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Bronze

Bronze is an alloy consisting primarily of copper, commonly with about 12–12.5% tin and often with the addition of other metals (including aluminium, manganese, nickel, or zinc) and sometimes non-metals, such as phosphorus, or metalloids such as arsenic or silicon. These additions produce a range of alloys that may be harder than copper alone, or have other useful properties, such as strength, ductility, or machinability.

Various examples of bronze artworks throughout history

The archaeological period in which bronze was the hardest metal in widespread use is known as the Bronze Age. The beginning of the Bronze Age in western Eurasia and India is conventionally dated to the mid-4th millennium BC (~3500 BC), and to the early 2nd millennium BC in China;[1] elsewhere it gradually spread across regions. The Bronze Age was followed by the Iron Age starting about 1300 BC and reaching most of Eurasia by about 500 BC, although bronze continued to be much more widely used than it is in modern times.

Because historical artworks were often made of brasses (copper and zinc) and bronzes with different compositions, modern museum and scholarly descriptions of older artworks increasingly use the generalized term "copper alloy" instead.[2]

Etymology edit

 
Houmuwu ding (Chinese: 后母戊鼎; pinyin: Hòumǔwù dǐng), the heaviest Chinese ritual bronze ever found; 1300–1046 BC; National Museum of China (Beijing). This ding's name is based on the inscription in the bronze interior wall, which reads Hòumǔwù, meaning 'Queen Mother Wu'

The word bronze (1730–1740) is borrowed from Middle French bronze (1511), itself borrowed from Italian bronzo 'bell metal, brass' (13th century, transcribed in Medieval Latin as bronzium) from either:

  • bróntion, back-formation from Byzantine Greek brontēsíon (βροντησίον, 11th century), perhaps from Brentḗsion (Βρεντήσιον, 'Brindisi', reputed for its bronze;[3][4] or originally:
  • in its earliest form from Old Persian birinj, (برنج, 'brass', modern berenj) and piring (پرنگ) 'copper',[5] from which also came Georgian brinǯi (ბრინჯი), Turkish pirinç, and Armenian brinj (բրինձ), also meaning 'bronze'.

History edit

 
Hoard of bronze socketed axes from the Bronze Age found in modern Germany. This was the top tool of the period, and also seems to have been used as a store of value.
 
Roman bronze nails with magical signs and inscriptions, 3rd-4th century AD.

The discovery of bronze enabled people to create metal objects that were harder and more durable than previously possible. Bronze tools, weapons, armor, and building materials such as decorative tiles were harder and more durable than their stone and copper ("Chalcolithic") predecessors. Initially, bronze was made out of copper and arsenic, forming arsenic bronze, or from naturally or artificially mixed ores of copper and arsenic.[6]

The earliest artifacts so far known come from the Iranian plateau, in the 5th millennium BC, and are smelted from native arsenical copper and copper-arsenides, such as algodonite and domeykite.[7] The earliest tin-copper-alloy artifact has been dated to c. 4650 BC, in a Vinča culture site in Pločnik (Serbia), and believed to have been smelted from a natural tin-copper ore, stannite.[8] Other early examples date to the late 4th millennium BC in Egypt, Susa (Iran) and some ancient sites in China, Luristan (Iran),[7] Tepe Sialk (Iran),[7] Mundigak (Afghanistan),[7] and Mesopotamia (Iraq).[citation needed]

Tin bronze was superior to arsenic bronze in that the alloying process could be more easily controlled, and the resulting alloy was stronger and easier to cast. Also, unlike those of arsenic, metallic tin and fumes from tin refining are not toxic.

Tin became the major non-copper ingredient of bronze in the late 3rd millennium BC.[9]

Ores of copper and the far rarer tin are not often found together (exceptions include Cornwall in the United Kingdom, one ancient site in Thailand and one in Iran), so serious bronze work has always involved trade. Tin sources and trade in ancient times had a major influence on the development of cultures. In Europe, a major source of tin was the British deposits of ore in Cornwall, which were traded as far as Phoenicia in the eastern Mediterranean.

In many parts of the world, large hoards of bronze artifacts are found, suggesting that bronze also represented a store of value and an indicator of social status. In Europe, large hoards of bronze tools, typically socketed axes (illustrated above), are found, which mostly show no signs of wear. With Chinese ritual bronzes, which are documented in the inscriptions they carry and from other sources, the case is clear. These were made in enormous quantities for elite burials, and also used by the living for ritual offerings.

Transition to iron edit

Though bronze is generally harder than wrought iron, with Vickers hardness of 60–258 vs. 30–80,[10] the Bronze Age gave way to the Iron Age after a serious disruption of the tin trade: the population migrations of around 1200–1100 BC reduced the shipping of tin around the Mediterranean and from Britain, limiting supplies and raising prices.[11] As the art of working in iron improved, iron became cheaper and improved in quality. As cultures advanced from hand-wrought iron to machine-forged iron (typically made with trip hammers powered by water), blacksmiths learned how to make steel. Steel is stronger and harder than bronze and holds a sharper edge longer.[12]

Bronze was still used during the Iron Age, and has continued in use for many purposes to the modern day.

Composition edit

 
Bronze bell with a visible crystallite structure.

There are many different bronze alloys, but typically modern bronze is 88% copper and 12% tin.[13] 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, turbines 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 Baptismal font at St Bartholomew's Church, Liège is described as both bronze and brass.

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

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.[14][15]

Plastic bronze contains a significant quantity of lead, which makes for improved plasticity[16] possibly used by the ancient Greeks in their ship construction.[17]

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.[18]

Other bronze alloys include aluminium bronze, phosphor bronze, manganese bronze, bell metal, arsenical bronze, speculum metal, bismuth bronze, and cymbal alloys.

