Editing Brass

{{short description|Alloy of copper and zinc}}
{{Redirect-distinguish|Arsenical brass|arsenical bronze|arsenical copper}}
{{Other uses}}
{{Use dmy dates|date=January 2021}}
[[File:Planispheric Astrolabe MET DP105325.jpg|thumb|[[Islamic Golden Age]] brass [[astrolabe]]]]
[[File:Brass lectern in the form of an eagle attributed to Aert van Tricht the Elder, Limburg (Netherlands), c. 1500, The Cloisters.jpg|thumb|upright|Brass [[lectern]] with an eagle. Attributed to [[Aert van Tricht]], [[Limburg (Netherlands)]], c. 1500.]]

'''Brass''' is an [[alloy]] of [[copper]] and [[zinc]], in proportions which can be varied to achieve different colours and mechanical, electrical, acoustic and chemical properties,<ref>''Engineering Designer'' 30(3): 6–9, May–July 2004</ref> but copper typically has the larger proportion, generally {{frac|2|3}} copper and {{frac|1|3}} zinc. In use since prehistoric times, it is a [[substitutional alloy]]: atoms of the two constituents may replace each other within the same crystal structure.

Brass is similar to [[bronze]], a copper alloy that contains [[tin]] instead of zinc.<ref>''Machinery Handbook'', New York, [[Industrial Press]], Edition 24, p. 501</ref> Both bronze and brass may include small proportions of a range of other [[Chemical element|elements]] including [[arsenic]], [[lead]], [[phosphorus]], [[aluminium]], [[manganese]] and [[silicon]]. Historically, the distinction between the two alloys has been less consistent and clear,<ref>{{Cite book|title = Bearings and bearing metals|publisher = The Industrial Press|year = 1921|page = [https://archive.org/details/bearingsandbear01unkngoog/page/n40 29]|url = https://archive.org/details/bearingsandbear01unkngoog}}</ref> and increasingly museums use the more general term "[[list of copper alloys|copper alloy]]".<ref>{{cite web|quote = The term copper alloy should be searched for full retrievals on objects made of bronze or brass. This is because bronze and brass have at times been used interchangeably in the old documentation, and copper alloy is the Broad Term of both. In addition, the public may refer to certain collections by their popular name, such as 'The [[Benin Bronzes]]' most of which are actually made of brass.|url = https://www.britishmuseum.org/research/search_the_collection_database/term_details.aspx?scopeType=Terms&scopeId=18864 |publisher = British Museum|title = copper alloy (Scope note)}}</ref>

Brass has long been a popular material for its bright gold-like appearance and is still used for [[drawer pull]]s and [[door handle|doorknobs]]. It has also been widely used to make sculpture and utensils because of its low melting point, high workability (both with hand tools and with modern [[lathe|turning]] and [[milling (machining)|milling]] machines), durability, and [[electrical conductivity|electrical]] and [[thermal conductivity]]. Brasses with higher copper content are softer and more golden in colour; conversely those with less copper and thus more zinc are harder and more silvery in colour.

Brass is still commonly used in applications where corrosion resistance and low [[friction]] are required, such as [[padlock|lock]]s, [[hinge]]s, [[gear]]s, [[Bearing (mechanical)|bearing]]s, [[ammunition]] casings, [[zipper]]s, [[plumbing]], [[hose coupling]]s, [[valve]]s, SCUBA regulators, and [[AC power plugs and sockets|electrical plugs and sockets]]. It is used extensively for [[brass instrument|musical instruments]] such as [[horn (instrument)|horn]]s and [[metallophone|bell]]s. The composition of brass makes it a favorable substitute for copper in [[costume jewelry]] and [[fashion jewellery|fashion jewelry]], as it exhibits greater resistance to corrosion. Brass is not as hard as bronze and so is not suitable for most weapons and tools. Nor is it suitable for marine uses, because the zinc reacts with minerals in salt water, leaving porous copper behind; marine brass, with added tin, avoids this, as does bronze.

Brass is often used in situations in which it is important that [[spark (fire)|spark]]s not be struck, such as in fittings and tools used near flammable or explosive materials.<ref>{{cite web | url=https://www.ccohs.ca/oshanswers/safety_haz/hand_tools/nonsparking.html | title=Hand Tools – Non-sparking tools | website=Canadian Center for Occupational Health and Safety | date=2017-12-01 | access-date=2022-04-30 }}</ref>

==Properties==
[[File:Microstructure of rolled and annealed brass; magnification 400X.jpg|thumb|[[Microstructure]] of rolled and [[Annealing (metallurgy)|annealed]] brass (400× magnification)]]

Brass is more malleable than bronze or zinc. The relatively low [[melting point]] of brass ({{convert|900|to|940|C|disp=semicolon}}, depending on composition) and its flow characteristics make it a relatively easy material to [[Casting (metalworking)|cast]]. By varying the proportions of copper and zinc, the properties of the brass can be changed, allowing hard and soft brasses. The [[density]] of brass is {{convert|8.4|to|8.73|g/cm3|abbr=on}}.<ref>{{cite web |url = http://www.simetric.co.uk/si_metals.htm |title = Mass, Weight, Density or Specific Gravity of Different Metals |access-date = 9 January 2009 |last = Walker |first = Roger |work = Density of Materials |publisher = SImetric.co.uk |location = United Kingdom |quote = brass – casting, 8400–8700... brass – rolled and drawn, 8430–8730}}</ref>

Today, almost 90% of all brass alloys are recycled.<ref>{{cite book |author1=M. F. Ashby |author2=Kara Johnson |title=Materials and design: the art and science of material selection in product design |url=https://archive.org/details/materialsdesigna0000ashb |url-access=registration |access-date=12 May 2011 |year=2002 |publisher=Butterworth-Heinemann |isbn=978-0-7506-5554-5 |page=[https://archive.org/details/materialsdesigna0000ashb/page/223 223]}}</ref> Because brass is not [[Ferromagnetism|ferromagnetic]], ferrous scrap can be separated from it by passing the scrap near a powerful magnet. Brass scrap is melted and recast into [[billet (semi-finished product)|billets]] that are extruded into the desired form and size. The general softness of brass means that it can often be machined without the use of [[cutting fluid]], though there are exceptions to this.<ref name="Camm1949">{{cite book|author=Frederick James Camm|title=Newnes Engineer's Reference Book|url=https://books.google.com/books?id=iXxGAAAAMAAJ|year=1949|publisher=George Newnes|page=594}}</ref>

Aluminium makes brass stronger and more corrosion-resistant. Aluminium also causes a highly beneficial hard layer of [[aluminium oxide]] (Al<sub>2</sub>O<sub>3</sub>) to be formed on the surface that is thin, transparent, and self-healing. Tin has a similar effect and finds its use especially in [[seawater]] applications (naval brasses). Combinations of iron, aluminium, silicon, and manganese make brass [[wear]]- and [[Tear resistance|tear-resistant]].<ref>{{cite web |url=http://www.copperinfo.co.uk/alloys/brass/downloads/117/117-section-6-types-of-brass.pdf |title=Pub 117 The Brasses – Properties & Applications |access-date=9 May 2012 |author=Copper Development Association |url-status=dead |archive-url=https://web.archive.org/web/20121030061920/http://www.copperinfo.co.uk/alloys/brass/downloads/117/117-section-6-types-of-brass.pdf |archive-date=30 October 2012 }}</ref> The addition of as little as 1% iron to a brass alloy will result in an alloy with a noticeable magnetic attraction.<ref>{{Cite web|url=https://www.scrapmetaljunkie.com/2105/is-brass-magnetic-what-is-magnetic-brass|archive-url=https://web.archive.org/web/20200316090220/https://www.scrapmetaljunkie.com/2105/is-brass-magnetic-what-is-magnetic-brass|url-status=usurped|archive-date=16 March 2020|title=Is Brass Magnetic? What Is Magnetic Brass?|date=1 January 2020|website=Scrap Metal Junkie|language=en-US|access-date=19 January 2020}}</ref>

[[File:Diagramme binaire Cu Zn.svg|thumb|upright=1.6|Binary phase diagram]]
Brass will [[corrosion|corrode]] in the presence of moisture, [[chloride]]s, [[acetate]]s, [[ammonia]], and certain acids. This often happens when the copper reacts with sulfur to form a brown and eventually black surface layer of [[copper sulfide]] which, if regularly exposed to slightly acidic water such as urban rainwater, can then oxidize in air to form a [[patina]] of green-blue [[copper carbonate]]. Depending on how the patina layer was formed, it may protect the underlying brass from further damage.<ref>{{cite book|title=Metals in America's Historic Buildings: Uses and Preservation Treatments|url=https://books.google.com/books?id=g7fCMfvnCKAC&pg=PA119|year=1980|publisher=U.S. Department of the Interior, Heritage Conservation and Recreation Service, Technical Preservation Services|page=119}}</ref>

Although copper and zinc have a large difference in [[electrical potential]], the resulting brass alloy does not experience internalized [[galvanic corrosion]] because of the absence of a corrosive environment within the mixture. However, if brass is placed in contact with a more noble metal such as silver or gold in such an environment, the brass will corrode galvanically; conversely, if brass is in contact with a less-noble metal such as zinc or iron, the less noble metal will corrode and the brass will be protected.

