=María A.|last8=Gómez|first8=Marisol|last9=Ramírez|first9=Claudio|last10=Vidal|first10=Roberto M.|date=2019-01-05|title=Antimicrobial properties of a novel copper-based composite coating with potential for use in healthcare facilities|journal=Antimicrobial Resistance and Infection Control|volume=8|issue=1|pages=3|doi=10.1186/s13756-018-0456-4|issn=2047-2994|pmc=6321648|pmid=30627427 |doi-access=free }} Some copper alloys were proven to kill more than 99.9% of disease-causing bacteria within just two hours when cleaned regularly.{{Cite web|date=May 2008|title=EPA registers copper-containing alloy products|url=http://www.epa.gov/pesticides/factsheets/copper-alloy-products.htm|url-status=dead|archive-url=https://web.archive.org/web/20150929135757/http://www.epa.gov/pesticides/factsheets/copper-alloy-products.htm|archive-date=29 September 2015|website=United States Environmental Protection Agency}} 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. Copper doorknobs are used by hospitals to reduce the transfer of disease, and Legionnaires' disease is suppressed by copper tubing in plumbing systems.{{cite journal|last1=Biurrun|first1=Amaya|last2=Caballero|first2=Luis|last3=Pelaz|first3=Carmen|last4=León|first4=Elena|last5=Gago|first5=Alberto|s2cid=32388649|title=Treatment of a Legionella pneumophila-Colonized Water Distribution System Using Copper-Silver Ionization and Continuous Chlorination|journal=Infection Control and Hospital Epidemiology|date=1999|volume=20|issue=6|pages=426–428|doi=10.1086/501645|jstor=30141645|pmid=10395146|url=http://pdfs.semanticscholar.org/0709/96484f04d87e7c7858448f3d913a94b720c0.pdf|archive-url=https://web.archive.org/web/20190217195047/http://pdfs.semanticscholar.org/0709/96484f04d87e7c7858448f3d913a94b720c0.pdf|url-status=dead|archive-date=2019-02-17}} Antimicrobial copper alloy products are now being installed in healthcare facilities in the U.K., Ireland, Japan, Korea, France, Denmark, and Brazil, as well as being called for in the US,Zaleski, Andrew, [https://www.statnews.com/2020/09/24/as-hospitals-look-to-prevent-infections-a-chorus-of-researchers-make-a-case-for-copper-surfaces/ As hospitals look to prevent infections, a chorus of researchers make a case for copper surfaces], STAT, 24 September 2020 and in the subway transit system in Santiago, Chile, where copper–zinc alloy handrails were installed in some 30 stations between 2011 and 2014.[http://www.rail.co/2011/07/22/chilean-subway-protected-with-antimicrobial-copper Chilean subway protected with Antimicrobial Copper – Rail News from] {{webarchive|url=https://web.archive.org/web/20120724105812/http://www.rail.co/2011/07/22/chilean-subway-protected-with-antimicrobial-copper/ |date=24 July 2012 }}. rail.co. Retrieved on 8 November 2011.[http://construpages.com.ve/nl/noticia_nl.php?id_noticia=3032&language=en Codelco to provide antimicrobial copper for new metro lines (Chile)] {{dead link|date=September 2016|bot=medic}}{{cbignore|bot=medic}}. Construpages.com.ve. Retrieved on 8 November 2011.[http://www.antimicrobialcopper.com/media/149689/pr811-chilean-subway-installs-antimicrobial-copper.pdf PR 811 Chilean Subway Installs Antimicrobial Copper] {{webarchive|url=https://web.archive.org/web/20111123100624/http://www.antimicrobialcopper.com/media/149689/pr811-chilean-subway-installs-antimicrobial-copper.pdf |date=23 November 2011 }}. (PDF). antimicrobialcopper.com. Retrieved on 8 November 2011.

