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104-496: The cups were discovered in 1852 when the existing bath complex near Vicarello was developed into a more modern one. The cups were found inside a crevice in the rock from which the thermal waters issued, along with a huge votive deposit consisting of ca. 5,000 bronze coins of Greek , Etruscan and Roman origin, including ca. 400 kilograms (880 lb) of aes rude (bronze dating from 8th-4th c. BC), 34 vessels (3 of gold, 25 of silver, 6 of bronze) of which 12 were inscribed (including

208-601: A Vinča culture site in Pločnik ( Serbia ), and believed to have been smelted from a natural tin-copper ore, stannite . Other early examples date to the late 4th millennium BC in Egypt , Susa (Iran) and some ancient sites in China, Luristan (Iran), Tepe Sialk (Iran), Mundigak (Afghanistan), and Mesopotamia (Iraq). Tin bronze was superior to arsenic bronze in that the alloying process could be more easily controlled, and

312-878: 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. During the later part of first millennium BC the use of brass spread across a wide geographical area from Britain and Spain in the west to Iran , and India in the east. 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. The 4th century BC writer Theopompus , quoted by Strabo , describes how heating earth from Andeira in Turkey produced "droplets of false silver", probably metallic zinc, which could be used to turn copper into oreichalkos. In

416-524: 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. 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

520-468: 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 . The King James Bible makes many references to "brass" to translate "nechosheth" (bronze or copper) from Hebrew to English. The earliest brasses may have been natural alloys made by smelting zinc-rich copper ores . By the Roman period brass

624-419: A highly beneficial hard layer of aluminium oxide (Al 2 O 3 ) 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-resistant . The addition of as little as 1% iron to a brass alloy will result in an alloy with

728-657: A lower temperature to allow more zinc to be absorbed . 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. German brass making crucibles are known from Dortmund dating to the 10th century AD and from 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

832-665: 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

936-438: A noticeable magnetic attraction. Brass will corrode in the presence of moisture, chlorides , acetates , 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

1040-455: 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. 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

1144-551: A sharper edge longer. Bronze was still used during the Iron Age, and has continued in use for many purposes to the modern day. There are many different bronze alloys, but typically modern bronze is 88% copper and 12% tin. 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

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1248-506: A total of 1840 Roman miles (2,723.2 km (1,692.1 mi)). The cups are thought to have been manufactured in Spain . The finds are believed to have been part of a votive deposit, consisting of dedications made by the sick who sought a cure at the baths, likely to the protective deity of the location, Apollo . The presence of the cups with the inscribed itinerary has raised several questions. They do not seem to have any relationship to

1352-697: Is a free reed aerophone , also often made from brass. In organ pipes of the reed family, brass strips (called tongues) are used as the reeds, which beat against the shallot (or beat "through" the shallot in the case of a "free" reed). Although not part of the brass section, snare drums 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. The bactericidal properties of brass have been observed for centuries, particularly in marine environments where it prevents biofouling . Depending upon

1456-416: 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

1560-448: Is an outstanding masterpiece of 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

1664-418: Is in modern times. Because historical artworks were often made of brasses (copper and zinc) and bronzes of different metallic compositions, modern museum and scholarly descriptions of older artworks increasingly use the generalized term "copper alloy" instead of the names of individual alloys. This is done (at least in part) to prevent database searches from failing merely because of errors or disagreements in

1768-527: Is likely that 'nehoshet' refers to copper and its alloys with tin, now called bronze. 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

1872-507: Is more malleable than bronze or zinc. The relatively low melting point of brass (900 to 940 °C; 1,650 to 1,720 °F, depending on composition) and its flow characteristics make it a relatively easy material to 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 8.4 to 8.73 g/cm (0.303 to 0.315 lb/cu in). Today, almost 90% of all brass alloys are recycled. Because brass

1976-430: Is not ferromagnetic , ferrous scrap can be separated from it by passing the scrap near a powerful magnet. Brass scrap is melted and recast into 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. Aluminium makes brass stronger and more corrosion-resistant. Aluminium also causes

2080-426: 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 sparks not be struck, such as in fittings and tools used near flammable or explosive materials. Brass

