Editing Bronze (section)

==Composition==
[[File:Bronze bell with visible material structure.jpg|thumb|left|Bronze bell with a visible [[crystallite]] structure.]]
There are many different bronze alloys, but typically modern bronze is about 88% [[copper]] and 12% [[tin]].<ref>Knapp, Brian. (1996) ''Copper, Silver and Gold''. Reed Library, Australia.</ref> ''Alpha bronze'' consists of the alpha [[solid solution]] of tin in copper. Alpha bronze alloys of 4–5% tin are used to make coins, springs, [[turbine]]s and blades. Historical "bronzes" are highly variable in composition, as most metalworkers probably used whatever scrap was on hand; the metal of the 12th-century English [[Gloucester Candlestick]] is bronze containing a mixture of copper, [[zinc]], tin, [[lead]], [[nickel]], [[iron]], [[antimony]], [[arsenic]] and an unusually large amount of [[silver]] – between 22.5% in the base and 5.76% in the pan below the candle. The proportions of this mixture suggest that the candlestick was made from a hoard of old coins. The 13th-century [[Benin Bronzes]] are in fact brass, and the 12th-century [[Romanesque art|Romanesque]] [[Baptismal font at St Bartholomew's Church, Liège]] is sometimes described as bronze and sometimes as [[brass]].

During the Bronze Age, two forms of bronze were commonly used: "classic bronze", about 10% tin, was used in casting; "mild bronze", about 6% tin, was hammered from ingots to make sheets. Bladed weapons were primarily cast from classic bronze while helmets and armor were hammered from mild bronze.

Modern commercial bronze (90% copper and 10% zinc) and architectural bronze (57% copper, 3% lead, 40% zinc) are more properly regarded as brass alloys because they contain zinc as the main alloying ingredient. They are commonly used in architectural applications.<ref>{{cite web|url=http://www.copper.org/applications/architecture/arch_dhb/copper_alloys/intro.html|title=Copper alloys|access-date=14 September 2014|url-status=live|archive-url=https://web.archive.org/web/20130911022109/http://www.copper.org/applications/architecture/arch_dhb/copper_alloys/intro.html|archive-date=11 September 2013}}</ref><ref>{{cite web|url=http://www.copper.org/resources/properties/standard-designations/introduction.html|title=CDA UNS Standard Designations for Wrought and Cast Copper and Copper Alloys: Introduction|access-date=14 September 2014|url-status=live|archive-url=https://web.archive.org/web/20130924132326/http://www.copper.org/resources/properties/standard-designations/introduction.html|archive-date=24 September 2013}}</ref> Plastic bronze contains a significant quantity of lead, which makes for improved plasticity,<ref>{{cite encyclopedia |url=http://encyclopedia2.thefreedictionary.com/plastic+bronze |title=plastic bronze |encyclopedia=The Free Encyclopedia |access-date=24 August 2022}}</ref> and may have been used by the ancient Greeks in ship construction.<ref>{{cite journal | doi=10.1111/1095-9270.12001 | volume=42 | issue=1 | title=The Belgammel Ram, a Hellenistic-Roman BronzeProembolionFound off the Coast of Libya: test analysis of function, date and metallurgy, with a digital reference archive | year=2012 | journal=International Journal of Nautical Archaeology | pages=60–75 | last1=Adams | first1=Jonathan R. | url=http://www.don-simmonds.co.uk/oliver/ijna12001.pdf | url-status=live | archive-url=https://web.archive.org/web/20160828133417/http://www.don-simmonds.co.uk/oliver/ijna12001.pdf | archive-date=2016-08-28 | citeseerx=10.1.1.738.4024 | s2cid=39339094 }}</ref> {{vanchor|[[Silicon bronze]]}} has a composition of Si: 2.80–3.80%, Mn: 0.50–1.30%, Fe: 0.80% max., Zn: 1.50% max., Pb: 0.05% max., Cu: balance.<ref>{{Cite book|title = ASTM B124 / B124M – 15|publisher = ASTM International|year = 2015}}</ref> Other bronze alloys include [[aluminium bronze]], [[phosphor bronze]], manganese bronze, [[bell metal]], [[arsenical bronze]], [[speculum metal]], [[bismuth bronze]], and [[cymbal alloys]].