Properties edit

Copper-based alloys have lower melting points than steel or iron and are more readily produced from their constituent metals. They are generally about 10 percent denser than steel, although alloys using aluminum or silicon may be slightly less dense. Bronze is a better conductor of heat and electricity than most steels. The cost of copper-base alloys is generally higher than that of steels but lower than that of nickel-base alloys.

Bronzes are typically ductile alloys, considerably less brittle than cast iron. Copper and its alloys have a huge variety of uses that reflect their versatile physical, mechanical, and chemical properties. Some common examples are the high electrical conductivity of pure copper, low-friction properties of bearing bronze (bronze that has a high lead content— 6–8%), resonant qualities of bell bronze (20% tin, 80% copper), and resistance to corrosion by seawater of several bronze alloys.

The melting point of bronze varies depending on the ratio of the alloy components and is about 950 °C (1,742 °F). Bronze is usually nonmagnetic, but certain alloys containing iron or nickel may have magnetic properties.

Typically bronze oxidizes only superficially; once a copper oxide (eventually becoming copper carbonate) layer is formed, the underlying metal is protected from further corrosion. This can be seen on statues from the Hellenistic period. If copper chlorides are formed, a corrosion-mode called "bronze disease" will eventually completely destroy it.[19]

Uses edit

 
Bronze weight with an inscribed imperial order, Qin dynasty
 
Industrial products of the Bunting Brass and Bronze Company, 1912

Bronze, or bronze-like alloys and mixtures, were used for coins over a longer period. Bronze was especially suitable for use in boat and ship fittings prior to the wide employment of stainless steel owing to its combination of toughness and resistance to salt water corrosion. Bronze is still commonly used in ship propellers and submerged bearings.

In the 20th century, silicon was introduced as the primary alloying element, creating an alloy with wide application in industry and the major form used in contemporary statuary. Sculptors may prefer silicon bronze because of the ready availability of silicon bronze brazing rod, which allows color-matched repair of defects in castings. Aluminum is also used for the structural metal aluminum bronze.

Bronze parts are tough and typically used for bearings, clips, electrical connectors and springs.

Bronze also has low friction against dissimilar metals, making it important for cannons prior to modern tolerancing, where iron cannonballs would otherwise stick in the barrel.[20] It is still widely used today for springs, bearings, bushings, automobile transmission pilot bearings, and similar fittings, and is particularly common in the bearings of small electric motors. Phosphor bronze is particularly suited to precision-grade bearings and springs. It is also used in guitar and piano strings.

Unlike steel, bronze struck against a hard surface will not generate sparks, so it (along with beryllium copper) is used to make hammers, mallets, wrenches and other durable tools to be used in explosive atmospheres or in the presence of flammable vapors. Bronze is used to make bronze wool for woodworking applications where steel wool would discolor oak.

Phosphor bronze is used for ships' propellers, musical instruments, and electrical contacts.[21] Bearings are often made of bronze for its friction properties. It can be impregnated with oil to make the proprietary Oilite and similar material for bearings. Aluminum bronze is hard and wear-resistant, and is used for bearings and machine tool ways.[22]

Sculptures edit

Bronze is widely used for casting bronze sculptures. Common bronze alloys have the unusual and desirable property of expanding slightly just before they set, thus filling the finest details of a mould. Then, as the bronze cools, it shrinks a little, making it easier to separate from the mould.[23]

The Assyrian king Sennacherib (704–681 BC) claims to have been the first to cast monumental bronze statues (of up to 30 tonnes) using two-part moulds instead of the lost-wax method.[24]

Bronze statues were regarded as the highest form of sculpture in Ancient Greek art, though survivals are few, as bronze was a valuable material in short supply in the Late Antique and medieval periods. Many of the most famous Greek bronze sculptures are known through Roman copies in marble, which were more likely to survive.

In India, bronze sculptures from the Kushana (Chausa hoard) and Gupta periods (Brahma from Mirpur-Khas, Akota Hoard, Sultanganj Buddha) and later periods (Hansi Hoard) have been found.[25] Indian Hindu artisans from the period of the Chola empire in Tamil Nadu used bronze to create intricate statues via the lost-wax casting method with ornate detailing depicting the deities of Hinduism. The art form survives to this day, with many silpis, craftsmen, working in the areas of Swamimalai and Chennai.

In antiquity other cultures also produced works of high art using bronze. For example: in Africa, the bronze heads of the Kingdom of Benin; in Europe, Grecian bronzes typically of figures from Greek mythology; in east Asia, Chinese ritual bronzes of the Shang and Zhou dynasty—more often ceremonial vessels but including some figurine examples.

Bronze continues into modern times as one of the materials of choice for monumental statuary.

Mirrors edit

 
Decorated back of a Celtic bronze mirror, 120-80 BC, St Keverne, England

Before it became possible to produce glass with acceptably flat surfaces, bronze was a standard material for mirrors. Bronze was used for this purpose in many parts of the world, probably based on independent discoveries.

Bronze mirrors survive from the Egyptian Middle Kingdom (2040–1750 BC), and China from at least c. 550 BC. In Europe, the Etruscans were making bronze mirrors in the sixth century BC, and Greek and Roman mirrors followed the same pattern. Although other materials such as speculum metal had come into use, and Western glass mirrors had largely taken over, bronze mirrors were still being made in Japan and elsewhere in the eighteenth century, and are still made on a small scale in Kerala, India.

Musical instruments edit

 
Chinese bells:Bianzhong of Marquis Yi of Zeng, Spring and Autumn period (476–221 BC)
 
Singing bowls from the 16th to 18th centuries. Annealed bronze continues to be made in the Himalayas

Bronze is the preferred metal for bells in the form of a high tin bronze alloy known as bell metal, which is typically about 23% tin.