==Lead content==
To enhance the machinability of brass, [[lead]] is often added in concentrations of about 2%. Since lead has a lower [[melting point]] than the other constituents of the brass, it tends to migrate towards the [[Grain boundary|grain boundaries]] in the form of globules as it cools from casting. The pattern the globules form on the surface of the brass increases the available lead surface area which, in turn, affects the degree of leaching. In addition, cutting operations can smear the lead globules over the surface. These effects can lead to significant lead leaching from brasses of comparatively low lead content.<ref>{{Cite book|title = Stagnation Time, Composition, pH, and Orthophosphate Effects on Metal Leaching from Brass|publisher = United States Environmental Protection Agency|date = September 1996|location = Washington DC|page = 7|id = EPA/600/R-96/103 |url=https://cfpub.epa.gov/si/si_public_record_report.cfm?Lab=NRMRL&dirEntryId=126033}}</ref>

In October 1999, the California State Attorney General sued 13 key manufacturers and distributors over lead content. In laboratory tests, state researchers found the average brass key, new or old, exceeded the [[California Proposition 65 (1986)|California Proposition 65]] limits by an average factor of 19, assuming handling twice a day.<ref name="ca_ag">[http://ag.ca.gov/newsalerts/print_release.php?id=529 News & Alerts – California Dept. of Justice – Office of the Attorney General]. 12 October 1999. {{Webarchive|url=https://web.archive.org/web/20081026072238/http://ag.ca.gov/newsalerts/print_release.php?id=529 |date=26 October 2008 }},</ref> In April 2001 manufacturers agreed to reduce lead content to 1.5%, or face a requirement to warn consumers about lead content. Keys plated with other metals are not affected by the settlement, and may continue to use brass alloys with a higher percentage of lead content.<ref>[http://ag.ca.gov/newsalerts/print_release.php?id=1077 News & Alerts – California Dept. of Justice – Office of the Attorney General]. 27 April 2001. {{Webarchive|url=https://web.archive.org/web/20081026054734/http://ag.ca.gov/newsalerts/print_release.php?id=1077 |date=2008-10-26 }}</ref><ref>San Francisco Superior Court, ''People v. Ilco Unican Corp., et al.'' (No. 307102) and ''Mateel Environmental Justice Foundation v. Ilco Unican Corp., et al.'' (No. 305765)</ref>

Also in California, lead-free materials must be used for "each component that comes into contact with the wetted surface of pipes and [[Piping and plumbing fittings|pipe fittings, plumbing fittings]] and fixtures". On 1 January 2010, the maximum amount of lead in "lead-free brass" in California was reduced from 4% to 0.25% lead.<ref name="info.sen.ca.gov">[http://info.sen.ca.gov/pub/05-06/bill/asm/ab_1951-2000/ab_1953_cfa_20060818_134053_sen_floor.html AB 1953 Assembly Bill – Bill Analysis] {{webarchive |url=https://web.archive.org/web/20090925185733/http://info.sen.ca.gov/pub/05-06/bill/asm/ab_1951-2000/ab_1953_cfa_20060818_134053_sen_floor.html |date=25 September 2009 }}. Info.sen.ca.gov. Retrieved on 9 December 2011.</ref><ref>[http://www.dtsc.ca.gov/PollutionPrevention/upload/Lead-in-Plumbing-Fact-Sheet.pdf Requirements for Low Lead Plumbing Products in California] {{Webarchive|url=https://web.archive.org/web/20091002205540/http://www.dtsc.ca.gov/PollutionPrevention/upload/Lead-in-Plumbing-Fact-Sheet.pdf |date=2 October 2009 }}, Fact Sheet, Department of Toxic Substances Control, State of California, February 2009</ref>

==Corrosion-resistant brass for harsh environments==

[[File:00 BMA Automation Sampling cock.JPG|thumb|Brass sampling cock with stainless steel handle]] 
Dezincification-resistant ([[Selective leaching#Leaching of zinc|DZR]] or DR) brasses, sometimes referred to as CR ([[corrosion]] resistant) brasses, are used where there is a large corrosion risk and where normal brasses do not meet the requirements. Applications with high water temperatures, [[chloride]]s present or deviating water qualities ([[soft water]]) play a role. DZR-brass is used in water [[boiler]] systems. This brass alloy must be produced with great care, with special attention placed on a balanced composition and proper production temperatures and parameters to avoid long-term failures.<ref>{{Cite web|title=Corrosion-Resistant (DZR or CR) Brass For Harsh Environments|url=https://www.rubinc.com/corrosion-resistant-dzr-or-cr-brass-for-harsh-environments/|date=2016-05-24|website=RuB Inc|access-date=2020-05-26|df=dmy-all}}</ref><ref>{{Cite web|title=Brass|url=https://oceanfootprint.co.uk/product-category/metal-grades/brass/|website=Ocean Footprint|access-date=2020-05-26|df=dmy-all}}</ref>

An example of DZR brass is the C352 brass, with about 30% zinc, 61–63% copper, 1.7–2.8% lead, and 0.02–0.15% arsenic. The lead and arsenic significantly suppress the zinc loss.<ref>{{cite web |url=https://www.metalalloyscorporation.com/pdf/c352-dezincification-resistant-brass.pdf |archive-url=https://ghostarchive.org/archive/20221009/https://www.metalalloyscorporation.com/pdf/c352-dezincification-resistant-brass.pdf |archive-date=2022-10-09 |url-status=live |title=Specifications|website=Metal Alloys Corporation |access-date=2021-01-06}}</ref>

"Red brasses", a family of alloys with high copper proportion and generally less than 15% zinc, are more resistant to zinc loss. One of the metals called "red brass" is 85% copper, 5% tin, 5% lead, and 5% zinc. Copper alloy C23000, which is also known as "red brass", contains 84–86% copper, 0.05% each iron and lead, with the balance being zinc.<ref>{{Cite web|title=Red Brass/Gunmetals|url=https://www.copper.org/applications/marine/other-copper-alloys/brasses/red-brass-gunmetals.html|website=Copper.org|access-date=2020-05-26|df=dmy-all}}</ref>

Another such material is [[gunmetal]], from the family of red brasses. Gunmetal alloys contain roughly 88% copper, 8–10% tin, and 2–4% zinc. Lead can be added for ease of machining or for bearing alloys.<ref>{{Cite web|title=Gunmetal {{!}} metallurgy|url=https://www.britannica.com/technology/gunmetal|website=Encyclopædia Britannica|access-date=2020-05-26|df=dmy-all}}</ref>

"Naval brass", for use in seawater, contains 40% zinc but also 1% tin. The tin addition suppresses zinc-leaching.<ref>{{Cite web|title=What is Naval Brass?|url=https://www.nationalbronze.com/News/what-is-naval-brass/|date=2013-05-17|website=National Bronze Manufacturing|access-date=2020-05-26}}</ref>

The [[NSF International]] requires brasses with more than 15% zinc, used in [[piping and plumbing fitting]]s, to be dezincification-resistant.<ref>{{Cite web|url=https://www.thoughtco.com/composition-of-common-brass-alloys-2340109|title=Here's Why Alloys Can Change the Properties of Brass|last1=Bell |first1=Terence |website=ThoughtCo |access-date=28 January 2021}}</ref>

==Use in musical instruments==
{{one source|section|date=January 2021}}
[[File:Trumpets02262006.jpg|thumb|left|upright|A collection of brass instruments]]
The high [[Ductility|malleability]] and workability, relatively good resistance to [[corrosion]], and traditionally attributed [[acoustics|acoustic]] properties of brass, have made it the usual metal of choice for construction of [[musical instrument]]s whose acoustic [[resonator]]s consist of long, relatively narrow tubing, often folded or coiled for compactness; [[silver]] and its alloys, and even [[gold]], have been used for the same reasons, but brass is the most economical choice. Collectively known as [[brass instrument]]s, or simply 'the brass', these include the [[trombone]], [[tuba]], [[trumpet]], [[cornet]], [[flugelhorn]], [[baritone horn]], [[euphonium]], [[tenor horn]], and [[French horn]], and many other "[[Horn (instrument)|horn]]s", many in variously sized families, such as the [[saxhorns]].

Other [[wind instrument]]s may be constructed of brass or other metals, and indeed most modern student-model [[flute]]s and [[piccolo]]s are made of some variety of brass, usually a [[cupronickel]] [[alloy]] similar to [[nickel silver|nickel silver (also known as German silver)]]. [[Clarinets]], especially low clarinets such as the [[Contrabass clarinet|contrabass]] and [[Subcontrabass clarinet|subcontrabass]], are sometimes made of metal because of limited supplies of the dense, fine-grained tropical hardwoods traditionally preferred for smaller [[woodwind]]s. For the same reason, some low clarinets, [[bassoon]]s and [[contrabassoon]]s feature a hybrid construction, with long, straight sections of wood, and curved joints, neck, and/or bell of metal. The use of metal also avoids the risks of exposing wooden instruments to changes in temperature or humidity, which can cause sudden cracking. Even though the [[saxophone]]s and [[sarrusophone]]s are classified as woodwind instruments, they are normally made of brass for similar reasons, and because their wide, conical bores and thin-walled bodies are more easily and efficiently made by forming sheet metal than by machining wood.