Textile fibers can be blended with copper to create antimicrobial protective fabrics.{{cite web |title= Copper and Cupron |publisher=Cupron |url=http://www.cupron.com/cupron-technology/power-of-cupron/copper-and-cupron}}{{unreliable source?|date=November 2013}}

Copper is commonly used in jewelry, and according to some folklore, copper bracelets relieve arthritis symptoms.{{cite journal |pmid=961545 |date=1976 |last1=Walker |first1=W.R. |last2=Keats |first2=D.M. |title=An investigation of the therapeutic value of the 'copper bracelet'-dermal assimilation of copper in arthritic/rheumatoid conditions |volume=6 |issue=4 |pages=454–459 |journal=Agents and Actions}} In one trial for osteoarthritis and one trial for rheumatoid arthritis, no differences were found between copper bracelet and control (non-copper) bracelet.{{cite journal |vauthors=Richmond SJ, Gunadasa S, Bland M, Macpherson H |title=Copper bracelets and magnetic wrist straps for rheumatoid arthritis – analgesic and anti-inflammatory effects: a randomised double-blind placebo controlled crossover trial |journal=PLOS ONE |volume=8 |issue=9 |pages=e71529 |year=2013 |pmid=24066023 |pmc=3774818 |doi=10.1371/journal.pone.0071529 |bibcode=2013PLoSO...871529R |doi-access=free }}{{cite journal|last1=Richmond|first1=Stewart J.|last2=Brown|first2=Sally R.|last3=Campion|first3=Peter D.|last4=Porter|first4=Amanda J.L.|last5=Moffett|first5=Jennifer A. Klaber|last6=Jackson|first6=David A.|last7=Featherstone|first7=Valerie A.|last8=Taylor|first8=Andrew J.|title=Therapeutic effects of magnetic and copper bracelets in osteoarthritis: A randomised placebo-controlled crossover trial|journal=Complementary Therapies in Medicine|volume=17|issue=5–6|year=2009|pages=249–256|issn=0965-2299|doi=10.1016/j.ctim.2009.07.002|pmid=19942103|url=http://researchrepository.napier.ac.uk/id/eprint/9912}} No evidence shows that copper can be absorbed through the skin. If it were, it might lead to copper poisoning.{{cite web |url=http://www.uams.edu/update/absolutenm/templates/medical.asp?articleid=3454|title=Find the Truth Behind Medical Myths|publisher=University of Arkansas for Medical Sciences|date=6 January 2014|archive-date=6 January 2014|

archiveurl=https://web.archive.org/web/20140106233901/http://www.uams.edu/update/absolutenm/templates/medical.asp?articleid=3454|quote=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.}}

Chromobacterium violaceum and Pseudomonas fluorescens can both mobilize solid copper as a cyanide compound.{{cite journal|title=Metals, minerals and microbes: geomicrobiology and bioremediation|journal=Microbiology|author1-link=Geoffrey Michael Gadd|author=Geoffrey Michael Gadd|volume=156|issue=3|date=March 2010|pages=609–643|doi=10.1099/mic.0.037143-0|pmid=20019082|doi-access=free}} 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.{{cite book|url=https://books.google.com/books?id=WY3YvfNoouMC&pg=PA533|title=Mycoremediation: Fungal Bioremediation|author=Harbhajan Singh|page=509|isbn=978-0-470-05058-3|date=2006|publisher=John Wiley & Sons }}

{{Main|Copper in biology}}

File:ARS copper rich foods.jpg

Copper proteins have diverse roles in biological electron transport and oxygen transportation, processes that exploit the easy interconversion of Cu(I) and Cu(II).{{cite book

|first1=Katherine E. |last1=Vest|first2=Hayaa F.|last2=Hashemi|first3=Paul A.|last3=Cobine

|chapter=The Copper Metallome in Eukaryotic Cells |editor1-first=Lucia |editor1-last=Banci |series=Metal Ions in Life Sciences |volume=12

|title=Metallomics and the Cell |date=2013 |pages=451–78|publisher=Springer |isbn=978-94-007-5560-4|doi=10.1007/978-94-007-5561-1_13|pmid=23595680}} electronic-book {{ISBN|978-94-007-5561-1}} {{ISSN|1559-0836}} electronic-{{ISSN|1868-0402}}