Nearly all professional cymbals are made from bronze, which gives a desirable balance of durability and timbre. Several types of bronze are used, commonly B20 bronze, which is roughly 20% tin, 80% copper, with traces of silver, or the tougher B8 bronze made from 8% tin and 92% copper. As the tin content in a bell or cymbal rises, the timbre drops.[26]

Bronze is also used for the windings of steel and nylon strings of various stringed instruments such as the double bass, piano, harpsichord, and guitar. Bronze strings are commonly reserved on pianoforte for the lower pitch tones, as they possess a superior sustain quality to that of high-tensile steel.[27]

Bronzes of various metallurgical properties are widely used in struck idiophones around the world, notably bells, singing bowls, gongs, cymbals, and other idiophones from Asia. Examples include Tibetan singing bowls, temple bells of many sizes and shapes, Javanese gamelan, and other bronze musical instruments. The earliest bronze archeological finds in Indonesia date from 1–2 BC, including flat plates probably suspended and struck by a wooden or bone mallet.[27][28] Ancient bronze drums from Thailand and Vietnam date back 2,000 years. Bronze bells from Thailand and Cambodia date back to 3600 BC.

Some companies are now making saxophones from phosphor bronze (3.5 to 10% tin and up to 1% phosphorus content).[29] Bell bronze/B20 is used to make the tone rings of many professional model banjos.[30] The tone ring is a heavy (usually 3 lb; 1.4 kg) folded or arched metal ring attached to a thick wood rim, over which a skin, or most often, a plastic membrane (or head) is stretched – it is the bell bronze that gives the banjo a crisp powerful lower register and clear bell-like treble register.[citation needed]

Biblical references edit

There are over 125 references to bronze ('nehoshet'), which appears to be the Hebrew word used for copper and any of its alloys. However, the Old Testament era Hebrews are not thought to have had the capability to manufacture zinc (needed to make brass) and so it is likely that 'nehoshet' refers to copper and its alloys with tin, now called bronze.[31] In the King James Version, there is no use of the word 'bronze' and 'nehoshet' was translated as 'brass'. Modern translations use 'bronze'. Bronze (nehoshet) was used widely in the Tabernacle for items such as the bronze altar (Exodus Ch.27), bronze laver (Exodus Ch.30), utensils, and mirror (Exodus Ch.38). It was mentioned in the account of Moses holding up a bronze snake on a pole in Numbers Ch.21. In First Kings, it is mentioned that Hiram was very skilled in working with bronze, and he made many furnishings for Solomon's Temple including pillars, capitals, stands, wheels, bowls, and plates, some of which were highly decorative (see I Kings 7:13-47). Bronze was also widely used as battle armor and helmet, as in the battle of David and Goliath in I Samuel 17:5-6;38 (also see II Chron. 12:10).

Coins and medals edit

 
Medal of the Emperor John VIII Palaiologos during his visit to Florence, by Pisanello (1438). The legend reads, in Greek: "John the Palaiologos, basileus and autokrator of the Romans".

Bronze has also been used in coins; most "copper" coins are actually bronze, with about 4 percent tin and 1 percent zinc.[32]

As with coins, bronze has been used in the manufacture of various types of medals for centuries, and "bronze medals" are known in contemporary times for being awarded for third place in sporting competitions and other events. The term is now often used for third place even when no actual bronze medal is awarded. The usage in part arose from the trio of gold, silver and bronze to represent the first three Ages of Man in Greek mythology: the Golden Age, when men lived among the gods; the Silver age, where youth lasted a hundred years; and the Bronze Age, the era of heroes. It was first adopted for a sports event at the 1904 Summer Olympics. At the 1896 event, silver was awarded to winners and bronze to runners-up, while at 1900 other prizes were given rather than medals.

Bronze is the normal material for the related form of the plaquette, normally a rectangular work of art with a scene in relief, for a collectors' market.