2184-498: Is still commonly used in applications where corrosion resistance and low friction are required, such as locks , hinges , gears , bearings , ammunition casings, zippers , plumbing , hose couplings , valves and electrical plugs and sockets . It is used extensively for musical instruments such as horns and bells . The composition of brass makes it a favorable substitute for copper in costume jewelry and fashion jewelry , as it exhibits greater resistance to corrosion. Brass

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2288-529: Is susceptible to stress corrosion cracking , especially from ammonia or substances containing or releasing ammonia. The problem is sometimes known as season cracking after it was first discovered in brass cartridges used for rifle ammunition during the 1920s in the British Indian Army . The problem was caused by high residual stresses from cold forming of the cases during manufacture, together with chemical attack from traces of ammonia in

2392-453: 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. Bearings are often made of bronze for its friction properties. It can be impregnated with oil to make

2496-541: Is used to make the tone rings of many professional model banjos . 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. Bronze has also been used in coins; most "copper" coins are actually bronze, with about 4 percent tin and 1 percent zinc. As with coins, bronze has been used in

2600-559: The Ancient Greek translation of this term, was later adapted to the Latin aurichalcum meaning "golden copper" which became the standard term for brass. In the 4th century BC Plato knew orichalkos as rare and nearly as valuable as gold and Pliny describes how aurichalcum had come from Cypriot ore deposits which had been exhausted by the 1st century AD. X-ray fluorescence analysis of 39 orichalcum ingots recovered from

2704-599: 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. 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. The Renaissance saw important changes to both

2808-674: The Eastern Mediterranean early copper-zinc alloys are now known in small numbers from a number of 3rd millennium BC sites in the Aegean , Iraq , the United Arab Emirates , Kalmykia , Turkmenistan and Georgia and from 2nd millennium BC sites in western India , Uzbekistan , Iran , Syria , Iraq and Canaan . Isolated examples of copper-zinc alloys are known in China from the 1st century AD, long after bronze

2912-560: 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. Bronze is

3016-571: 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

3120-703: 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. Tiffany Glass Studios, made famous by Louis C. Tiffany commonly referred to his product as favrile glass or " Tiffany glass ," and used bronze in their artisan work for his Tiffany lamps . The largest and most ornate bronze fountain known to be cast in

3224-550: The plaquette , normally a rectangular work of art with a scene in relief , for a collectors' market. Bronze is also associated with eighth wedding anniversaries. 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

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3328-416: The saxhorns . Other wind instruments may be constructed of brass or other metals, and indeed most modern student-model flutes and piccolos are made of some variety of brass, usually a cupronickel alloy similar to nickel silver (also known as German silver) . Clarinets , especially low clarinets such as the contrabass and subcontrabass , are sometimes made of metal because of limited supplies of

3432-453: The saxophones and sarrusophones 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

3536-475: The surface area of the copper helping it react and zinc contents of up to 33% wt were reported using this new technique. In 1738 Nehemiah's son William Champion patented a technique for the first industrial scale distillation of metallic zinc known as distillation per descencum or "the English process". This local zinc was used in speltering and allowed greater control over the zinc content of brass and

3640-682: The 12th-century Romanesque Baptismal font at St Bartholomew's Church, Liège is sometimes described as bronze and sometimes as 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. 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

3744-508: The 13th century Italian Marco Polo describe how this was obtained by sublimation from zinc ores and condensed onto clay or iron bars, archaeological examples of which have been identified at Kush in Iran. It could then be used for brass making or medicinal purposes. In 10th century Yemen al-Hamdani described how spreading al-iglimiya , probably zinc oxide, onto the surface of molten copper produced tutiya vapor which then reacted with

3848-528: The 1st century BC the Greek Dioscorides seems to have recognized a link between zinc minerals and brass describing how Cadmia ( zinc oxide ) was found on the walls of furnaces used to heat either zinc ore or copper and explaining that it can then be used to make brass. By the first century BC brass was available in sufficient supply to use as coinage in Phrygia and Bithynia , and after

3952-515: The Augustan currency reform of 23 BC it was also used to make Roman dupondii and sestertii . The uniform use of brass for coinage and military equipment across the Roman world may indicate a degree of state involvement in the industry, and brass even seems to have been deliberately boycotted by Jewish communities in Palestine because of its association with Roman authority. Brass