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 which stores energy in ATP. The copper atoms are alternatively reduced and oxidized during the electron transfer to oxygen.{{Cite book |title=Cell structure & function: an integrated approach |date=1991 |publisher=Saunders College Pub |isbn=978-0-03-047439-2 |editor-last=Loewy |editor-first=Ariel G. |edition=3 |location=Philadelphia |editor-last2=Siekevitz |editor-first2=Philip}}{{rp|383}} 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).{{cite web|title = Fun facts|work = Horseshoe crab|publisher = University of Delaware|url = http://www.ocean.udel.edu/horseshoecrab/funFacts.html|access-date = 13 July 2008|archive-url = https://web.archive.org/web/20081022053340/http://www.ocean.udel.edu/horseshoecrab/funFacts.html|archive-date = 22 October 2008|url-status = dead}} 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.S.J. Lippard, J.M. Berg "Principles of bioinorganic chemistry" University Science Books: Mill Valley, CA; 1994. {{ISBN|0-935702-73-3}}. The biological role for copper commenced with the appearance of oxygen in Earth's atmosphere.{{cite journal|pmid=10821735|author=Decker, H.|author2=Terwilliger, N.|name-list-style=amp |title=COPs and Robbers: Putative evolution of copper oxygen-binding proteins|journal= Journal of Experimental Biology |volume=203|pages=1777–1782 |date=2000|issue=Pt 12|doi=10.1242/jeb.203.12.1777|doi-access=free|bibcode=2000JExpB.203.1777D }} 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.

File:Thylakoid membrane.png. A central link in this chain is plastocyanin, a blue copper protein.]]

A unique tetranuclear copper center has been found in nitrous-oxide reductase.

{{cite book

|first1=Lisa K.

|last1= Schneider

|first2=Anja

|last2= Wüst

|first3=Anja

|last3= Pomowski

|first4=Lin

|last4= Zhang

|first5=Oliver

|last5= Einsle

|chapter= No Laughing Matter: The Unmaking of the Greenhouse Gas Dinitrogen Monoxide by Nitrous Oxide Reductase

|editor=Peter M.H. Kroneck

|editor2=Martha E. Sosa Torres

|title=The Metal-Driven Biogeochemistry of Gaseous Compounds in the Environment

|series=Metal Ions in Life Sciences

|volume=14

|date=2014

|publisher=Springer

|pages=177–210

|doi=10.1007/978-94-017-9269-1_8

|pmid= 25416395

|isbn= 978-94-017-9268-4

}}

Chemical compounds which were developed for treatment of Wilson's disease have been investigated for use in cancer therapy.{{cite book|last1=Denoyer|first1=Delphine| last2=Clatworthy |first2=Sharnel A.S.| last3=Cater |first3=Michael A. |editor1-last=Sigel|editor1-first=Astrid|editor2-last=Sigel|editor2-first=Helmut|editor3-last=Freisinger|editor3-first=Eva|editor4-last=Sigel|editor4-first=Roland K.O.

|title=Metallo-Drugs: Development and Action of Anticancer Agents|date=2018|volume= 18|doi= 10.1515/9783110470734-016

|pmid=29394035|publisher=de Gruyter GmbH|location=Berlin|chapter= Chapter 16. Copper Complexes in Cancer Therapy|journal=Metal Ions in Life Sciences |pages= 469–506|isbn=978-3-11-047073-4}}

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.{{cite web|url = http://www.copper.org/consumers/health/papers/cu_health_uk/cu_health_uk.html|title = Amount of copper in the normal human body, and other nutritional copper facts|access-date = 3 April 2009|archive-date = 10 April 2009|archive-url = https://web.archive.org/web/20090410055140/http://www.copper.org/consumers/health/papers/cu_health_uk/cu_health_uk.html|url-status = dead}}