See also edit

References edit

  1. ^ Thorp, Robert L. (2013). China in the Early Bronze Age: Shang Civilization. University of Pennsylvania Press.[page needed]
  2. ^ "British Museum, "Scope Note" for "copper alloy"". British Museum. from the original on 18 August 2014. Retrieved 14 September 2014.
  3. ^ Kahane, Henry; Kahane, Renée (1981). "Byzantium's Impact on the West: The Linguistic Evidence". Illinois Classical Studies. 6 (2): 395.
  4. ^ Originally Berthelot, M.P.E. (1888). "Sur le nom du bronze chez les alchimistes grecs". Revue archéologique (in French): 294–98.
  5. ^ Originally Lokotsch, Karl (1927). Etymologisches Wörterbuch der europäischen Wörter orientalischen Ursprungs (in German). Heidelberg: Carl Winter's Universitätsbuchhandlung. p. 1657.
  6. ^ Tylecote, R.F. (1992). . London: Maney Publishing, for the Institute of Materials. ISBN 978-1-902653-79-2. Archived from the original on 2015-04-02.
  7. ^ a b c d Thornton, C.; Lamberg-Karlovsky, C.C.; Liezers, M.; Young, S.M.M. (2002). "On pins and needles: tracing the evolution of copper-based alloying at Tepe Yahya, Iran, via ICP-MS analysis of Common-place items". Journal of Archaeological Science. 29 (12): 1451–60. Bibcode:2002JArSc..29.1451T. doi:10.1006/jasc.2002.0809.
  8. ^ Radivojević, Miljana; Rehren, Thilo (December 2013). "Tainted ores and the rise of tin bronzes in Eurasia, c. 6500 years ago". Antiquity Publications Ltd. Archived from the original on 2014-02-05.
  9. ^ Kaufman, Brett. "Metallurgy and Ecological Change in the Ancient Near East". Backdirt: Annual Review. 2011: 86.
  10. ^ Smithells Metals Reference Book, 8th Edition, ch. 22
  11. ^ Cramer, Clayton E. (10 December 1995). (PDF). claytoncramer.com. Archived from the original (PDF) on 2010-12-28.
  12. ^ Sherby, O. D.; Wadsworth, J. (2000). (PDF). Thermec 2000. Las Vegas, Nevada: U.S. Department of Commerce. Archived from the original (PDF) on 2007-06-26. Retrieved 24 August 2022.
  13. ^ Knapp, Brian. (1996) Copper, Silver and Gold. Reed Library, Australia.
  14. ^ "Copper alloys". from the original on 11 September 2013. Retrieved 14 September 2014.
  15. ^ "CDA UNS Standard Designations for Wrought and Cast Copper and Copper Alloys: Introduction". from the original on 24 September 2013. Retrieved 14 September 2014.
  16. ^ "plastic bronze". The Free Encyclopedia. Retrieved 24 August 2022.
  17. ^ Adams, Jonathan R. (2012). "The Belgammel Ram, a Hellenistic-Roman BronzeProembolionFound off the Coast of Libya: test analysis of function, date and metallurgy, with a digital reference archive" (PDF). International Journal of Nautical Archaeology. 42 (1): 60–75. CiteSeerX 10.1.1.738.4024. doi:10.1111/1095-9270.12001. S2CID 39339094. (PDF) from the original on 2016-08-28.
  18. ^ ASTM B124 / B124M – 15. ASTM International. 2015.
  19. ^ . The Joukowsky Institute for Archaeology Classroom. Archived from the original on 26 February 2015. Retrieved 14 September 2014.
  20. ^ Alavudeen, A.; Venkateshwaran, N.; Winowlin Jappes, J. T. (1 January 2006). A Textbook of Engineering Materials and Metallurgy. Firewall Media. pp. 136–. ISBN 978-81-7008-957-5. from the original on 10 June 2016. Retrieved 25 June 2013.
  21. ^ "Resources: Standards & Properties – Copper & Copper Alloy Microstructures: Phosphor Bronze". Copper Development Association Inc. from the original on 2015-12-08. Retrieved 24 August 2022.
  22. ^ "Resources: Standards & Properties – Copper & Copper Alloy Microstructures: Aluminum Bronzes". Copper Development Association Inc. from the original on 2013-12-05. Retrieved 24 August 2022.
  23. ^ Savage, George (1968). A Concise History of Bronzes. New York: Frederick A. Praeger, Inc. Publishers. p. 17.
  24. ^ for a translation of his inscription see the appendix in Dalley, Stephanie (2013). The Mystery of the Hanging Garden of Babylon: an elusive World Wonder traced. OUP. ISBN 978-0-19-966226-5.
  25. ^ Indian bronze masterpieces: the great tradition: specially published for the Festival of India, Asharani Mathur, Sonya Singh, Festival of India, Brijbasi Printers, Dec 1, 1988
  26. ^ Von Falkenhausen, Lothar (1993). Suspended Music: Chime-Bells in the Culture of Bronze Age China. Berkeley and Los Angeles: University of California Press. p. 106. ISBN 978-0-520-07378-4. from the original on 2016-05-26.
  27. ^ a b McCreight, Tim (1992). Metals technic: a collection of techniques for metalsmiths. Brynmorgen Press. ISBN 0-9615984-3-3.[page needed]
  28. ^ LaPlantz, David (1991). Jewelry – Metalwork 1991 Survey: Visions – Concepts – Communication. S. LaPlantz. ISBN 0-942002-05-9.[page needed]
  29. ^ . Archived from the original on 11 August 2014. Retrieved 18 September 2014.
  30. ^ Siminoff, Roger H. (2008). Siminoff's Luthiers Glossary. New York: Hal Leonard. p. 13. ISBN 9781423442929.
  31. ^ Meschel, Susan V. "Nehoshet: Copper, Bronze or Brass? Which are Plausible in the Tanakh?". Jewish Bible Quarterly. Retrieved 24 August 2022.
  32. ^ "bronze | alloy". Encyclopædia Britannica (Online ed.). from the original on 2016-07-30. Retrieved 2016-07-21.

External links edit

  • Bronze at Curlie
  • (archived 16 December 2006)
  • (archived 23 May 2009)
  • "Flash animation of the lost-wax casting process". James Peniston Sculpture. Retrieved 2008-11-03.
  • (archived 16 April 2016)