The keywork of most modern woodwinds, including wooden-bodied instruments, is also usually made of an alloy such as nickel silver. Such alloys are stiffer and more durable than the brass used to construct the instrument bodies, but still workable with simple hand tools—a boon to quick repairs. The [[Mouthpiece (brass)|mouthpiece]]s of both brass instruments and, less commonly, woodwind instruments are often made of brass among other metals as well.

Next to the brass instruments, the most notable use of brass in music is in various [[percussion instrument]]s, most notably [[cymbal]]s, [[gong]]s, and [[Tubular bells|orchestral (tubular) bells]] (large "church" [[bell]]s are normally made of [[bronze]]). Small [[handbell]]s and "[[jingle bell]]s" are also commonly made of brass.

The [[harmonica]] is a [[free reed aerophone]], also often made from brass. In [[Reed pipe|organ pipes]] of the reed family, brass strips (called tongues) are used as the reeds, which beat against the [[reed pipe|shallot]] (or beat "through" the shallot in the case of a "free" reed). Although not part of the brass section, [[snare drum]]s are also sometimes made of brass. Some parts on [[electric guitars]] are also made from brass, especially inertia blocks on tremolo systems for its tonal properties, and for string nuts and saddles for both tonal properties and its low friction.<ref>{{Cite web|title=Copper in the Arts Magazine – August 2007: The Art of Brass Instruments|url=https://www.copper.org/consumers/arts/2007/august/Art_History_Brass_Musical_Instruments.html|website=Copper.org|access-date=2020-05-26|df=dmy-all}}</ref>

==Germicidal and antimicrobial applications==
{{Main|Antimicrobial copper-alloy touch surfaces}}
{{See also|Antimicrobial properties of copper|Copper alloys in aquaculture}}

The [[bactericidal]] properties of brass have been observed for centuries, particularly in marine environments where it prevents [[biofouling]]. Depending upon the type and concentration of [[pathogen]]s and the medium they are in, brass kills these [[microorganism]]s within a few minutes to hours of contact.<ref name="autogenerated1"/><ref name=r6/><ref name=r7/>

A large number of independent studies<ref name="autogenerated1"/><ref name=r6/><ref name=r7/><ref name=r1/><ref name=r10/><ref name=r20/><ref name=r25/> confirm this antimicrobial effect, even against antibiotic-resistant bacteria such as MRSA and VRSA. The mechanisms of antimicrobial action by copper and its alloys, including brass, are a subject of intense and ongoing investigation.<ref name=r6/><ref name=r8/><ref name=r9/>

==Season cracking==
[[File:BrassSCC1.jpg|thumb|Cracking in brass caused by [[ammonia]] attack]]
Brass is susceptible to [[stress corrosion cracking]],<ref>{{Cite book|url=https://books.google.com/books?id=yQKuSOzkLvcC&q=brass+susceptible+to+stress+corrosion+cracking&pg=PA31|title=Copper and Bronze in Art: Corrosion, Colorants, Conservation|last=Scott|first=David A.|date=2002|publisher=Getty Publications|isbn=9780892366385|language=en}}</ref> especially from [[ammonia]] or substances containing or releasing ammonia. The problem is sometimes known as [[season cracking]] after it was first discovered in brass [[Cartridge (firearms)|cartridge]]s used for [[rifle]] [[ammunition]] during the 1920s in the [[British Indian Army]]. The problem was caused by high [[residual stress]]es from cold forming of the cases during manufacture, together with chemical attack from traces of ammonia in the atmosphere. The cartridges were stored in stables and the ammonia concentration rose during the hot summer months, thus initiating brittle cracks. The problem was resolved by [[Annealing (metallurgy)|annealing]] the cases, and storing the cartridges elsewhere.

==Types==

{|class="wikitable"
! rowspan=2 | Class
! colspan=2 | Proportion by weight (%)
! rowspan=2 class="unsortable"| Notes
|-
! Copper
! Zinc
|-
| Alpha brasses || >&nbsp;65 || <&nbsp;35 || Alpha brasses are malleable, can be worked cold, and are used in pressing, forging, or similar applications. They contain only one phase, with [[face-centred cubic]] [[crystal structure]]. With their high proportion of copper, these brasses have a more golden hue than others. The alpha phase is a substitution [[solid solution]] of zinc in copper. It is close in properties to copper, tough, strong, and somewhat difficult to machine. Best formability is with 32% of zinc. Corrosion-resistant red brasses, with 15% of zinc or less, belong here.
|-
| Alpha-beta brasses || 55–65 || 35–45 || Also called ''duplex brasses'', these are suited for hot working. They contain both α and β' phases; the β'-phase is ordered [[body-centred cubic]], with zinc atoms in the centre of the cubes, and is harder and stronger than α. Alpha-beta brasses are usually worked hot. The higher proportion of zinc means these brasses are brighter than alpha brasses. At 45% of zinc the alloy has the highest strength.
|-
| Beta brasses{{citation needed|reason=example needed – none here or under "copper alloys"|date=January 2015}} || 50–55 || 45–50 || Beta brasses can only be worked hot, and are harder, stronger, and suitable for casting. The high zinc-low copper content means these are some of the brightest and least-golden of the common brasses.
|-
| Gamma brasses || 33–39 || 61–67 || There are also Ag-Zn and Au-Zn gamma brasses, Ag 30–50%, Au 41%.<ref>{{cite journal |last1=Bradley |first1=A. J. |last2=Thewlis |first2=J. |date=1 October 1926 |title=The Structure of γ-Brass |journal=Proceedings of the Royal Society |bibcode=1926RSPSA.112..678B |doi-access= |doi=10.1098/rspa.1926.0134 |volume=112 |issue=762 |pages=678–692}}</ref> The gamma phase is a cubic-lattice [[intermetallic compound]], Cu<sub>5</sub>Zn<sub>8</sub>.
|-
| White brass || <&nbsp;50 || >&nbsp;50 || These are too brittle for general use. The term may also refer to certain types of [[nickel silver]] alloys as well as Cu-Zn-Sn alloys with high proportions (typically 40%+) of tin and/or zinc, as well as predominantly zinc casting alloys with copper additives. These have virtually no yellow colouring at all, and instead have a much more silvery appearance.
|}

Other phases than α, β and γ are ε, a hexagonal intermetallic CuZn<sub>3</sub>, and η, a solid solution of copper in zinc.

