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Bronze Sheet from Luristan

Bronze Sheet from Luristan


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LURISTAN BRONZES ii. CHRONOLOGY

A few stray Luristan bronzes were acquired by European museums as early as the second half of the 19th century. At that time, however, their origin was unknown and scholars attributed them to various regions and cultures in the Near East. It was not until the late 1920s, when they started to appear en mass in the antiquities markets of Tehran, Paris, London, and New York, that it became established that they originated in Luristan. Private collectors as well as museums started building their own collections of bronzes, although reliable information remained scarce. For several decades, one had to depend largely on the study of the objects themselves and on information provided by the antiquities trade.

The first documented Luristan bronze acquired by a European museum, &ldquoa master of animals idol,&rdquo was purchased in 1854 by the British Museum (Moorey, 1974, p. 7). The first publication about a Luristan bronze in a scholarly journal dates from 1918. It attributed a Luristan horse bit with decorated cheek pieces to Armenia. The item, acquired by the British Museum, came from a Parsee family in Bombay (Read, 1918, pl. A/Moorey, 1974, pl. VIIA). In 1922, Michael Ivanovich Rostovtzeff ascribed a series of idols in the British Museum and in the Louvre to the Cimmerians or Scythians and claimed that they had been found in Cappadocia (Rostovtzeff, 1922, pp. 11, 40, 56, pl. II, V.3), an unsupported claim that was still accepted as credible as late as 1963 by some leading scholars (Portratz, 1963, pp. 124-25). Large-scale plundering of Luristan graveyards is thought to have started in the late 1920s, and by 1930 Luristan was widely recognized as the source of the bronzes (Potratz, 1963, pp. 124-25 Muscarella, 1988, p. 113). Nevertheless, other attributions continued to be suggested, mainly as a result of the confusion concerning the precise definition of Luristan bronzes or by reliance on dubious information. Most of these so-called Luristan bronzes from other regions are simply not of Luristan style (e.g. Smith, 1952, from Arabia). In other cases, unconfirmed claims of finds of Luristan style bronzes in other regions were at the origin of far-fetched conclusions. An iron sword in Luristan style, for example, which was said to come from the Pontus area of the Black Sea, instigated Ernst Herzfeld to ascribe all swords of this type to the Pontus (Herzfeld, 1941, pp. 134-36, fig. 252), an idea later picked up by Roman Ghirshman. Well aware of the fact that such swords, of which nearly ninety specimens are known, were found in Luristan, he suggested that they were produced in the Pontus but came with the Cimmerians to Luristan (Ghirshman, 1983, p. 29, 76-78, 83-85, pl. I-II Muscarella, 1989, p. 352-53).

In the late 1920s, when the looting of Luristan graveyards started, the region was still strongly dominated by its tribal structure and the central Iranian government had only a limited control on local overlords. The looting and commercialization of the antiquities trade was a well-organized clandestine business. Local khans controlled the activities and it was dangerous to interfere in their affairs, as it is evident from a report on the looting of a graveyard at Cheshmeh Māhi (Ča&scaronma māhi) in 1959, witnessed by Louis Vanden Berghe, and Yolande Maleki (Maleki, 1964 Overlaet, 2003, pp. 31-33, fig. 19-21). Archaeologists like Aurel Stein, eager to excavate in Luristan, were lured away from sites of interest (Demandt-Mortensen, 1993, pp. 72, 74, note 11, pp. 382-84, fig. 6, 443). The information on the place and circumstances of the discovery of Luristan bronzes generally came from the antiquities dealers. At a time when it was common practice for leading art historians like Arthur Upham Pope and archaeologists like André Godard, Roman Ghirshman, Friedrich Sarre, and Ernst Herzfeld to build up private collections of their own, and therefore to be in close contact with the antiquities trade, hearsay information could easily find its way into scientific literature.