4056-563: The European and Islamic worlds. 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. 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. A number of Islamic writers and

4160-457: The German chemist Johann Glauber had recognized that calamine was "nothing else but unmeltable zinc" and that zinc was a "half ripe metal". However some earlier high zinc, low iron brasses such as the 1530 Wightman brass memorial 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. However,

4264-585: The Germany city of Aachen alone was capable of producing 300,000 cwt of brass per year. 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 . In 1723 Bristol brass maker Nehemiah Champion patented the use of granulated copper, produced by pouring molten metal into cold water. This increased

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4368-545: The Roman process and the use of the term tutty by Albertus Magnus in the 13th century suggests influence from Islamic technology. The 12th century German monk 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 cast , then again melted with calamine. It has been suggested that this second melting may have taken place at

4472-399: 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 . The archaeological period in which bronze was

4576-440: 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 the cases, and storing the cartridges elsewhere. Other phases than α, β and γ are ε, a hexagonal intermetallic CuZn 3 , and η, a solid solution of copper in zinc. Although forms of brass have been in use since prehistory , its true nature as

4680-653: The average brass key, new or old, exceeded the California Proposition 65 limits by an average factor of 19, assuming handling twice a day. 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. Also in California, lead-free materials must be used for "each component that comes into contact with

4784-452: The barrel. 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 )

4888-432: The battle of David and Goliath in I Samuel 17:5-6;38 (also see II Chron. 12:10). Brass 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, but copper typically has the larger proportion, generally 66% copper and 34% zinc. In use since prehistoric times, it is a substitutional alloy : atoms of

4992-577: The brass used to construct the instrument bodies, but still workable with simple hand tools—a boon to quick repairs. The mouthpieces 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 instruments , most notably cymbals , gongs , and orchestral (tubular) bells (large "church" bells are normally made of bronze ). Small handbells and " jingle bells " are also commonly made of brass. The harmonica

5096-413: 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. 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 boundaries in

5200-491: The candlestick was made from a hoard of old coins, probably Late Roman. 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. Aquamaniles were typically made in brass in both

5304-422: The cementation process was not abandoned, and as late as the early 19th century there are descriptions of solid-state cementation in a domed furnace at around 900–950 °C and lasting up to 10 hours. 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. By 1559

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5408-427: The coins from the original discovery were not recorded. Dated to the 1st century AD, the cups are cylindrical in form and range in height from 9.5–11.5 cm (3.7–4.5 in), and are similar in shape to Roman milestones. They are inscribed on their outside with an itinerary that goes from Gades (modern Cadiz ) overland to Rome, including all the 104 stopping points along the way and the distances between them, for

5512-670: The cups themselves), and various metal objects such as plates, small statues in bronze and other materials. Most of the finds from the deposit, including the cups, are to be found in the Museo Nazionale Romano , while a few of the numismatic finds are in the Vatican Museums . The collection belonged originally to the Kircher Museum , which was later incorporated into the Museo Nazionale. Many of

5616-434: The dense, fine-grained tropical hardwoods traditionally preferred for smaller woodwinds . For the same reason, some low clarinets, bassoons and contrabassoons 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

5720-605: The divinity of the location and in fact the route on the cups, which includes the Via Flaminia in Italy, does not include Vicarello, instead passing dozens of kilometers to the east, through Narnia (modern Narni ) and Ocriculum (modern Otricoli ). One hypothesis is that the cups were dedicated to Apollo as a thank offering for the accomplished trip, by merchants from Gades who traveled to Rome for business. This hypothesis does not explain why these merchants would have preferred

5824-469: The end of the process presumably to maximize zinc absorption in the final stages. Triangular crucibles were then used to melt the brass for casting . 16th-century technical writers such as Biringuccio , Ercker and 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

5928-446: The end of the process. Dioscorides mentioned that zinc minerals were used for both the working and finishing of brass, perhaps suggesting secondary additions. Brass made during the early Roman period seems to have varied between 20% and 28% wt zinc. 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

6032-579: 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. "Naval brass", for use in seawater, contains 40% zinc but also 1% tin. The tin addition suppresses zinc leaching. The NSF International requires brasses with more than 15% zinc, used in piping and plumbing fittings , to be dezincification-resistant. The high malleability and workability, relatively good resistance to corrosion , and traditionally attributed acoustic properties of brass, have made it