===Brass alloys===
{|class="wikitable sortable"
! rowspan=2 | Alloy name
! colspan=4 | Proportion by weight (%)
! rowspan=2 class="unsortable" | Other
! rowspan=2 class="unsortable" | Notes
|-
! Copper
! Zinc
! Tin
! Lead
|-
| Abyssinian gold (Commercial bronze [C220]) || 90 || 10 || || || ||
|-
| Admiralty brass || 69 || 30 || 1 || || || Tin inhibits [[dezincification resistant brass|loss of zinc]] in many environments. 
|-
| Aich's alloy || 60.66 || 36.58 || 1.02 || || 1.74% iron || Designed for use in marine service owing to its corrosion resistance, hardness and toughness. A characteristic application is to the protection of ships' bottoms, but more modern methods of cathodic protection have rendered its use less common. Its appearance resembles that of gold.<ref>Simons, E. N. (1970). ''A Dictionary of Alloys'', [[Cornell University]]</ref>
|-
| Aluminium brass ||77.5 ||20.5 || || || 2% aluminium || Aluminium improves corrosion resistance. It is used for heat exchanger and condenser tubes.<ref name="Davis2001">{{cite book|author=Joseph R. Davis|title=Copper and Copper Alloys|url=https://books.google.com/books?id=sxkPJzmkhnUC&pg=PA249|date=1 January 2001|publisher=ASM International|isbn=978-0-87170-726-0|page=7}}</ref>
|-
| Arsenical brass || || || || || style="white-space:nowrap" | [[Arsenic]]; frequently [[aluminium]] || Used for boiler [[Firebox (steam engine)|fireboxes]].<ref>{{cite web |url= https://www.matweb.com/search/datasheet.aspx?matguid=9e9610ea79184323840d8838c6591e8b |title= Aluminum Brass Arsenical, UNS C68700 |work= [[MatWeb]] |access-date= 18 October 2023}}</ref><ref name=awm>{{cite web |url= https://www.australwright.com.au/technical-data/alloys/copper-brass/c26130-70-30-arsinical-brass/ |title= 70/30 Arsinical Brass Alloy 259, UNS-C26130 |work= Austral Wright Metals |date= 2021 |access-date= 18 October 2023 |archive-url= https://web.archive.org/web/20230608211306/https://www.australwright.com.au/technical-data/alloys/copper-brass/c26130-70-30-arsinical-brass/ |archive-date= 8 June 2023 |url-status= live}}</ref>
|-
| Arsenical brass 259 || 70 || 29.5 || || ≤0.05 || Arsenic 0.2-0.6, Iron ≤0.05 || Heat exchangers, plumbing requiring excellent corrosion resistance in water.<ref name=awm/>
|-
| Brastil || - || - || - || - || Copper, Silicon, Zinc  || An alloy of copper, zinc, and silicon which has an incredibly high tensile strength and is corrosion resistant. Doehler Die Casting Co. of Toledo, Ohio were known for the production of Brastil.<ref>{{cite web | url=https://www.utoledo.edu/library/canaday/HTML_findingaids/MSS-202.html | title=Doehler-Jarvis Company Collection, MSS-202 }}</ref><ref>Woldman’s Engineering Alloys, 9th Edition 1936, American Society for Metals, {{ISBN|978-0-87170-691-1}}</ref> It was notably tested in 1932 on an [[M1911 pistol]] as it was cheaper than steel at the time as a cost-effective measure.
|-
| California lead-free brass || || || || <&nbsp;0.25 || || Defined by California Assembly Bill AB 1953 contains "not more than 0.25 percent lead content".<ref name="info.sen.ca.gov" /> Prior upper limit was 4%.
|-
| Cartridge brass (C260) || 70 || 30 || &mdash; || ≤{{nbsp}}0.07<ref name="alcobrametals.com">{{Cite web|url=https://alcobrametals.com/brass-product-guide/|title=Brass Product Guide}}</ref> || || Good [[cold work]]ing properties. Used for ammunition cases, plumbing, and hardware. 
|-
| Common brass || 63 || 37 || || || || Also called ''rivet brass''. Cheap and standard for cold working.
|-
| DZR brass || || || || || Arsenic || Dezincification resistant brass with a small percentage of arsenic.
|-
| Delta metal || 55 || 41–43 || || || 1–3% iron with the balance consisting of various other metals. || The proportions used make the material harder and suitable for valves and bearings.
|-
| Free machining brass (C360) || 61.5 || 35.5 || || 2.5–3.7 || 0.35% iron || Also called 360 or C360 brass. High machinability.<ref name="alcobrametals.com"/> 
|-
| [[Gilding metal]] || 95 || 5 || || || || Softest type of brass commonly available. Gilding metal is typically used for ammunition bullet "jackets"; e.g., [[full metal jacket bullet|full metal jacket]] bullets. Almost red in colour.
|-
| [[Gunmetal]] || 88 || 10 || 2 || || || E.g. British Admiralty gunmetal. Has variations.
|-
| High brass || 65 || 35 || || || || Has a high [[tensile strength]] and is used for [[spring (device)|springs]], [[screw]]s, and [[rivet]]s.
|-
| Leaded brass || || || || &gt;&nbsp;0 ||  || An alpha-beta brass with an addition of [[lead]] for improved machinability.
|-
| Low brass || 80 || 20 || || || || Light golden colour, very ductile; used for flexible metal hoses and metal [[bellows]].
|-
| Manganese brass || 77 || 12 || || || 7% [[manganese]], 4% [[nickel]] || Used as cladding for United States [[dollar coin (United States)|golden dollar]] coins.<ref>{{cite web | title=The Presidential Dollars | url=https://www.copper.org/publications/newsletters/innovations/2007/04/presidential_dollars.html | website=Copper Development Association | date=April 2007}}</ref> Other manganese brass alloy compositions exist.
|-
| [[Muntz metal]] || 60 || 40 || || || Traces of iron || Used as a lining on boats.
|-
| Naval brass (C464) || 59 || 40 || 1 || || || Similar to admiralty brass. Also known as Tobin bronze, 464, or C464.<ref name="Kormax" >{{cite web|url=https://kormax.co.nz/products/464-naval-brass/ |title=464 Naval Brass (Tobin Bronze) |publisher=Kormax Engineering Supplies |access-date= 4 December 2017 |archive-url= https://web.archive.org/web/20200817155547/https://kormax.co.nz/products/464-naval-brass/ |archive-date= 17 August 2020}}</ref>{{anchor|Tobin bronze}}
|-
| Naval brass, high lead (C485) || 60.5 || 37.5 || 1.8 || 0.7 || || Naval brass with added lead for machinability. Also known as 485, or C485.<ref>{{cite web |url= https://www.avivametals.com/products/c48500-naval-brass-high-leaded |title= C48500 Naval Brass "High Leaded" |publisher= Aviva Metals |date= 2023 |access-date= 18 October 2023 |archive-url= https://web.archive.org/web/20221128174023/https://www.avivametals.com/products/c48500-naval-brass-high-leaded |archive-date= 28 November 2022 |url-status= live}}</ref>
|-
| [[Nickel brass]] || 70–76 || 20–24.5 || || || 4–5.5% nickel || The outer ring of the bi-metallic [[One pound (British coin)|one pound]] and [[two pounds (British coin)|two pound]] sterling coins and the [[Euro coins#Specification|one euro coin]], plus the centre part of the two euro coin. Formerly used for the round one pound coin.
|-
| [[Nordic gold]] || 89 || 5 || 1 || || 5% aluminum || Used in 10, 20, and 50 cents [[euro coins#Small-denomination coins|euro coins]].
|-
| [[Orichalcum]] || 75-80 || 15-20 || || Trace || Trace amounts of nickel and iron || Determined from 39 ingots recovered from an ancient shipwreck in [[Gela]], [[Sicily]].
|-
| [[Pinchbeck (alloy)|Pinchbeck]] || 89% or 93% || 11% or 7% || || || || Invented in the early 18th century by Christopher Pinchbeck. Resembles gold to a point where people can buy the metal as budget gold "effect" jewelry.
|-
| Prince's metal || 75 || 25 || || || || A type of alpha brass. Due to its yellow colour, it is used as an imitation of gold.<ref>[http://www.npi.gov.au/database/substance-info/profiles/27.html National Pollutant Inventory – Copper and compounds fact sheet] {{webarchive |url=https://web.archive.org/web/20080302034606/http://www.npi.gov.au/database/substance-info/profiles/27.html |date=2 March 2008 }}. Npi.gov.au. Retrieved on 9 December 2011.</ref> Also called ''Prince Rupert's metal'', the alloy was named after [[Prince Rupert of the Rhine]].
|-
| [[ounce metal]] || 85 || 5 || 5 || 5 || || Sometimes called "red brass"
|-
| ''copper alloy C23000'' || 84–85.9 || 14-16 || || minimum 0.07%  || minimum 0.05% iron || <ref name="alcobrametals.com"/><ref name="suppliersonline.com">{{cite web|title=C23000 Copper Alloys (Red Brass, C230) Material Property Data Sheet |url=http://www.suppliersonline.com/propertypages/C23000.asp |access-date=26 August 2010 |archive-url=https://web.archive.org/web/20100330005005/http://www.suppliersonline.com/propertypages/C23000.asp |archive-date=30 March 2010 |url-status=dead }}</ref> Sometimes called "red brass"
|-
| Red brass, Rose brass (C230)|| 85 || 5 || 5 || 5 || || Both an American term for the copper-zinc-tin alloy known as [[gunmetal]], and an alloy which is considered both a brass and a bronze.<ref>{{Cite book|last = Ammen| first = C. W.|title = Metalcasting|publisher = McGraw–Hill Professional|year = 2000|page = [https://archive.org/details/metalcasting00cwam/page/133 133]|isbn = 978-0-07-134246-9|url=https://archive.org/details/metalcasting00cwam|url-access = registration}}</ref><ref name=twsI26>{{cite news
 |author= Jeff Pope
 |title= Plumbing problems may continue to grow
 |newspaper= Las Vegas Sun
 |quote= ... Red brass typically has 5 percent to 10 percent zinc ...
 |date= 23 February 2009
 |url= http://www.lasvegassun.com/news/2009/feb/23/plumbing-problems-may-continue-grow/
 |access-date= 9 July 2011
}}</ref> Red brass is also an alternative name for ''copper alloy C23000'', which is composed of 14–16% zinc, a minimum 0.05% iron and minimum 0.07% lead content,<ref name="alcobrametals.com"/> and the remainder copper.<ref name="suppliersonline.com"/> It may also refer to [[ounce metal]] (Cu 85.0, Zn 5.0, Pb 5.0, Sn 5.0).
|-
| style="white-space:nowrap" | Rich low brass, [[Tombac]] || 80-97 || 5–20 || || || || Often used in jewelry applications. Many variations.
|-
| [[Silicon tombac]] || 80 || 16 || || || 4% silicon || Used as an alternative for investment cast steel parts.
|-
| Tonval brass || || || || &gt;{{nbsp}}0 || || Also called CW617N or CZ122 or OT58. It is not recommended for sea water use, being susceptible to dezincification.<ref>{{Cite book|title = Surveying Yachts and Small Craft|publisher = Adlard Coles|year = 2011|page = 125|quote= Beware of through hull fittings and tailpipes, or any other component in the assembly, made of TONVAL. This is basically brass and totally unsuitable for use below the waterline due to its tendency to dezincify and disintegrate|url = https://books.google.com/books?id=ULky89_6e0QC&pg=PA125|isbn = 9781408114032}}</ref><ref>[http://www.aquafax.co.uk/aquafax_v2/html/images/aceimages/TechData.pdf Print Layout 1] {{webarchive |url=https://web.archive.org/web/20070808150005/http://www.aquafax.co.uk/aquafax_v2/html/images/aceimages/TechData.pdf |date=8 August 2007 }}. (PDF) . Retrieved on 9 December 2011.</ref>
|-
| Yellow brass || 67 || 33 || || || || An American term for 33% zinc brass.
|}