Copper is absorbed in the gut, then transported to the liver bound to albumin.{{cite journal|last1=Adelstein|first1=S. J.|last2=Vallee|first2=B. L.|title=Copper metabolism in man|journal=New England Journal of Medicine|date=1961|volume=265|pages=892–897|doi=10.1056/NEJM196111022651806|pmid=13859394|issue=18}} 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.{{cite journal | url = http://www.ajcn.org/content/67/5/965S.abstract | title = Copper transport | pmid = 9587137 | date = 1 May 1998 | author1 = M.C. Linder | journal = The American Journal of Clinical Nutrition | volume = 67 | issue = 5 | pages = 965S–971S | last2 = Wooten | first2 = L. | last3 = Cerveza | first3 = P. | last4 = Cotton | first4 = S. | last5 = Shulze | first5 = R. | last6 = Lomeli | first6 = N.| doi = 10.1093/ajcn/67.5.965S | doi-access = free }} 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.{{cite book | jstor =20170553 | pmid = 775938 | date =1976 | last1 =Frieden | first1 =E. | last2 =Hsieh | first2 =H.S. | title =Ceruloplasmin: The copper transport protein with essential oxidase activity | journal = Advances in Enzymology and Related Areas of Molecular Biology | volume =44 | pages =187–236 | doi=10.1002/9780470122891.ch6| series = Advances in Enzymology – and Related Areas of Molecular Biology | isbn = 978-0-470-12289-1}}{{cite journal | pmid =2301561 | title =Copper transport from ceruloplasmin: Characterization of the cellular uptake mechanism | date =1 January 1990 | author1 =S.S. Percival | journal = American Journal of Physiology. Cell Physiology | volume =258 | issue =1 | pages =C140–C146 | last2 =Harris | first2 =E.D. | doi = 10.1152/ajpcell.1990.258.1.c140 }}

The U.S. Institute of Medicine 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. For both sexes, the RDAs for copper are: 340 μg of copper for 1–3 years old, 440 μg of copper for 4–8 years old, 700 μg of copper for 9–13 years old, 890 μg of copper for 14–18 years old and 900 μg of copper for ages 19 years and older. For pregnancy, 1,000 μg. For lactation, 1,300 μg.[http://www.nationalacademies.org/hmd/~/media/Files/Activity%20Files/Nutrition/DRI-Tables/2_%20RDA%20and%20AI%20Values_Vitamin%20and%20Elements.pdf?la=en Dietary Reference Intakes: RDA and AI for Vitamins and Elements] {{Webarchive|url=https://web.archive.org/web/20181113060244/http://www.nationalacademies.org/hmd/~/media/Files/Activity%20Files/Nutrition/DRI-Tables/2_%20RDA%20and%20AI%20Values_Vitamin%20and%20Elements.pdf?la=en |date=13 November 2018 }} Food and Nutrition Board, Institute of Medicine, National Academies Press, 2011. Retrieved 18 April 2018. As for safety, the Institute of Medicine 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.Copper. IN: [https://www.nap.edu/read/10026/chapter/9 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.

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 are defined the same as in the 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.{{cite web |title=Overview on Dietary Reference Values for the EU population as derived by the EFSA Panel on Dietetic Products, Nutrition and Allergies |year=2017 |url=https://www.efsa.europa.eu/sites/default/files/assets/DRV_Summary_tables_jan_17.pdf}} 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.{{citation |title=Tolerable Upper Intake Levels For Vitamins And Minerals |publisher=European Food Safety Authority |year=2006 |url=http://www.efsa.europa.eu/sites/default/files/efsa_rep/blobserver_assets/ndatolerableuil.pdf}}

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|2016|May|27|lc=y|df=US}}, it was revised to 0.9 mg to bring it into agreement with the RDA.{{cite web|url=https://www.gpo.gov/fdsys/pkg/FR-2016-05-27/pdf/2016-11867.pdf |title=Federal Register May 27, 2016 Food Labeling: Revision of the Nutrition and Supplement Facts Labels. FR p. 33982.}}{{cite web | title=Daily Value Reference of the Dietary Supplement Label Database (DSLD) | website=Dietary Supplement Label Database (DSLD) | url=https://www.dsld.nlm.nih.gov/dsld/dailyvalue.jsp | access-date=16 May 2020 | archive-url=https://web.archive.org/web/20200407073956/https://dsld.nlm.nih.gov/dsld/dailyvalue.jsp | archive-date=7 April 2020 | url-status=dead }} A table of the old and new adult daily values is provided at Reference Daily Intake.{{cn|date=May 2025}}