bronze, this, article, about, metal, alloy, other, uses, disambiguation, alloy, consisting, primarily, copper, commonly, with, about, often, with, addition, other, metals, including, aluminium, manganese, nickel, zinc, sometimes, metals, such, phosphorus, meta. This article is about the metal alloy For other uses see Bronze disambiguation Bronze is an alloy consisting primarily of copper commonly with about 12 12 5 tin and often with the addition of other metals including aluminium manganese nickel or zinc and sometimes non metals such as phosphorus or metalloids such as arsenic or silicon These additions produce a range of alloys that may be harder than copper alone or have other useful properties such as strength ductility or machinability Various examples of bronze artworks throughout history The archaeological period in which bronze was the hardest metal in widespread use is known as the Bronze Age The beginning of the Bronze Age in western Eurasia and India is conventionally dated to the mid 4th millennium BC 3500 BC and to the early 2nd millennium BC in China 1 elsewhere it gradually spread across regions The Bronze Age was followed by the Iron Age starting about 1300 BC and reaching most of Eurasia by about 500 BC although bronze continued to be much more widely used than it is in modern times Because historical artworks were often made of brasses copper and zinc and bronzes with different compositions modern museum and scholarly descriptions of older artworks increasingly use the generalized term copper alloy instead 2 Contents 1 Etymology 2 History 2 1 Transition to iron 3 Composition 4 Properties 5 Uses 5 1 Sculptures 5 2 Mirrors 5 3 Musical instruments 5 4 Biblical references 5 5 Coins and medals 6 See also 7 References 8 External linksEtymology edit nbsp Houmuwu ding Chinese 后母戊鼎 pinyin Houmǔwu dǐng the heaviest Chinese ritual bronze ever found 1300 1046 BC National Museum of China Beijing This ding s name is based on the inscription in the bronze interior wall which reads Houmǔwu meaning Queen Mother Wu The word bronze 1730 1740 is borrowed from Middle French bronze 1511 itself borrowed from Italian bronzo bell metal brass 13th century transcribed in Medieval Latin as bronzium from either brontion back formation from Byzantine Greek brontesion bronthsion 11th century perhaps from Brentḗsion Brenthsion Brindisi reputed for its bronze 3 4 or originally in its earliest form from Old Persian birinj برنج brass modern berenj and piring پرنگ copper 5 from which also came Georgian brinǯi ბრინჯი Turkish pirinc and Armenian brinj բրինձ also meaning bronze History edit nbsp Hoard of bronze socketed axes from the Bronze Age found in modern Germany This was the top tool of the period and also seems to have been used as a store of value nbsp Roman bronze nails with magical signs and inscriptions 3rd 4th century AD The discovery of bronze enabled people to create metal objects that were harder and more durable than previously possible Bronze tools weapons armor and building materials such as decorative tiles were harder and more durable than their stone and copper Chalcolithic predecessors Initially bronze was made out of copper and arsenic forming arsenic bronze or from naturally or artificially mixed ores of copper and arsenic 6 The earliest artifacts so far known come from the Iranian plateau in the 5th millennium BC and are smelted from native arsenical copper and copper arsenides such as algodonite and domeykite 7 The earliest tin copper alloy artifact has been dated to c 4650 BC in a Vinca culture site in Plocnik Serbia and believed to have been smelted from a natural tin copper ore stannite 8 Other early examples date to the late 4th millennium BC in Egypt Susa Iran and some ancient sites in China Luristan Iran 7 Tepe Sialk Iran 7 Mundigak Afghanistan 7 and Mesopotamia Iraq citation needed Tin bronze was superior to arsenic bronze in that the alloying process could be more easily controlled and the resulting alloy was stronger and easier to cast Also unlike those of arsenic metallic tin and fumes from tin refining are not toxic Tin became the major non copper ingredient of bronze in the late 3rd millennium BC 9 Ores of copper and the far rarer tin are not often found together exceptions include Cornwall in the United Kingdom one ancient site in Thailand and one in Iran so serious bronze work has always involved trade Tin sources and trade in ancient times had a major influence on the development of cultures In Europe a major source of tin was the British deposits of ore in Cornwall which were traded as far as Phoenicia in the eastern Mediterranean In many parts of the world large hoards of bronze artifacts are found suggesting that bronze also represented a store of value and an indicator of social status In Europe large hoards of bronze tools typically socketed axes illustrated above are found which mostly show no signs of wear With Chinese ritual bronzes which are documented in the inscriptions they carry and from other sources the case is clear These were made in enormous quantities for elite burials and also used by the living for ritual offerings Transition to iron edit Though bronze is generally harder than wrought iron with Vickers hardness of 60 258 vs 30 80 10 the Bronze Age gave way to the Iron Age after a serious disruption of the tin trade the population migrations of around 1200 1100 BC reduced the shipping of tin around the Mediterranean and from Britain limiting supplies and raising prices 11 As the art of working in iron improved iron became cheaper and improved in quality As cultures advanced from hand wrought iron to machine forged iron typically made with trip hammers powered by water blacksmiths learned how to make steel Steel is stronger and harder than bronze and holds a sharper edge longer 12 Bronze was still used during the Iron Age and has continued in use for many purposes to the modern day Composition edit nbsp Bronze bell with a visible crystallite structure There are many different bronze alloys but typically modern bronze is 88 copper and 12 tin 13 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 turbines 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 Baptismal font at St Bartholomew s Church Liege is described as both bronze and brass In the Bronze Age two forms of bronze were commonly used classic bronze about 10 tin was used in casting and mild bronze about 6 tin was hammered from