Luristan bronzes were already widely sought as collectible from the first years when the looting started. Reports in popular periodicals such as the Illustrated London News (9 contributions by Herzfeld, Pope, and Stark between 1929 and 1932) and exhibitions like the famous International Exhibition of Persian Art in 1931 at the galleries of the Royal Academy of Arts at Burlington House, London, further promoted the interest of the general public and scholars alike. Several of the bronzes exhibited at the Burlington House Exhibition were acquired by the Royal Museums of Art and History in Brussels (Speleers, 1931, pp. 59-60, fig. 26). Museums and private collectors competed in strengthening their collections. With little or no first-hand information available from field research, scholars had to turn to private and public collections to study the Luristan culture. In the first volume of his bibliography on the archaeology of Iran until 1977, Louis Vanden Berghe lists no fewer than 138 publications of 54 private and museum collections (Vanden Berghe et al, 1979, pp. 212-23). It must be clear that the present survey can only indicate tendencies in this research and cannot provide a full survey of all the studies and methodologies used. Many of the earlier and most extensive private collections were later wholly or partially acquired by museums. One of the most important collections, many of whose items were published by prominent scholars, belonged to Mohsen Foroughi (See FORŪḠĪ MOḤSEN ii. ART COLLECTION). He donated some of his objects to the Louvre Museum and the remainder was transferred after the 1979 Revolution from his Tehran residence to the National Archeological Museum in Tehran.

Different approaches can be distinguished in the early studies, each with its own specific merits and flaws. Some studies concentrated on a particular type of object, others on complete collections or on the general chronology.

When Godard published his survey of Luristan bronzes (Godard, 1931), there existed no clear definition of what a Luristan bronze was. His work presented canonical Iron Age bronzes next to general west Iranian and third millennium bronzes. At the time, he ascribed the Luristan bronzes to Kassites who would have retreated from Babylonia to Luristan and would have led a nomadic lifestyle similar to that of the Luristan nomads of his day (Godard, 1931, pp. 13-18). Other scholars such as Ghirshman would later ascribe the Luristan bronzes to Cimmerians. These ethnic and lifestyle attributions all remained unsubstantiated, and although criticized by many (for a survey see Muscarella, 1988, pp. 116-17 Overlaet, 2003, pp. 233-34), were often repeated uncritically in later literature on the subject.

In spite of the above reservations, various detailed studies focusing on specific objects or groups of objects have made it possible to place these objects in a more precise chronological and cultural setting and have enhanced our general understanding of the concept of canonical Luristan bronzes. Particularly noteworthy are Hanns Albert Portratz&rsquos studies on Luristan idols (Potratz, 1955), and horse-bits with decorated cheek-pieces (Potratz, 1941, 1941-42, 1966), in which he proposed stylistic and chronological developments that were largely confirmed later by evidence from excavations. The general tendency was to date canonical Luristan bronzes such as idols and horse-bits to the late second and the first half of the first millenniumBC.E. Against this general consensus, Claude Schaeffer in his Stratigraphie Comparée et Chronologie de l&rsquoAsie Occidentale (1948), proposed a Bronze Age date between 1500 and 1200BC.E. (&ldquoLuristan Récent&rdquo) for all canonical bronzes. He only accepted a minimal continuation into the Early Iron Age to explain the presence of bimetallic weaponry (Schaeffer, 1948, pp. 479-82, fig. 263-67). It illustrates the difficulties involved in stylistic comparative studies in the absence of data from excavations. Nevertheless, when Edith Porada presented another survey of the Luristan chronology based on an art historical analysis, she placed the Luristan bronzes in four stylistic phases, starting before 1000BC.E and lasting until about 600/650BC.E (Porada, 1964).