==History==
{{further|Art in bronze and brass}}

Although forms of brass have been in use since [[prehistory]],<ref>Thornton, C. P. (2007) [http://www.safarmer.com/Indo-Eurasian/Brass2007.pdf "Of brass and bronze in prehistoric southwest Asia"] {{Webarchive|url=https://web.archive.org/web/20150924093433/http://www.safarmer.com/Indo-Eurasian/Brass2007.pdf |date=24 September 2015 }} in La Niece, S. Hook, D. and Craddock, P.T. (eds.) ''Metals and mines: Studies in archaeometallurgy'' London: Archetype Publications. {{ISBN|1-904982-19-0}}</ref> its true nature as a copper-zinc alloy was not understood until the post-medieval period because the zinc [[vapor]] which reacted with copper to make brass was not recognized as a [[metal]].<ref>de Ruette, M. (1995) "From Contrefei and Speauter to Zinc: The development of the understanding of the nature of zinc and brass in Post Medieval Europe" in Hook, D. R. and [[David Gaimster|Gaimster, D. R. M]] (eds). ''Trade and Discovery: The Scientific Study of Artefacts from Post Medieval Europe and Beyond''. London: British Museum Occasional Papers 109</ref> The [[King James Bible]] makes many references to "brass"<ref>Cruden's Complete Concordance p. 55</ref> to translate "nechosheth" (bronze or copper) from Hebrew to English. The earliest brasses may have been natural alloys made by [[smelting]] zinc-rich copper [[ore]]s.<ref name=Craddock>Craddock, P. T. and Eckstein, K (2003) "Production of Brass in Antiquity by Direct Reduction" in Craddock, P. T. and Lang, J. (eds.) ''Mining and Metal Production Through the Ages''. London: British Museum, pp. 226–27</ref> By the [[Ancient Rome|Roman]] period brass was being deliberately produced from metallic copper and zinc minerals using the [[Cementation process#Brass production|cementation]] process, the product of which was [[calamine brass]], and variations on this method continued until the mid-19th century.<ref>Rehren and Martinon Torres 2008, pp. 170–175</ref> It was eventually replaced by [[spelter]]ing, the direct alloying of copper and zinc metal which was introduced to [[Europe]] in the 16th century.<ref name=Craddock/>

Brass has sometimes historically been referred to as "yellow copper".<ref>{{Cite book|last=Chen|first=Hailian|url=https://books.google.com/books?id=z2d9DwAAQBAJ&q=%22yellow+copper%22+brass&pg=PA93|title=Zinc for Coin and Brass: Bureaucrats, Merchants, Artisans, and Mining Laborers in Qing China, ca. 1680s–1830s|date=2018-12-03|publisher=BRILL|isbn=978-90-04-38304-3|language=en|df=dmy-all}}</ref><ref>{{Cite book|last=Humphreys|first=Henry Noel|url=https://books.google.com/books?id=OhoLAAAAIAAJ&q=%22yellow+copper%22+brass&pg=PA374|title=The Coin Collector's Manual: Comprising an Historical and Critical Account of the Origin and Progress of Coinage, from the Earliest Period to the Fall of the Roman Empire; with Some Account of the Coinages of Modern Europe, More Especially of Great Brit|date=1897|publisher=Bell|language=en}}</ref>

===Early copper-zinc alloys===
In [[West Asia]] and the [[Eastern Mediterranean]] early copper-zinc alloys are now known in small numbers from a number of 3rd millennium BC sites in the [[Aegean Sea|Aegean]], [[Iraq]], the [[United Arab Emirates]], [[Kalmykia]], [[Turkmenistan]] and [[Georgia (country)|Georgia]] and from 2nd millennium BC sites in [[western India]], [[Uzbekistan]], [[Iran]], [[Syria]], Iraq and [[Canaan]].<ref>Thornton 2007, pp. 189–201</ref> Isolated examples of copper-zinc [[alloy]]s are known in [[China]] from the 1st century AD, long after bronze was widely used.<ref name=r5/> The hilt of [[Sirohi sword|Sirohi swords]] were made up of [[brass]] in [[India]].

The compositions of these early "brass" objects are highly variable and most have zinc contents of between 5% and 15% wt which is lower than in brass produced by cementation.<ref name="Craddock and Eckstein 2003 p.217">Craddock and Eckstein 2003 p. 217</ref> These may be "natural alloys" manufactured by smelting zinc rich copper ores in [[redox]] conditions. Many have similar tin contents to contemporary bronze [[Artifact (archaeology)|artefacts]] and it is possible that some copper-zinc alloys were accidental and perhaps not even distinguished from copper.<ref name="Craddock and Eckstein 2003 p.217"/> However the large number of copper-zinc alloys now known suggests that at least some were deliberately manufactured and many have zinc contents of more than 12% wt which would have resulted in a distinctive golden colour.<ref name="Craddock and Eckstein 2003 p.217" /><ref>Thornton, C. P. and Ehlers, C. B. (2003) "Early Brass in the ancient Near East", in IAMS Newsletter 23 pp. 27–36</ref>

By the 8th–7th century BC [[Assyria]]n [[cuneiform]] tablets mention the exploitation of the "copper of the mountains" and this may refer to "natural" brass.<ref>Bayley 1990, p. 8</ref> "Oreikhalkon" (mountain copper),<ref>{{cite web|url=http://www.oxforddictionaries.com/definition/english/orichalc?q=orichalcum|archive-url=https://web.archive.org/web/20150109114154/http://www.oxforddictionaries.com/definition/english/orichalc?q=orichalcum|url-status=dead|archive-date=9 January 2015|title=orichalc – definition of orichalc in English from the Oxford dictionary|work=oxforddictionaries.com}}</ref> the [[Ancient Greek]] translation of this term, was later adapted to the [[Latin]] ''[[aurichalcum]]'' meaning "golden copper" which became the standard term for brass.<ref>Rehren and Martinon Torres 2008, p. 169</ref> In the 4th century BC [[Plato]] knew ''orichalkos'' as rare and nearly as valuable as gold<ref name=r11/> and [[Pliny the Elder|Pliny]] describes how ''aurichalcum'' had come from [[Cyprus|Cypriot]] ore deposits which had been exhausted by the 1st century AD.<ref>Pliny the Elder ''Historia Naturalis'' XXXIV 2</ref> [[X-ray fluorescence]] analysis of 39 [[orichalcum]] ingots recovered from a 2,600-year-old shipwreck off Sicily found them to be an alloy made with 75–80% copper, 15–20% zinc and small percentages of nickel, lead and iron.<ref>{{cite web|url=http://news.discovery.com/history/archaeology/atlantis-legendary-metal-found-in-shipwreck-150106.htm|title=Atlantis' Legendary Metal Found in Shipwreck|work=DNews|date=2017-05-10|df=dmy-all|access-date=9 January 2015|archive-date=17 May 2016|archive-url=https://web.archive.org/web/20160517080612/http://news.discovery.com/history/archaeology/atlantis-legendary-metal-found-in-shipwreck-150106.htm|url-status=dead}}</ref><ref>{{cite web|url=http://www.archaeology.org/news/2874-150107-sicily-orichalcum-metal|title=Unusual Metal Recovered from Ancient Greek Shipwreck – Archaeology Magazine|author=Jessica E. Saraceni|work=archaeology.org|date=7 January 2015 }}</ref>

===Roman world===
[[File:Iranian - Ewer - Walters 54457 - Profile.jpg|thumb|upright|7th-century Persian [[ewer]] in brass with copper inlay, [[Walters Art Museum]], [[Baltimore]], Maryland, US]]

During the later part of first millennium BC the use of brass spread across a wide geographical area from [[United Kingdom|Britain]]<ref>{{cite journal |last1=Craddock |first1=P. T. |last2=Cowell |first2=M. |last3=Stead |first3=I. |year=2004 |title=Britain's first brass |journal=Antiquaries Journal |doi=10.1017/S000358150004587X |volume=84 |pages=339–46|s2cid=163717910 }}</ref> and [[Spain]]<ref name=r13/> in the west to [[Iran]], and [[India]] in the east.<ref>Craddock and Eckstein 2003, pp. 216–7</ref> This seems to have been encouraged by exports and influence from the [[Middle East]] and eastern Mediterranean where deliberate production of brass from metallic copper and zinc ores had been introduced.<ref>Craddock and Eckstein 2003, p. 217</ref> The 4th century BC writer [[Theopompus]], quoted by [[Strabo]], describes how heating earth from [[Astyra (Aeolis)|Andeira]] in [[Turkey]] produced "droplets of false silver", probably metallic zinc, which could be used to turn copper into oreichalkos.<ref>Bayley 1990, p. 9</ref> In the 1st century BC the Greek [[Dioscorides]] seems to have recognized a link between zinc [[mineral]]s and brass describing how [[Cadmia]] ([[zinc oxide]]) was found on the walls of [[Metallurgical furnace|furnace]]s used to heat either zinc ore or copper and explaining that it can then be used to make brass.<ref>Craddock and Eckstein 2003, pp. 222–224. Bayley 1990, p. 10.</ref>