ingots to make sheets Bladed weapons were mostly cast from classic bronze while helmets and armor were hammered from mild bronze 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 14 15 Plastic bronze contains a significant quantity of lead which makes for improved plasticity 16 possibly used by the ancient Greeks in their ship construction 17 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 18 Other bronze alloys include aluminium bronze phosphor bronze manganese bronze bell metal arsenical bronze speculum metal bismuth bronze and cymbal alloys Properties editCopper based alloys have lower melting points than steel or iron and are more readily produced from their constituent metals They are generally about 10 percent denser than steel although alloys using aluminum or silicon may be slightly less dense Bronze is a better conductor of heat and electricity than most steels The cost of copper base alloys is generally higher than that of steels but lower than that of nickel base alloys Bronzes are typically ductile alloys considerably less brittle than cast iron Copper and its alloys have a huge variety of uses that reflect their versatile physical mechanical and chemical properties Some common examples are the high electrical conductivity of pure copper low friction properties of bearing bronze bronze that has a high lead content 6 8 resonant qualities of bell bronze 20 tin 80 copper and resistance to corrosion by seawater of several bronze alloys The melting point of bronze varies depending on the ratio of the alloy components and is about 950 C 1 742 F Bronze is usually nonmagnetic but certain alloys containing iron or nickel may have magnetic properties Typically bronze oxidizes only superficially once a copper oxide eventually becoming copper carbonate layer is formed the underlying metal is protected from further corrosion This can be seen on statues from the Hellenistic period If copper chlorides are formed a corrosion mode called bronze disease will eventually completely destroy it 19 Uses edit nbsp Bronze weight with an inscribed imperial order Qin dynasty nbsp Industrial products of the Bunting Brass and Bronze Company 1912Bronze or bronze like alloys and mixtures were used for coins over a longer period Bronze was especially suitable for use in boat and ship fittings prior to the wide employment of stainless steel owing to its combination of toughness and resistance to salt water corrosion Bronze is still commonly used in ship propellers and submerged bearings In the 20th century silicon was introduced as the primary alloying element creating an alloy with wide application in industry and the major form used in contemporary statuary Sculptors may prefer silicon bronze because of the ready availability of silicon bronze brazing rod which allows color matched repair of defects in castings Aluminum is also used for the structural metal aluminum bronze Bronze parts are tough and typically used for bearings clips electrical connectors and springs Bronze also has low friction against dissimilar metals making it important for cannons prior to modern tolerancing where iron cannonballs would otherwise stick in the barrel 20 It is still widely used today for springs bearings bushings automobile transmission pilot bearings and similar fittings and is particularly common in the bearings of small electric motors Phosphor bronze is particularly suited to precision grade bearings and springs It is also used in guitar and piano strings Unlike steel bronze struck against a hard surface will not generate sparks so it along with beryllium copper is used to make hammers mallets wrenches and other durable tools to be used in explosive atmospheres or in the presence of flammable vapors Bronze is used to make bronze wool for woodworking applications where steel wool would discolor oak Phosphor bronze is used for ships propellers musical instruments and electrical contacts 21 Bearings are often made of bronze for its friction properties It can be impregnated with oil to make the proprietary Oilite and similar material for bearings Aluminum bronze is hard and wear resistant and is used for bearings and machine tool ways 22 Sculptures edit Main article Bronze sculpture See also Ormolu Bronze is widely used for casting bronze sculptures Common bronze alloys have the unusual and desirable property of expanding slightly just before they set thus filling the finest details of a mould Then as the bronze cools it shrinks a little making it easier to separate from the mould 23 The Assyrian king Sennacherib 704 681 BC claims to have been the first to cast monumental bronze statues of up to 30 tonnes using two part moulds instead of the lost wax method 24 Bronze statues were regarded as the highest form of sculpture in Ancient Greek art though survivals are few as bronze was a valuable material in short supply in the Late Antique and medieval periods Many of the most famous Greek bronze sculptures are known through Roman copies in marble which were more likely to survive In India bronze sculptures from the Kushana Chausa hoard and Gupta periods Brahma from Mirpur Khas Akota Hoard Sultanganj Buddha and later periods Hansi Hoard have been found 25 Indian Hindu artisans from the period of the Chola empire in Tamil Nadu used bronze to create intricate statues via the lost wax casting method with ornate detailing depicting the deities of Hinduism The art form survives to this day with many silpis craftsmen working in the areas of Swamimalai and Chennai In antiquity other cultures also produced works of high art using bronze For example in Africa the bronze heads of the Kingdom of Benin in Europe Grecian bronzes typically of figures from Greek mythology in east Asia Chinese ritual bronzes of the Shang and Zhou dynasty more often ceremonial vessels but including some figurine examples Bronze continues into modern times as one of the materials of choice for monumental statuary nbsp The Dancing Girl an Harappan artwork 2400 1900 BC bronze height 10 8 cm National Museum New Delhi India nbsp Ritual tripod cauldron ding c 13th century BC bronze height with handles 25 4 cm Metropolitan Museum of Art New York City nbsp Ancient Egyptian statuette of a Kushite pharaoh 713 664 BC bronze precious metal leaf height 7 6 cm width 3 2 cm depth 3 6 cm Metropolitan Museum of Art nbsp Etruscan tripod base for a thymiaterion incense burner 475 450 BC bronze height 11 cm