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.{{Cite book |last1=Scheiber |first1=Ivo |chapter-url=https://link.springer.com/10.1007/978-94-007-7500-8_11 |title=Interrelations between Essential Metal Ions and Human Diseases |last2=Dringen |first2=Ralf |last3=Mercer |first3=Julian F. B. |date=2013 |publisher=Springer Netherlands |isbn=978-94-007-7499-5 |editor-last=Sigel |editor-first=Astrid |volume=13 |location=Dordrecht |pages=359–387 |language=en |chapter=Copper: Effects of Deficiency and Overload |journal=Metal Ions in Life Sciences |doi=10.1007/978-94-007-7500-8_11 |pmid=24470097 |editor-last2=Sigel |editor-first2=Helmut |editor-last3=Sigel |editor-first3=Roland K.O.}} Conversely, Wilson's disease is genetic disease that causes an accumulation of copper in body tissues.{{Cite journal |last1=Ala |first1=Aftab |last2=Walker |first2=Ann P. |last3=Ashkan |first3=Keyoumars |last4=Dooley |first4=James S. |last5=Schilsky |first5=Michael L. |date=2007-02-03 |title=Wilson's disease |url=https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(07)60196-2/abstract |journal=The Lancet |language=English |volume=369 |issue=9559 |pages=397–408 |doi=10.1016/S0140-6736(07)60196-2 |issn=0140-6736 |pmid=17276780}}

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.{{cite journal|last1=Bonham |first1= Maxine |last2= O'Connor |first2= Jacqueline M. |last3= Hannigan |first3= Bernadette M. |last4= Strain |first4= J.J.|date=2002|title=The immune system as a physiological indicator of marginal copper status? |journal=British Journal of Nutrition|doi=10.1079/BJN2002558|pmid=12010579|volume=87|issue=5|pages=393–403|doi-access=free}}

{{Main|Copper toxicity}}

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.{{cite journal|last1=Li|first1=Yunbo|last2=Trush|first2=Michael|last3=Yager|first3=James|title=DNA damage caused by reactive oxygen species originating from a copper-dependent oxidation of the 2-hydroxy catechol of estradiol|journal=Carcinogenesis|date=1994|volume=15|issue=7|pages=1421–1427|doi=10.1093/carcin/15.7.1421|pmid=8033320}}{{cite journal|last1=Gordon|first1=Starkebaum|last2=John|first2=M. Harlan|title=Endothelial cell injury due to copper-catalyzed hydrogen peroxide generation from homocysteine|pmc=424498|pmid=3514679|doi=10.1172/JCI112442|volume=77|issue=4|date=April 1986|journal=J. Clin. Invest.|pages=1370–6}} Corresponding amounts of copper salts (30 mg/kg) are toxic in animals.{{cite web|title = Pesticide Information Profile for Copper Sulfate|url = http://pmep.cce.cornell.edu/profiles/extoxnet/carbaryl-dicrotophos/copper-sulfate-ext.html|publisher = Cornell University|access-date=10 July 2008}} A minimum dietary value for healthy growth in rabbits has been reported to be at least 3 ppm in the diet.{{cite journal|author=Hunt, Charles E.|author2=William W. Carlton|name-list-style=amp |pmid=5841854 |date=1965|title=Cardiovascular Lesions Associated with Experimental Copper Deficiency in the Rabbit|journal=Journal of Nutrition |volume=87|pages=385–394|issue=4|doi=10.1093/jn/87.4.385}} 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.{{cite journal|url=http://riunet.upv.es/handle/10251/10503?locale-attribute=en|author=Ayyat M.S.|author2=Marai I.F.M.|author3=Alazab A.M. |date=1995|title=Copper-Protein Nutrition of New Zealand White Rabbits under Egyptian Conditions|journal= World Rabbit Science |volume=3|issue=3 |pages=113–118|doi=10.4995/wrs.1995.249|doi-access=free|hdl=10251/10503|hdl-access=free}}

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.