By the first century BC brass was available in sufficient supply to use as [[coin]]age in [[Phrygia]] and [[Bithynia]],<ref name=r14/> and after the Augustan [[currency reform]] of 23 BC it was also used to make Roman ''[[dupondius|dupondii]]'' and ''[[Sestertius|sestertii]]''.<ref name=r15/> The uniform use of brass for coinage and military equipment across the [[Roman world]] may indicate a degree of state involvement in the industry,<ref>Bayley 1990, p. 21</ref><ref name=r16/> and brass even seems to have been deliberately boycotted by [[Jewish]] communities in Palestine because of its association with Roman authority.<ref name=r17/>
 
Brass was produced by the cementation process where copper and zinc ore are heated together until zinc vapor is produced which reacts with the copper. There is good archaeological evidence for this process and [[crucible]]s used to produce brass by cementation have been found on [[Roman period]] sites including [[Xanten]]<ref name=r18/> and [[Nidda, Hesse|Nidda]]<ref name=r19/> in [[Germany]], [[Lyon]] in [[France]]<ref name="ReferenceA">Rehren and Martinon Torres 2008, pp. 170–71</ref> and at a number of sites in Britain.<ref>Bayley 1990</ref> They vary in size from tiny acorn sized to large [[amphora]]e like vessels but all have elevated levels of zinc on the interior and are lidded.<ref name="ReferenceA"/> They show no signs of [[slag]] or metal [[prills]] suggesting that zinc minerals were heated to produce zinc vapor which reacted with metallic copper in a [[solid state reaction]]. The fabric of these crucibles is porous, probably designed to prevent a buildup of pressure, and many have small holes in the lids which may be designed to release pressure<ref name="ReferenceA"/> or to add additional zinc minerals near the end of the process. Dioscorides mentioned that zinc minerals were used for both the working and finishing of brass, perhaps suggesting secondary additions.<ref name = ce2003p224>Craddock and Eckstein 2003, p. 224</ref>

Brass made during the early Roman period seems to have varied between 20% and 28% wt zinc.<ref name = ce2003p224/> The high content of zinc in coinage and brass objects declined after the first century AD and it has been suggested that this reflects zinc loss during [[recycling]] and thus an interruption in the production of new brass.<ref name = r15/> However it is now thought this was probably a deliberate change in composition<ref name=r21/> and overall the use of brass increases over this period making up around 40% of all [[copper alloys]] used in the Roman world by the 4th century AD.<ref>Craddock 1978, p. 14</ref>

===Medieval period===
[[File:Renier de Huy JPG0.jpg|thumb|''[[Baptism of Jesus|Baptism of Christ]]'' on the 12th-century [[baptismal font at St Bartholomew's Church, Liège]]]]
Little is known about the production of brass during the centuries immediately after the collapse of the [[Roman Empire]]. Disruption in the trade of tin for bronze from [[Western Europe]] may have contributed to the increasing popularity of brass in the east and by the 6th–7th centuries AD over 90% of [[copper alloy]] artefacts from [[Egypt]] were made of brass.<ref>Craddock, P. T., La Niece, S. C., and Hook, D. (1990). "Brass in the Medieval Islamic World". In Craddock, P. T. (ed.), ''2000 Years of Zinc and Brass''. London: British Museum, p. 73</ref> However other alloys such as low tin bronze were also used and they vary depending on local cultural attitudes, the purpose of the metal and access to zinc, especially between the [[Islamic]] and [[Byzantine]] world.<ref name=r4/> Conversely the use of true brass seems to have declined in Western Europe during this period in favor of [[gunmetal]]s and other mixed alloys<ref>Bayley 1990, p. 22</ref> but by about 1000 brass artefacts are found in [[Scandinavia]]n graves in [[Scotland]],<ref name=r24/> brass was being used in the manufacture of coins in [[Northumbria]]<ref>Gilmore, G. R. and Metcalf, D. M. (1980). "The alloy of the Northumbrian coinage in the mid-ninth century". In Metcalf, D. and Oddy, W. ''Metallurgy in Numismatics'' 1 pp. 83–98</ref> and there is archaeological and historical evidence for the production of [[calamine brass]] in Germany<ref name="r18" /> and [[the Low Countries]],<ref>Day 1990, pp. 123–150</ref> areas rich in [[Calamine (mineral)|calamine]] ore.

These places would remain important centres of brass making throughout the [[Middle Ages]] period,<ref>Day 1990, pp. 124–133</ref> especially [[Dinant]]. Brass objects are still collectively known as ''dinanderie'' in French. The [[baptismal font at St Bartholomew's Church, Liège]] in modern [[Belgium]] (before 1117) is an outstanding masterpiece of [[Romanesque art|Romanesque]] brass casting, though also often described as bronze. The metal of the early 12th-century [[Gloucester Candlestick]] is unusual even by medieval standards in being a mixture of copper, zinc, tin, lead, [[nickel]], iron, [[antimony]] and [[arsenic]] with an unusually large amount of [[silver]], ranging from 22.5% in the base to 5.76% in the pan below the candle. The proportions of this mixture may suggest that the candlestick was made from a hoard of old coins, probably Late Roman.<ref>Noel Stratford, pp. 232, 245, in Zarnecki, George and others; ''English Romanesque Art, 1066–1200'', 1984, Arts Council of Great Britain, {{ISBN|0728703866}}</ref> [[Latten]] is a term for medieval alloys of uncertain and often variable composition often covering decorative borders and similar objects cut from sheet metal, whether of brass or bronze. Especially in [[Tibetan art]], analysis of some objects shows very different compositions from different ends of a large piece. [[Aquamanile]]s were typically made in brass in both the European and Islamic worlds.

[[File:Lion Aquamanile, 1200-1250 AD, German, Lower Saxony, Hildesheim, bronze - Cleveland Museum of Art - DSC08638.JPG|thumb|left|upright|Brass [[aquamanile]] from [[Lower Saxony]], Germany, c. 1250]]
The cementation process continued to be used but literary sources from both Europe and the [[Islamic world]] seem to describe variants of a higher temperature liquid process which took place in open-topped crucibles.<ref>Craddock and Eckstein 2003, pp. 224–25</ref> Islamic cementation seems to have used zinc oxide known as ''tutiya'' or [[tutty]] rather than zinc ores for brass-making, resulting in a metal with lower [[iron]] impurities.<ref>Craddock et al. 1990, 78</ref> A number of Islamic writers and the 13th century [[Italians|Italian]] [[Marco Polo]] describe how this was obtained by [[sublimation (phase transition)|sublimation]] from zinc ores and [[Condensation|condensed]] onto [[clay]] or iron bars, archaeological examples of which have been identified at [[Hindu Kush|Kush]] in Iran.<ref>Craddock et al. 1990, pp. 73–76</ref> It could then be used for brass making or medicinal purposes. In 10th century [[Yemen]] [[Abū Muhammad al-Hasan al-Hamdānī|al-Hamdani]] described how spreading [[al-iglimiya]], probably zinc oxide, onto the surface of molten copper produced tutiya vapor which then reacted with the metal.<ref>Craddock et al. 1990, p. 75</ref> The 13th century Iranian writer [[al-Kashani]] describes a more complex process whereby ''tutiya'' was mixed with [[raisin]]s and gently roasted before being added to the surface of the molten metal. A temporary lid was added at this point presumably to minimize the escape of zinc vapor.<ref>Craddock et al. 1990, p. 76</ref>

In Europe a similar liquid process in open-topped crucibles took place which was probably less efficient than the Roman process and the use of the term tutty by [[Albertus Magnus]] in the 13th century suggests influence from Islamic technology.<ref>Rehren, T (1999) "The same... but different: A juxtaposition of Roman and Medieval brass making in Europe" in Young, S. M. M. (ed.) ''Metals in antiquity'' Oxford: Archaeopress pp. 252–257</ref> The 12th century [[Germans|German]] monk [[Theophilus Presbyter|Theophilus]] described how preheated crucibles were one sixth filled with powdered calamine and [[charcoal]] then topped up with copper and charcoal before being melted, stirred then filled again. The final product was [[casting|cast]], then again melted with calamine. It has been suggested that this second melting may have taken place at a lower temperature to allow more zinc to be [[Absorption (chemistry)|absorbed]].<ref>Craddock and Eckstein 2003, 226</ref> Albertus Magnus noted that the "power" of both calamine and tutty could [[evaporate]] and described how the addition of powdered [[glass]] could create a film to bind it to the metal.<ref>Rehren and Martinon Torres 2008, pp. 176–178</ref> 
German brass making crucibles are known from [[Dortmund]] dating to the 10th century AD and from [[Soest, Germany|Soest]] and [[Schwerte]] in [[Westphalia]] dating to around the 13th century confirm Theophilus' account, as they are open-topped, although [[ceramic]] discs from Soest may have served as loose lids which may have been used to reduce zinc [[evaporation]], and have slag on the interior resulting from a liquid process.<ref>Rehren and Martinon Torres 2008, pp. 173–175</ref>