Luristan antiquities from unknown provenances continued to flood the antiquities markets in large quantities after World War II. There was, however, a growing awareness of the problems associated with the general methodology used by most scholars. For many years, one had depended on the study of individual objects with dubious information culled from the antiquities market. The trade, however, had resorted to various solutions to meet the dwindling supply and the growing demand for Luristan bronzes. As early as the 1930s, bronze objects of other regions and periods had been increasingly sold as objects &ldquofrom Luristan.&rdquo Fragments or parts of one and the same object were sometimes sold separately and became dispersed among various collections. One such case concerns the quiver plaques in the Musée du Louvre (former David-Weill collection), and in the Royal Museums of Art and History, Brussels (former E. Graeffe collection). Recognized by Pierre Amiet as of the same style (Amiet, 1976, pp. 84-87, cat. 197), they are in fact part of one large quiver plaque (FIGURE 1), comparable in size and pattern to others whose provenance cannot be verified. The presence in many collections of single decorated cheek pieces of horse-bits instead of matching pairs also indicates that the breaking up of objects was common practice. At the same time, copies, forgeries, and pastiches were sold as genuine Luristan bronzes to meet the ever-increasing demand. Some of the pastiches were relatively naive. Idols were, for example, systematically mounted on bottle shaped supports with clothing pins (Godard, 1931, pl. LII-LVII FIGURE 2). It was a simple and easy way of presenting them but it took the evidence of excavated finds to disprove such a combination. Other pastiches were more sophisticated and elaborately deceitful. For example, a metal bowl, exhibited at the 1931 Burlington House exhibition, was mounted on a stand and decorated by adding to it parts of broken-up idols (FIGURE 3 Potratz, 1963, p.144, pl. XLIII Calmeyer, 1969, p. 138, fig. 145). Among the forgeries, one can distinguish between after-casts, genuine objects to which fake decorations were added to enhance their value, and modern made objects created in the &ldquoLuristan style.&rdquo When studying a fake decorated cheek-piece in the New York Metropolitan Museum of Art, Oscar White Muscarella was able to trace ten more in various collections and museums which suggests that eight after-casts were made from a set of two original cheek-pieces (Muscarella, 1982).

One of the first scholars to emphasize the extent of these problems was Potratz. He listed a series of bronzes in major museums and collections that he considered to be forgeries or pastiches (Potratz, 1963, pp. 131-45). In his opinion, anything with a unique character that deviated from the already known corpus of Luristan bronzes had to be treated suspiciously, an approach that led him to erroneously list some objects from other cultural areas as forgeries. Inspired by the approach of the Corpus Vasorum Antiquorum series of ancient Greek pottery, he proposed to start a Corpus aerum luristanensium, which would illustrate all Luristan bronzes in public and private collections (Potratz, 1963, pp. 145-47). His already cited studies on horse-bits and idols from Luristan depended largely on such a corpus as he had already started assembling on his own. A more complete and internationally organized corpus should in his mind have been the instrument to evaluate new arrivals available on the art market and thus &ldquoto close off the Luristan entity from alienation by the growing influx of forgeries&rdquo (&ldquo. den Gesamtkomplex der Luristania gegen die Verfremdung durch die sich häufende Flut der Falsifikate abzusichern.&rdquo Potratz, 1963, p. 147). Although his Corpus never materialized, the attention he had drawn to the presence of fakes and pastiches (FIGURE 2) in almost all Luristan collections, even those dating back to the 1930s, could from then on no longer be neglected or minimized. At the same time, however, it was clear that art historical studies alone could never completely resolve the issue, and analytical studies of the metal and its corrosion have since become important in establishing authenticity (on Luristan copies, forgeries and pastiches, see Muscarella, 1977, pp. 171-78, pl. XI-XIII 1988, p. 141 2000, pp. 81-119, 378-419 Calmeyer 1969, pp. 137-42, Abb. 145).

A new methodological approach was used by Peter Calmeyer just a few years later (Calmeyer, 1969). He selected only those bronzes that could be securely dated, either by inscriptions or by typological comparison with Mesopotamian and Iranian excavated finds. It allowed him to make a reliable chronological survey of bronzes dating from the third to the first millennium, placing them within their proper cultural context. In the main part of his book, the author discussed 53 types of objects, considering their date, geographical distribution and cultural origin. Separate chapters on forgeries and pastiches (&ldquoManipulierte Bronzen&rdquo), and inscribed bronzes completed his work. While his work went far beyond the scope of the Luristan bronzes, the drawback of his approach was that several groups of canonical Luristan bronzes (&ldquomaster of animals&rdquo type idols, whetstone handles, etc.) could not be discussed as there were none or insufficient datable comparisons available. Nevertheless, by dating specific groups like the spike butted axe heads, of which three from the Foroughi collection with 12th century royal inscriptions had been published only a few years before (Dossin, 1962 Ghirshman, 1962), he was able to define the chronological limits of the canonical Luristan style. Calmeyer&rsquos study was one of the first that could also make use of new data deriving from the Belgian excavation project directed by Louis Vanden Berghe. Within a few years, two more catalogues of large collections were published, one by Peter Roger Stuart Moorey on the bronzes in the Ashmolean Museum at Oxford (Moorey, 1971), and the other by Amiet on the private David-Weill collection (Amiet, 1976) of which 27 items were donated to the Louvre Museum as compensation for his work (Amiet, 1972 1976, p. xi). Both catalogues provided an elaborate survey of the complete range of bronzes as known from the art markets. They incorporated the growing information from excavations with the earlier object directed studies, and were able to provide clear distinctions between canonical Luristan bronzes of the Iron Age date, and general west Iranian, Elamite, and so-called Amlash (q.v.) or North Iranian bronzes. Both catalogues thus became essential works of reference for all subsequent publications on Iranian bronzes.