Elevated copper levels have also been linked to worsening symptoms of Alzheimer's disease.{{cite journal | author = Brewer GJ | title = Copper excess, zinc deficiency, and cognition loss in Alzheimer's disease | journal = BioFactors | volume = 38 | issue = 2 | pages = 107–113 | date = March 2012 | pmid = 22438177 | doi = 10.1002/biof.1005 | s2cid = 16989047 | type = Review| hdl = 2027.42/90519 | hdl-access = free }}{{cite web|title=Copper: Alzheimer's Disease|url=http://examine.com/supplements/Copper#summary9-0|publisher=Examine.com|access-date=21 June 2015}}

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.{{PGCH|0151}} 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.{{PGCH|0150}}

Copper is a constituent of tobacco smoke.OEHHA [https://oehha.ca.gov/chemicals/copper Copper]{{cite journal|last1=Talhout|first1=Reinskje|last2=Schulz|first2=Thomas|last3=Florek|first3=Ewa|last4=Van Benthem|first4=Jan|last5=Wester|first5=Piet|last6=Opperhuizen|first6=Antoon|title=Hazardous Compounds in Tobacco Smoke|journal=International Journal of Environmental Research and Public Health|volume=8|issue=12|year=2011|pages=613–628|issn=1660-4601|doi=10.3390/ijerph8020613|pmid=21556207|pmc=3084482|doi-access=free}} 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.{{cite journal|title=Investigation of Toxic Metals in the Tobacco of Different Iranian Cigarette Brands and Related Health Issues|journal=Iranian Journal of Basic Medical Sciences|volume=15|issue=1|pages=636–644|pmc=3586865|year=2012|last1=Pourkhabbaz|first1=A.|last2=Pourkhabbaz|first2=H.|pmid=23493960}} The health implications are not clear.{{Cite journal | doi=10.1080/15216540500459667| pmid=16393783|title = Metals in cigarette smoke| journal=IUBMB Life| volume=57| issue=12| pages=805–809|year = 2005|last1 = Bernhard|first1 = David| last2=Rossmann| first2=Andrea| last3=Wick| first3=Georg| s2cid=35694266| doi-access=free}}

• Copper in renewable energy
• Copper nanoparticle
• Erosion corrosion of copper water tubes
• Cold water pitting of copper tube
• List of countries by copper production
• Metal theft
• Operation Tremor
• Anaconda Copper
• Antofagasta PLC
• Codelco
• El Boleo mine
• Grasberg mine
• Copper foil

{{Reflist}}

• {{cite book|title=Handbook of Copper Pharmacology and Toxicology|editor=Massaro, Edward J.|publisher=Humana Press|date=2002|isbn=978-0-89603-943-8}}
• {{cite web|title=Copper: Technology & Competitiveness (Summary) Chapter 6: Copper Production Technology|publisher=Office of Technology Assessment|date=2005|url=http://www.princeton.edu/~ota/disk2/1988/8808/880808.PDF}}
• Current Medicinal Chemistry, Volume 12, Number 10, May 2005, pp. 1161–1208(48) Metals, Toxicity and Oxidative Stress
• {{cite book|title=Materials Science and Engineering: an Introduction|url=https://archive.org/details/materialsscience00call_0|url-access=registration|edition=6th|author=William D. Callister|publisher=Wiley, New York|date=2003|isbn=978-0-471-73696-7|at=Table 6.1, p. 137}}
• [http://www.memsnet.org/material/coppercubulk/ Material: Copper (Cu), bulk], MEMS and Nanotechnology Clearinghouse.
• {{cite journal|author=Kim BE|author2= Nevitt T|author3=Thiele DJ|title=Mechanisms for copper acquisition, distribution and regulation|journal=Nat. Chem. Biol.|volume=4|date=2008|pmid=18277979|doi=10.1038/nchembio.72|issue=3|pages=176–85}}

{{Wikiquote}}

{{Commons}}

{{Wiktionary|copper}}

{{Wikisource}}

• [http://www.periodicvideos.com/videos/029.htm Copper] at The Periodic Table of Videos (University of Nottingham)
• [https://www.dcceew.gov.au/environment/protection/npi/substances/fact-sheets/copper-and-compounds Copper and compounds fact sheet] from the National Pollutant Inventory of Australia
• [https://copperalliance.org/ International Copper Association and the Copper Alliance], a business interest group
• [https://www.copper.org/ Copper.org] – official website of the Copper Development Association, a North American industry association with an extensive site of properties and uses of copper
• [https://www.indexmundi.com/commodities/?commodity=copper&months=300 Price history] of LME Copper, according to the IMF

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