Metropolitan Museum of Art nbsp The Artemision Bronze 460 450 BC bronze height 2 1 m National Archaeological Museum Athens nbsp Ancient Egyptian statuette of Isis and Horus 305 30 BC solid cast of bronze 4 8 10 3 cm Cleveland Museum of Art Cleveland Ohio US nbsp Ancient Greek statue of Eros sleeping 3rd 2nd century BC bronze 41 9 35 6 85 2 cm Metropolitan Museum of Art nbsp Gupta sculpture of Buddha offering protection late 6th early 7th century copper alloy height 47 cm width 15 6 cm diameter 14 3 cm from India probably Bihar Metropolitan Museum of Art nbsp French or South Netherlandish Medieval caldron 13th or 14th century bronze and wrought iron height 37 5 cm diameter 34 3 cm Metropolitan Museum of Art nbsp Pair of French Rococo firedogs chenets c 1750 gilt bronze dimensions of the first 52 7 x 48 3 x 26 7 cm of the second 45 1 x 49 1 x 24 8 cm Metropolitan Museum of Art nbsp French Neoclassical mantel clock pendule de cheminee 1757 1760 gilded and patinated bronze oak veneered with ebony white enamel with black numerals and other materials 48 3 69 9 27 9 cm Metropolitan Museum of Art nbsp Pair of French Chinoiserie firedogs 1760 1770 gilt bronze height each 41 9 cm Metropolitan Museum of Art nbsp Pair of Chinese vases with French Rococo mounts the vases early 18th century the mounts 1760 70 hard paste porcelain with gilt bronze mounts 32 4 x 16 5 x 12 4 cm Metropolitan Museum of Art nbsp French Neoclassical mantel clock Pendule Uranie 1764 1770 case patinated bronze and gilded bronze Dial white enamel movement brass and steel 71 1 52 1 26 7 cm Metropolitan Museum of Art nbsp Pair of mounted vases vase a monter 1765 70 soft paste porcelain and French gilt bronze 28 9 x 17 1 cm Metropolitan Museum of Art nbsp Winter by Jean Antoine Houdon 1787 bronze 143 5 x 39 1 x 50 5 cm height of the pedestal 86 4 cm Metropolitan Museum of ArtMirrors edit nbsp Decorated back of a Celtic bronze mirror 120 80 BC St Keverne EnglandMain article Bronze mirror Before it became possible to produce glass with acceptably flat surfaces bronze was a standard material for mirrors Bronze was used for this purpose in many parts of the world probably based on independent discoveries Bronze mirrors survive from the Egyptian Middle Kingdom 2040 1750 BC and China from at least c 550 BC In Europe the Etruscans were making bronze mirrors in the sixth century BC and Greek and Roman mirrors followed the same pattern Although other materials such as speculum metal had come into use and Western glass mirrors had largely taken over bronze mirrors were still being made in Japan and elsewhere in the eighteenth century and are still made on a small scale in Kerala India Musical instruments edit nbsp Chinese bells Bianzhong of Marquis Yi of Zeng Spring and Autumn period 476 221 BC nbsp Singing bowls from the 16th to 18th centuries Annealed bronze continues to be made in the HimalayasBronze is the preferred metal for bells in the form of a high tin bronze alloy known as bell metal which is typically about 23 tin Nearly all professional cymbals are made from bronze which gives a desirable balance of durability and timbre Several types of bronze are used commonly B20 bronze which is roughly 20 tin 80 copper with traces of silver or the tougher B8 bronze made from 8 tin and 92 copper As the tin content in a bell or cymbal rises the timbre drops 26 Bronze is also used for the windings of steel and nylon strings of various stringed instruments such as the double bass piano harpsichord and guitar Bronze strings are commonly reserved on pianoforte for the lower pitch tones as they possess a superior sustain quality to that of high tensile steel 27 Bronzes of various metallurgical properties are widely used in struck idiophones around the world notably bells singing bowls gongs cymbals and other idiophones from Asia Examples include Tibetan singing bowls temple bells of many sizes and shapes Javanese gamelan and other bronze musical instruments The earliest bronze archeological finds in Indonesia date from 1 2 BC including flat plates probably suspended and struck by a wooden or bone mallet 27 28 Ancient bronze drums from Thailand and Vietnam date back 2 000 years Bronze bells from Thailand and Cambodia date back to 3600 BC Some companies are now making saxophones from phosphor bronze 3 5 to 10 tin and up to 1 phosphorus content 29 Bell bronze B20 is used to make the tone rings of many professional model banjos 30 The tone ring is a heavy usually 3 lb 1 4 kg folded or arched metal ring attached to a thick wood rim over which a skin or most often a plastic membrane or head is stretched it is the bell bronze that gives the banjo a crisp powerful lower register and clear bell like treble register citation needed Biblical references edit There are over 125 references to bronze nehoshet which appears to be the Hebrew word used for copper and any of its alloys However the Old Testament era Hebrews are not thought to have had the capability to manufacture zinc needed to make brass and so it is likely that nehoshet refers to copper and its alloys with tin now called bronze 31 In the King James Version there is no use of the word bronze and nehoshet was translated as brass Modern translations use bronze Bronze nehoshet was used widely in the Tabernacle for items such as the bronze altar Exodus Ch 27 bronze laver Exodus Ch 30 utensils and mirror Exodus Ch 38 It was mentioned in the account of Moses holding up a bronze snake on a pole in Numbers Ch 21 In First Kings it is mentioned that Hiram was very skilled in working with bronze and he made many furnishings for Solomon s Temple including pillars capitals stands wheels bowls and plates some of which were highly decorative see I Kings 7 13 47 Bronze was also widely used as battle armor and helmet as in the battle of David and Goliath in I Samuel 17 5 6 38 also see II Chron 12 10 Coins and medals edit nbsp Medal of the Emperor John VIII Palaiologos during his visit to Florence by Pisanello 1438 The legend reads in Greek John the Palaiologos basileus and autokrator of the Romans Bronze has also been used in coins most copper coins are actually bronze with about 4 percent tin and 1 percent zinc 32 As with coins bronze has been used in the manufacture of various types of medals for centuries and bronze medals are known in contemporary times for being awarded for third place in sporting competitions and other events The term is now often used for