6136-626: 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. In October 1999, the California State Attorney General sued 13 key manufacturers and distributors over lead content. In laboratory tests, state researchers found

6240-519: 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; 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

6344-545: 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

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6448-637: 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. Indian Hindu artisans from

6552-774: 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. 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. Conversely the use of true brass seems to have declined in Western Europe during this period in favor of gunmetals and other mixed alloys but by about 1000 brass artefacts are found in Scandinavian graves in Scotland , brass

6656-429: 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. Though bronze is generally harder than wrought iron , with Vickers hardness of 60–258 vs. 30–80, 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

6760-418: The interior and are lidded. 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 or to add additional zinc minerals near

6864-647: The interior resulting from a liquid process. 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

6968-405: 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. By the 8th–7th century BC Assyrian cuneiform tablets mention the exploitation of the "copper of the mountains" and this may refer to "natural" brass. "Oreikhalkon" (mountain copper),

7072-824: The main alloying ingredient. They are commonly used in architectural applications. Plastic bronze contains a significant quantity of lead, which makes for improved plasticity, and was possibly used by the ancient Greeks in ship construction. 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. Other bronze alloys include aluminium bronze , phosphor bronze , manganese bronze, bell metal , arsenical bronze , speculum metal , bismuth bronze , and cymbal alloys . 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

7176-462: 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:

7280-673: The massive bronze doors to the United States Supreme Court Building in Washington, DC. 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,

7384-407: The metal. The 13th century Iranian writer al-Kashani describes a more complex process whereby tutiya was mixed with raisins 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. In Europe a similar liquid process in open-topped crucibles took place which was probably less efficient than

7488-585: The more general term " copper alloy ". Brass has long been a popular material for its bright gold-like appearance and is still used for drawer pulls and 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 turning and milling machines), durability, and 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

7592-488: The much longer land route to the faster and likely less expensive one by sea. A second hypothesis is that these cups were donated by travelers from Spain to the Roman senator Lucius Junius Caesennius Paetus , a relative of the emperor Domitian who had a villa in the town of Vicarello. These merchants would then later have dedicated the cups to Apollo. Bronze Bronze is an alloy consisting primarily of copper , commonly with about 12–12.5% tin and often with

7696-650: The naming of historic copper alloys. 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: 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

7800-424: The patina layer was formed, it may protect the underlying brass from further damage. 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,

7904-581: 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

8008-424: 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

8112-456: 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 , clocks , brass buttons and costume jewelry . However Champion continued to use the cheaper calamine cementation method to produce lower-zinc brass and the archaeological remains of bee-hive shaped cementation furnaces have been identified at his works at Warmley . By

8216-528: The production of new brass. However it is now thought this was probably a deliberate change in composition 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. 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

8320-452: The proprietary Oilite and similar material for bearings. Aluminum bronze is hard and wear-resistant, and is used for bearings and machine tool ways. The Doehler Die Casting Co. of Toledo, Ohio were known for the production of Brastil , a high tensile corrosion resistant bronze alloy. The Seagram Building on New York City 's Park Avenue is the "iconic glass box sheathed in bronze, designed by Mies van der Rohe ." The Seagram Building

8424-454: 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

8528-690: The resulting alloy was stronger and easier to cast. Also, unlike those of arsenic , metallic tin and the fumes from tin refining are not toxic . Tin became the major non-copper ingredient of bronze in the late 3rd millennium BC. 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 with other regions. Tin sources and trade in ancient times had

8632-478: The shipping of tin around the Mediterranean and from Britain, limiting supplies and raising prices. As the art of working in iron improved, iron became cheaper and improved in quality. As later cultures advanced from hand- wrought iron to machine- forged iron (typically made with trip hammers powered by water), blacksmiths also learned how to make steel . Steel is stronger and harder than bronze and holds

8736-476: 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. These large crucibles were capable of producing c.20 kg of brass. 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. The crucible lids had small holes which were blocked with clay plugs near

8840-469: The tin content in a bell or cymbal rises, the timbre drops. 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. Bronzes of various metallurgical properties are widely used in struck idiophones around