===Africa===
[[File:Arte yoruba, nigeria, testa da ife, 12-15mo secolo.JPG|thumb|upright|12th century "[[Bronze Head from Ife]]", actually of "heavily leaded zinc-brass"]]
Some of the most famous objects in [[African art]] are the [[lost wax]] castings of West Africa, mostly from what is now [[Nigeria]], produced first by the [[Kingdom of Ife]] and then the [[Benin Empire]]. Though normally described as "bronzes", the [[Benin Bronzes]], now mostly in the [[British Museum]] and other Western collections, and the large portrait heads such as the [[Bronze Head from Ife]] of "heavily leaded zinc-brass" and the [[Bronze Head of Queen Idia]], both also British Museum, are better described as brass, though of variable compositions.<ref>[https://www.britishmuseum.org/research/collection_online/collection_object_details.aspx?objectId=618380 "The Ife Head"] {{Webarchive|url=https://web.archive.org/web/20160920155753/https://www.britishmuseum.org/research/collection_online/collection_object_details.aspx?objectId=618380 |date=20 September 2016 }} on the British Museum collection database. Accessed 26 May 2014</ref>  Work in brass or bronze continued to be important in [[Benin art]] and other West African traditions such as [[Akan goldweights]], where the metal was regarded as a more valuable material than in Europe.

===Renaissance and post-medieval Europe===
The [[Renaissance]] saw important changes to both the theory and practice of brassmaking in Europe. By the 15th century there is evidence for the renewed use of lidded cementation crucibles at [[Zwickau]] in Germany.<ref>Martinon Torres and Rehren 2002, pp. 95–111</ref> These large crucibles were capable of producing c.20&nbsp;kg of brass.<ref>Martinon Torres and Rehren 2002, pp. 105–06</ref> There are traces of slag and pieces of metal on the interior. Their irregular composition suggests that this was a lower temperature, not entirely liquid, process.<ref>Martinon Torres and Rehren 2002, p. 103</ref> The crucible lids had small holes which were blocked with clay plugs near the end of the process presumably to maximize zinc [[absorption (chemistry)|absorption]] in the final stages.<ref>Martinon Torres and Rehren 2002, p. 104</ref> Triangular crucibles were then used to melt the brass for [[casting]].<ref>Martinon Torres and Rehren 2002, p. 100</ref>

16th-century technical writers such as [[Vannoccio Biringuccio|Biringuccio]], [[Lazarus Ercker|Ercker]] and [[Georgius Agricola|Agricola]] described a variety of cementation brass making techniques and came closer to understanding the true nature of the process noting that copper became heavier as it changed to brass and that it became more golden as additional calamine was added.<ref>Martinon Torres and Rehren 2008, 181–82, de Ruette 1995</ref> Zinc metal was also becoming more commonplace. By 1513 metallic zinc [[ingot]]s from India and China were arriving in [[London]] and pellets of zinc condensed in [[Metallurgical furnace|furnace]] flues at the [[Rammelsberg]] in Germany were exploited for cementation brass making from around 1550.<ref>de Ruette 1995, 198</ref>

Eventually it was discovered that metallic zinc could be [[alloy]]ed with copper to make brass, a process known as speltering,<ref name="Craddock and Eckstein 2003, 228">Craddock and Eckstein 2003, 228</ref> and by 1657 the German chemist [[Johann Glauber]] had recognized that calamine was "nothing else but unmeltable zinc" and that zinc was a "half ripe metal".<ref>de Ruette 1995, 198–9</ref> However some earlier high zinc, low iron brasses such as the 1530 Wightman brass memorial [[Commemorative plaque|plaque]] from England may have been made by alloying copper with ''zinc'' and include traces of [[cadmium]] similar to those found in some zinc ingots from China.<ref name="Craddock and Eckstein 2003, 228"/>
 
However, the cementation process was not abandoned, and as late as the early 19th century there are descriptions of [[Solid-state chemistry|solid-state]] cementation in a domed furnace at around 900–950&nbsp;°C and lasting up to 10 hours.<ref>Craddock and Eckstein 2003, 226–27.</ref> The European brass industry continued to flourish into the post medieval period buoyed by innovations such as the 16th century introduction of water powered hammers for the production of wares such as pots.<ref name="Day 1990, 131">Day 1990, p. 131</ref> By 1559 the Germany city of [[Aachen]] alone was capable of producing 300,000 [[centum weight|cwt]] of brass per year.<ref name="Day 1990, 131"/> After several false starts during the 16th and 17th centuries the brass industry was also established in England taking advantage of abundant supplies of cheap copper [[smelted]] in the new [[coal]] fired [[reverberatory furnace]].<ref>Day 1991, pp. 135–144</ref> In 1723 [[Bristol]] brass maker Nehemiah Champion patented the use of [[granulated]] copper, produced by pouring molten metal into cold water.<ref>Day 1990, p. 138</ref> This increased the [[surface area]] of the copper helping it react and zinc contents of up to 33% wt were reported using this new technique.<ref>Craddock and Eckstein 2003, p. 227</ref>

In 1738 Nehemiah's son [[William Champion (metallurgist)|William Champion]] patented a technique for the first industrial scale [[distillation]] of metallic zinc known as ''distillation per descencum'' or "the English process".<ref>Day 1991, pp. 179–181</ref><ref name=r3/> This local zinc was used in speltering and allowed greater control over the zinc content of brass and the production of high-zinc copper alloys which would have been difficult or impossible to produce using cementation, for use in expensive objects such as [[scientific instruments]], [[clock]]s, brass [[buttons]] and [[costume jewelry]].<ref name="Day 1991, 183">Day 1991, p. 183</ref> However Champion continued to use the cheaper calamine cementation method to produce lower-zinc brass<ref name="Day 1991, 183"/> and the archaeological remains of bee-hive shaped cementation furnaces have been identified at his works at [[Warmley]].<ref name=r2/> By the mid-to-late 18th century developments in cheaper zinc distillation such as John-Jaques Dony's horizontal furnaces in Belgium and the reduction of tariffs on zinc<ref>Day 1991, pp. 186–189</ref> as well as demand for [[corrosion]]-resistant high zinc alloys increased the popularity of speltering and as a result cementation was largely abandoned by the mid-19th century.<ref>Day 1991, pp. 192–93, Craddock and Eckstein 2003, p. 228</ref>

==See also==
*[[Brass bed]]
*[[Brass rubbing]]
*[[List of copper alloys]]

== Citations ==
{{Reflist|30em|refs=
<ref name=r1>{{cite journal|doi=10.1186/1753-6561-5-S6-O53|title=Copper surfaces in the ICU reduced the relative risk of acquiring an infection while hospitalized|year=2011|last1=Schmidt|first1=MG|journal=BMC Proceedings|volume=5|issue=Suppl 6|pages=O53|pmc=3239467 |doi-access=free }}</ref>

<ref name=r2>{{cite journal|author=Day, J. |year=1988|title=The Bristol Brass Industry: Furnaces and their associated remains|journal=Journal of Historical Metallurgy|volume= 22|issue=1|page= 24}}</ref>

<ref name=r3>{{cite journal|author1=Dungworth, D.  |author2=White, H. |name-list-style=amp |year=2007|title=Scientific examination of zinc-distillation remains from Warmley, Bristol|journal=Historical Metallurgy|volume=41|pages= 77–83|url=http://cat.inist.fr/?aModele=afficheN&cpsidt=19926763}}</ref>

<ref name=r4>{{cite journal|author=Ponting, M.|year=1999|title=East Meets West in Post-Classical Bet'shan'|journal=Journal of Archaeological Science|volume= 26 |pages= 1311–1321|doi=10.1006/jasc.1998.0373|issue=10}}</ref>

<ref name=r5>{{cite journal|url=http://sciencelinks.jp/j-east/article/200112/000020011201A0425152.php |author=Zhou Weirong |year=2001 |title=The Emergence and Development of Brass Smelting Techniques in China |journal=Bulletin of the Metals Museum of the Japan Institute of Metals |volume=34 |pages=87–98 |url-status=dead |archive-url=https://web.archive.org/web/20120125061916/http://sciencelinks.jp/j-east/article/200112/000020011201A0425152.php |archive-date=2012-01-25 }}</ref>

<ref name="autogenerated1">[http://www.epa.gov/opp00001/factsheets/copper-alloy-products.htm "EPA registers copper-containing alloy products"] {{Webarchive|url=https://web.archive.org/web/20150429114637/http://www.epa.gov/opp00001/factsheets/copper-alloy-products.htm |date=29 April 2015 }}, May 2008</ref>