P. Amiet, Les Antiquités du Luristan. Collection David-Weill, Paris, 1976.

P. Calmeyer, Datierbare Bronzen aus Luristan und Kirmanshah, Berlin, 1969.

G. Dossin, &ldquoBronzes inscrits du Luristan de la collection Foroughi,&rdquo Iranica Antiqua II, 1962, pp. 149-64, pl. XIII-XXXIV.

R. Ghirshman, Iran, from the Earliest Times to the Islamic Conquest, Harmondsworth, U.K., 1954.

Idem, &ldquoA propos des bronzes du Luristan de la Collection Foroughi,&rdquo Iranica Antiqua II, 1962, p. 165-79.

Idem, Le Manuscrit R.G., Les Cimmériens et leurs Amazones, ed. Thérèse de Sonneville-David and Tania Ghirshman, Mémoire (éditions recherche sur les civilisations), 18, Paris, 1983.

A. Godard, Les Bronzes du Luristan, Ars Asiatica XVII, Paris, 1931.

Y. and A. Godard, Bronzes du Luristan, Collection E. Graeffe, The Hague, 1954.

E. Herzfeld, Iran in the Ancient East, London and New York, 1941.

Y. Maleki, &ldquoUne fouille en Luristan,&rdquo Iranica Antiqua 6, 1964, pp. 1-35, pl. I-XII.

P. R. S. Moorey, Catalogue of the Ancient Persian Bronzes in the Ashmolean Museum, Oxford, 1971.

Idem, &ldquoTowards a chronology for the &ldquoLuristan Bronzes,&rdquo Iran 9, 1971, p. 113-29, 9 fig.

Idem, Ancient Bronzes from Luristan, London, 1974.

O. W. Muscarella, &ldquoUnexcavated Objects and Ancient Near Eastern Art,&rdquo in Louis D. Levine and T. Cuyler Young, Jr. eds., Mountains and Lowlands: Essays in the Archaeology of Greater Mesopotamia, Bibliotheca Mesopotamica 7, 1977 pp. 153-207, pl. XI-XIV.

Idem, &ldquoAn aftercast of an ancient Iranian bronze,&rdquo Source, Notes in the History of Art 1:2, pp. 6-9.

Idem, Bronze and Iron, Ancient Near Eastern Artifacts in The Metropolitan Museum of Art, New York, 1988.

Idem, &ldquoMulti-piece iron swords from Luristan,&rdquo Archaeologia Iranica et Orientalis miscellanea in honorem Louis Vanden Berghe, ed. L. De Meyer and E. Haerinck, Ghent, 1989, pp. 349-66, 1 pl.

Idem, The Lie Became Great. The Forgery of Ancient Near Eastern Cultures, Groningen, 2000.

B. Overlaet, The Early Iron Age in the Pusht-i Kuh, Luristan, (Luristan Excavation Documents IV), Acta Iranica 40, Leuven, 2003.

E. Porada, &ldquoNomads and Luristan Bronzes: methods proposed for a classification of the bronzes,&rdquo in M. Mellnik ed., Dark Ages and Nomads c. 1000BC., Istanbul, 1964, p. 9-31, 3 fig., pl. I-VIII.

P. Potratz, &ldquoStangen-Aufsätze in der Luristankunst,&rdquo Jahrbuch für Kleinasiatische Forschung III-1, 1955, p. 19-42, pl. II-XV.

Idem, &ldquoDie Pferdegebisse des Zwischenstromländischen Raumes,&rdquo Archiv für Orientforschung XIV, 1941, pp. 1-39, 50 fig.

Idem, &ldquoDie Luristanischen Pferdegebisse,&rdquo Praehistorische Zeitschrift 32-33, 1941-1942, pp. 169-234, 84 fig.