8944-448: 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. Both bronze and brass may include small proportions of a range of other elements including arsenic , lead , phosphorus , aluminium , manganese and silicon . Historically, the distinction between the two alloys has been less consistent and clear, and increasingly museums use

9048-442: The type and concentration of pathogens and the medium they are in, brass kills these microorganisms within a few minutes to hours of contact. A large number of independent studies 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. Brass

9152-439: 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. 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 . Bronze statues were regarded as

9256-568: The usual metal of choice for construction of musical instruments whose acoustic resonators 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 instruments , or simply 'the brass', these include the trombone , tuba , trumpet , cornet , flugelhorn , baritone horn , euphonium , tenor horn , and French horn , and many other " horns ", many in variously sized families, such as

9360-525: The wetted surface of pipes and 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. Dezincification-resistant ( 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, chlorides present or deviating water qualities ( soft water ) play

9464-419: 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

9568-657: The world was by the Roman Bronze Works and General Bronze Corporation in 1952. The material used for the fountain, known as statuary bronze, is a quaternary alloy made of copper, zinc, tin, and lead, and traditionally golden brown in color. This was made for the Andrew W. Mellon Memorial Fountain in Federal Triangle in Washington, DC. Another example of the massive, ornate design projects of bronze, and attributed to General Bronze/Roman Bronze Works were

9672-710: 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. 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). Bell bronze/B20

9776-409: The zinc loss. "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. Another such material is gunmetal , from

9880-531: Was added. Zinc metal was also becoming more commonplace. By 1513 metallic zinc ingots from India and China were arriving in London and pellets of zinc condensed in furnace flues at the Rammelsberg in Germany were exploited for cementation brass making from around 1550. Eventually it was discovered that metallic zinc could be alloyed with copper to make brass, a process known as speltering, and by 1657

9984-454: Was being deliberately produced from metallic copper and zinc minerals using the cementation process, the product of which was calamine brass , and variations on this method continued until the mid-19th century. It was eventually replaced by speltering , the direct alloying of copper and zinc metal which was introduced to Europe in the 16th century. Brass has sometimes historically been referred to as "yellow copper". In West Asia and

10088-733: Was being used in the manufacture of coins in Northumbria and there is archaeological and historical evidence for the production of calamine brass in Germany and the Low Countries , areas rich in calamine ore. These places would remain important centres of brass making throughout the Middle Ages period, 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)

10192-525: Was made out of copper and arsenic or from naturally or artificially mixed ores of those metals, forming arsenic bronze . The earliest known arsenic-copper-alloy artifacts come from a Yahya Culture (Period V 3800-3400 BCE) site, at Tal-i-Iblis on the Iranian plateau , and were smelted from native arsenical copper and copper-arsenides, such as algodonite and domeykite . The earliest tin-copper-alloy artifact has been dated to c.  4650 BC , in

10296-474: 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

10400-424: Was not only the most expensive building of its time — $ 36 million — but it was the first building in the world with floor-to-ceiling glass walls. Mies van der Rohe achieved the crisp edges that were custom-made with specific detailing by General Bronze and "even the screws that hold in the fixed glass-plate windows were made of brass." Bronze is widely used for casting bronze sculptures . Common bronze alloys have

10504-481: 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

10608-671: 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 crucibles used to produce brass by cementation have been found on Roman period sites including Xanten and Nidda in Germany , Lyon in France and at a number of sites in Britain. They vary in size from tiny acorn sized to large amphorae like vessels but all have elevated levels of zinc on

10712-593: Was the first time that an entire building was sheathed in bronze. The General Bronze Corporation fabricated 3,200,000 pounds (1,600 tons) of bronze at its plant in Garden City, New York . The Seagram Building is a 38-story, 516-foot bronze-and- topaz -tinted glass building. The building looks like a "squarish 38-story tower clad in a restrained curtain wall of metal and glass." "Bronze was selected because of its color, both before and after aging, its corrosion resistance, and its extrusion properties. In 1958, it

10816-482: Was widely used. 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. These may be "natural alloys" manufactured by smelting zinc rich copper ores in redox conditions. Many have similar tin contents to contemporary bronze artefacts and it is possible that some copper-zinc alloys were accidental and perhaps not even distinguished from copper. However

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