third place even when no actual bronze medal is awarded The usage in part arose from the trio of gold silver and bronze to represent the first three Ages of Man in Greek mythology the Golden Age when men lived among the gods the Silver age where youth lasted a hundred years and the Bronze Age the era of heroes It was first adopted for a sports event at the 1904 Summer Olympics At the 1896 event silver was awarded to winners and bronze to runners up while at 1900 other prizes were given rather than medals Bronze is the normal material for the related form of the plaquette normally a rectangular work of art with a scene in relief for a collectors market See also editArt object Bell founding Bronze and brass ornamental work Bronzing Chinese bronze inscriptions Dezincification resistant brass French Empire mantel clock List of copper alloys Ormolu Seagram Building the first office building in the world to use extruded bronze on a facade General Bronze Corporation Tiffany lamp UNS C69100 Tungum a bronze alloy of copper aluminium nickel tin and zinc Yoruba artReferences edit Thorp Robert L 2013 China in the Early Bronze Age Shang Civilization University of Pennsylvania Press page needed British Museum Scope Note for copper alloy British Museum Archived from the original on 18 August 2014 Retrieved 14 September 2014 Kahane Henry Kahane Renee 1981 Byzantium s Impact on the West The Linguistic Evidence Illinois Classical Studies 6 2 395 Originally Berthelot M P E 1888 Sur le nom du bronze chez les alchimistes grecs Revue archeologique in French 294 98 Originally Lokotsch Karl 1927 Etymologisches Worterbuch der europaischen Worter orientalischen Ursprungs in German Heidelberg Carl Winter s Universitatsbuchhandlung p 1657 Tylecote R F 1992 A History of Metallurgy Second Edition London Maney Publishing for the Institute of Materials ISBN 978 1 902653 79 2 Archived from the original on 2015 04 02 a b c d Thornton C Lamberg Karlovsky C C Liezers M Young S M M 2002 On pins and needles tracing the evolution of copper based alloying at Tepe Yahya Iran via ICP MS analysis of Common place items Journal of Archaeological Science 29 12 1451 60 Bibcode 2002JArSc 29 1451T doi 10 1006 jasc 2002 0809 Radivojevic Miljana Rehren Thilo December 2013 Tainted ores and the rise of tin bronzes in Eurasia c 6500 years ago Antiquity Publications Ltd Archived from the original on 2014 02 05 Kaufman Brett Metallurgy and Ecological Change in the Ancient Near East Backdirt Annual Review 2011 86 Smithells Metals Reference Book 8th Edition ch 22 Cramer Clayton E 10 December 1995 What Caused The Iron Age PDF claytoncramer com Archived from the original PDF on 2010 12 28 Sherby O D Wadsworth J 2000 Ancient Blacksmiths the Iron Age Damascus Steels and Modern Metallurgy PDF Thermec 2000 Las Vegas Nevada U S Department of Commerce Archived from the original PDF on 2007 06 26 Retrieved 24 August 2022 Knapp Brian 1996 Copper Silver and Gold Reed Library Australia Copper alloys Archived from the original on 11 September 2013 Retrieved 14 September 2014 CDA UNS Standard Designations for Wrought and Cast Copper and Copper Alloys Introduction Archived from the original on 24 September 2013 Retrieved 14 September 2014 plastic bronze The Free Encyclopedia Retrieved 24 August 2022 Adams Jonathan R 2012 The Belgammel Ram a Hellenistic Roman BronzeProembolionFound off the Coast of Libya test analysis of function date and metallurgy with a digital reference archive PDF International Journal of Nautical Archaeology 42 1 60 75 CiteSeerX 10 1 1 738 4024 doi 10 1111 1095 9270 12001 S2CID 39339094 Archived PDF from the original on 2016 08 28 ASTM B124 B124M 15 ASTM International 2015 Bronze Disease Archaeologies of the Greek Past The Joukowsky Institute for Archaeology Classroom Archived from the original on 26 February 2015 Retrieved 14 September 2014 Alavudeen A Venkateshwaran N Winowlin Jappes J T 1 January 2006 A Textbook of Engineering Materials and Metallurgy Firewall Media pp 136 ISBN 978 81 7008 957 5 Archived from the original on 10 June 2016 Retrieved 25 June 2013 Resources Standards amp Properties Copper amp Copper Alloy Microstructures Phosphor Bronze Copper Development Association Inc Archived from the original on 2015 12 08 Retrieved 24 August 2022 Resources Standards amp Properties Copper amp Copper Alloy Microstructures Aluminum Bronzes Copper Development Association Inc Archived from the original on 2013 12 05 Retrieved 24 August 2022 Savage George 1968 A Concise History of Bronzes New York Frederick A Praeger Inc Publishers p 17 for a translation of his inscription see the appendix in Dalley Stephanie 2013 The Mystery of the Hanging Garden of Babylon an elusive World Wonder traced OUP ISBN 978 0 19 966226 5 Indian bronze masterpieces the great tradition specially published for the Festival of India Asharani Mathur Sonya Singh Festival of India Brijbasi Printers Dec 1 1988 Von Falkenhausen Lothar 1993 Suspended Music Chime Bells in the Culture of Bronze Age China Berkeley and Los Angeles University of California Press p 106 ISBN 978 0 520 07378 4 Archived from the original on 2016 05 26 a b McCreight Tim 1992 Metals technic a collection of techniques for metalsmiths Brynmorgen Press ISBN 0 9615984 3 3 page needed LaPlantz David 1991 Jewelry Metalwork 1991 Survey Visions Concepts Communication S LaPlantz ISBN 0 942002 05 9 page needed www sax co uk Archived from the original on 11 August 2014 Retrieved 18 September 2014 Siminoff Roger H 2008 Siminoff s Luthiers Glossary New York Hal Leonard p 13 ISBN 9781423442929 Meschel Susan V Nehoshet Copper Bronze or Brass Which are Plausible in the Tanakh Jewish Bible Quarterly Retrieved 24 August 2022 bronze alloy Encyclopaedia Britannica Online ed Archived from the original on 2016 07 30 Retrieved 2016 07 21 External links editBronze at Wikipedia s sister projects nbsp Definitions from Wiktionary nbsp Media from Commons nbsp Texts from Wikisource nbsp Data from Wikidata Bronze at Curlie Bronze bells archived 16 December 2006 Lost Wax Found Bronze lost wax casting explained archived 23 May 2009 Flash animation of the lost wax casting process James Peniston Sculpture Retrieved 2008 11 03 Viking Bronze Ancient and Early Medieval bronze casting archived 16 April 2016 Retrieved from https en wikipedia org w index php title Bronze amp oldid 1191935113, wikipedia, wiki, book, books, library,

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