<ref name=r6>{{cite journal |last1=Michel |first1=James H. |last2=Moran |first2=Wilton |last3=Michels |first3=Harold |last4=Estelle |first4=Adam A. |date=June 20, 2011 |title=Antimicrobial copper displaces stainless steel, germs for medical applications: Alloys have natural germ-killing properties |journal=Tube and Pipe Journal |url=http://www.thefabricator.com/article/metalsmaterials/antimicrobial-copper-displaces-stainless-steel-germs-for--medical-applications|df=dmy-all}}</ref>

<ref name=r7>{{cite journal|author1=Noyce, J. O. |author2=Michels, H. |author3=Keevil, C. W. |year=2006 |title=Potential use of copper surfaces to reduce survival of epidemic methicillin-resistant ''Staphylococcus aureus'' in the healthcare environment |journal=Journal of Hospital Infection |volume=63 |pages=289–297 |pmid=16650507 |url=http://www.coppercanada.ca/antimicrobial/antimicrobial_PDFs/Noyce%20-%20Potential%20use%20of%20cu%20surfaces%20to%20reduce%20survival%20of%20epidemic%20meticillin%20resistant%20staphylococcus%20aureus.pdf |doi=10.1016/j.jhin.2005.12.008 |issue=3 |url-status=dead |archive-url=https://web.archive.org/web/20120117213723/http://www.coppercanada.ca/antimicrobial/antimicrobial_PDFs/Noyce%20-%20Potential%20use%20of%20cu%20surfaces%20to%20reduce%20survival%20of%20epidemic%20meticillin%20resistant%20staphylococcus%20aureus.pdf |archive-date=2012-01-17 |df=dmy-all}}</ref>

<ref name=r8>{{cite journal|author1=Espίrito Santo, Christopher |author2=Taudte, Nadine |author3=Nies, Dietrich H. |author4=and Grass, Gregor |doi=10.1128/AEM.01938-07 |title=Contribution of copper ion resistance to survival of Escherichia coli on metallic copper surfaces|year=2007|journal=Applied and Environmental Microbiology|volume=74|issue=4|pages=977–86|pmid=18156321|pmc=2258564}}</ref>

<ref name=r9>{{cite journal|title=Bacterial Killing by Dry Metallic Copper Surfaces|doi=10.1128/AEM.01599-10|year=2010|last1=Santo|first1=C. E.|last2=Lam|first2=E. W.|last3=Elowsky|first3=C. G.|last4=Quaranta|first4=D.|last5=Domaille|first5=D. W.|last6=Chang|first6=C. J.|last7=Grass|first7=G.|journal=Applied and Environmental Microbiology|volume=77|issue=3|pages=794–802|pmid=21148701|pmc=3028699}}</ref>

<ref name=r10>{{cite web|url=http://www.coppertouchsurfaces.org|title=TouchSurfaces Clinical Trials: Home|work=coppertouchsurfaces.org}}</ref>

<ref name=r11>{{cite journal|author=Craddock, P. T. |year=1978|title=The Composition of Copper Alloys used by the Greek, Etruscan and Roman Civilisations: 3 The Origins and Early Use of Brass|journal=Journal of Archaeological Science|pages=1–16 (8)|doi=10.1016/0305-4403(78)90015-8|volume=5 }}</ref>

<ref name=r13>Montero-Ruis, I. and Perea, A. (2007). "Brasses in the early metallurgy of the Iberian Peninsula". In La Niece, S., Hook, D., and Craddock, P. T. (eds.). ''Metals and mines: Studies in archaeometallurgy''. London: Archetype, pp. 136–40</ref>

<ref name=r14>Craddock, P. T., Burnett, A., and Preston, K. (1980). "Hellenistic copper-based coinage and the origins of brass". In [[William Andrew Oddy|Oddy, W. A.]] (ed.). ''Scientific Studies in Numismatics''. British Museum Occasional Papers 18 pp. 53–64</ref>

<ref name=r15>Caley, E. R. (1964). ''Orichalcum and Related Ancient Alloys''. New York; American Numismatic Society</ref>

<ref name=r16>{{cite journal|author=Ponting, M. |year=2002|title=Roman Military Copper Alloy Artefacts from Israel: Questions of Organisation and Ethnicity|doi=10.1111/1475-4754.t01-1-00086|url=http://www.liv.ac.uk/sace/research/publications/Ponting_Archaeometry_MandG.pdf|journal=Archaeometry|volume=44|issue=4|pages=555–571|bibcode=2002Archa..44..555P }}</ref>

<ref name=r17>{{cite journal|author=Ponting, M. |year=2002|url=http://www.liv.ac.uk/sace/research/publications/Ponting_IAMS_Galillee.pdf |archive-url=https://ghostarchive.org/archive/20221009/http://www.liv.ac.uk/sace/research/publications/Ponting_IAMS_Galillee.pdf |archive-date=2022-10-09 |url-status=live |title=Keeping up with the Roman Romanisation and Copper Alloys in First Revolt Palestine|journal=IAMS|volume= 22|pages=3–6}}</ref>

<ref name=r18>{{cite journal|doi=10.1006/jasc.1999.0402|url=http://www.ucl.ac.uk/archaeology/staff/profiles/rehren/Small%20Size%20Large%20Scale%201999.pdf|title=Small Size, Large Scale Roman Brass Production in Germania Inferior|year=1999|last1=Rehren|first1=T|journal=Journal of Archaeological Science|volume=26|issue=8|pages=1083–1087|bibcode=1999JArSc..26.1083R |access-date=2011-05-12|archive-url=https://web.archive.org/web/20041210001846/http://www.ucl.ac.uk/archaeology/staff/profiles/rehren/Small%20Size%20Large%20Scale%201999.pdf|archive-date=2004-12-10|url-status=dead|df=dmy-all}}</ref>

<ref name=r19>{{cite journal|author=Bachmann, H. |year=1976|title=Crucibles from a Roman Settlement in Germany|journal=Journal of the Historical Metallurgy Society |volume=10|issue=1|pages=34–5}}</ref>

<ref name=r20>{{cite journal|title=355 Copper Alloys Now Approved by EPA as Antimicrobial|date=June 28, 2011|url=http://www.appliancemagazine.com/news.php?article=1498614&zone=0&first=1|journal=Appliance Magazine|df=dmy-all|access-date=23 August 2011|archive-date=18 July 2011|archive-url=https://web.archive.org/web/20110718160110/http://www.appliancemagazine.com/news.php?article=1498614&zone=0&first=1|url-status=dead}}</ref>

<ref name=r21>{{cite journal|author=Dungworth, D |year=1996|title=Caley's 'Zinc Decline' reconsidered|journal=Numismatic Chronicle|volume= 156|pages=228–234}}</ref>

<ref name=r24>{{cite conference |last1=Eremin |first1=Katherine |last2=Graham-Campbell |first2=James |last3=Wilthew |first3=Paul |editor1-last=Biro |editor1-first=K.T |editor2-last=Eremin |editor2-first=K. |date=2002 |title=Analysis of Copper alloy artefacts from Pagan Norse Graves in Scotland |conference=Proceedings of the 31st International Symposium on Archaeometry |series=BAR International Series |publisher=Archaeopress |location=Oxford |pages=342–349}}</ref>

<ref name=r25>Kuhn, Phyllis J. (1983). [http://members.vol.at/schmiede/MsgverSSt.html "Doorknobs: A Source of Nosocomial Infection?"] {{webarchive |url=https://web.archive.org/web/20120216095336/http://members.vol.at/schmiede/MsgverSSt.html |date=16 February 2012 }} ''Diagnostic Medicine''</ref>
}}

== General references ==
{{refbegin}}
*Bayley, J. (1990). "The Production of Brass in Antiquity with Particular Reference to Roman Britain". In Craddock, P. T. (ed.). ''2000 Years of Zinc and Brass''. London: British Museum.
*Craddock, P. T. and Eckstein, K (2003). "Production of Brass in Antiquity by Direct Reduction". In Craddock, P. T. and Lang, J. (eds.). ''Mining and Metal Production Through the Ages''. London: British Museum.
*Day, J. (1990). "Brass and Zinc in Europe from the Middle Ages until the 19th century". In Craddock, P. T. (ed.). ''2000 Years of Zinc and Brass''. London: British Museum.
*Day, J. (1991). "Copper, Zinc and Brass Production". In Day, J. and Tylecote, R. F. (eds.). ''The Industrial Revolution in Metals''. London: The Institute of Metals.
*{{cite journal |last1=Martinon Torres |first1=M. |last2=Rehren |first2=T. |year=2002 |title=Agricola and Zwickau: theory and practice of Renaissance brass production in SE Germany |journal=Historical Metallurgy |volume=36 |issue=2 |pages=95–111}}
*Rehren, T. and Martinon Torres, M. (2008) "Naturam ars imitate: European brassmaking between craft and science". In Martinon-Torres, M. and Rehren, T. (eds.). ''Archaeology, History and Science: Integrating Approaches to Ancient Material''. Left Coast Press.
{{refend}}

==External links==
{{Wiktionary}}
{{Commons category|Brass}}

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[[Category:Brass| ]]
[[Category:Copper alloys]]
[[Category:History of metallurgy]]
[[Category:Zinc alloys]]