Idem, &ldquoUber ein Corpus Aerum Luristanensium,&rdquo Iranica Antiqua 3/2, pp. 124-47, 4 fig., pl. XXIX-XLIV.

Idem, &ldquoDie Pferdetrensen des Alten Orients,&rdquo Analecta Orientalia 41, Rome, 1966.

Idem, Luristanbronzen: Die einstmalige Sammlung Friedrich Sarre, Berlin, Istanbul, 1968.

CH. H. Read, &ldquoTwo bronzes of Assyrian type,&rdquo Man 18, p. 1-3.

M. I. Rostovtzeff, Iranians and Greeks in South Russia, Oxford, 1922.

Cl. Schaeffer, Stratigraphie Comparée et Chronologie de l&rsquoAsie Occidentale, IIIe et IIe millénaires, London, 1948.

S. Smith, &ldquoTwo Luristan Bronzes from Southern Arabia,&rdquo in G. C. Miles, ed., Archaeologica Orientalia in Memoriam Ernst Herzfeld, Locust Valley, N.Y., 1952, pp. 203-207, 2 fig.

L. Speleers, &ldquoNos bronzes perses,&rdquo Bulletin des Musées Royaux d&rsquoArt et d&rsquoHistoire 3/2, 1931, pp. 56-63, fig. 26-27.

L. Vanden Berghe,B De Wulf and, E. Haerinck, Bibliographie analytique de l&rsquoarchéologie de l&rsquoIran ancien, Leiden, 1979.


Lorestān

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Lorestān, also spelled Luristan, geographic and historic region, western Iran. Its name means Land of the Lurs and it extends from the Iraqi frontier and Kermānshāh and separates the Khūzestān lowland from interior uplands.

Extensive mountains stretch northwest–southeast between the higher ranges are well-watered pockets with lush pastures. Oak forest covers the outer slopes, together with elm, maple, walnut, and almond trees. The Lurs are of aboriginal stock with strong Iranian and Arab admixtures, speak a Persian dialect, and are Shīʿite Muslims. Under the Pahlavis the Lurs were settled, and only a few retain their pastoral nomadism. Lorestān was inhabited by Iranian Indo-European peoples, including the Medes, c. 1000 bce . Cimmerians and Scythians intermittently ruled the region from about 700 to 625 bce . The Luristan Bronzes, noted for their eclectic array of Assyrian, Babylonian, and Iranian artistic motifs, date from this turbulent period. The bronzes were found mainly in tombs near Kermānshāh. Cyaxares, ruler of the Medes, drove out the Scythians in about 620 bce . Under Cyrus the Great, Lorestān was incorporated into the growing Achaemenid Empire in about 540 bce and successively was part of the Seleucid, Parthian, and Sāsānid dynasties.

Little Lorestān, the northern part, was governed by independent princes of the Khorshīdī dynasty, called atabegs, from 1155 to the beginning of the 17th century, when the last atabeg, Shāh Vardī Khān, was removed by the Ṣafavid ʿAbbās I the Great and government of the territory was given to the chief of a rival tribe, with the title of vālī his descendants retained the title.

The southern part of Lorestān, or Great Lorestān, was independent under the Faḍlawayh (Fazlaveye) atabegs from 1160 until 1424 its capital was Idaj, now only mounds and ruins at Malamir (modern Izeh).

Lorestān proper stretches between the Dez valley (used by the Trans-Iranian Railway) and the Upper Karkheh River and northward toward Nehāvend. Agriculture is the mainstay of the economy crops include rice, wheat, barley, cotton, oilseeds, sugar beets, vegetables, and fruits. Industries produce cement, sugar, processed foods, carded wool, and ginned cotton. Iron ore and molybdenum are mined. Roads and railways link Khorramābād with Borūjerd and Alīgūdarz.

This article was most recently revised and updated by Noah Tesch, Associate Editor.


Bronze Sheet from Luristan - History

Heritage Auctions Presents a 1943 Bronze Penny Bonanza

Published on October 21, 2020

Heritage Auctions Presents a 1943 Bronze Penny Bonanza

Despite these large quantities of regular issue coinage, a few rarities managed to be accidentally struck in tiny numbers and sneak out of the US Mint. 1943 "pennies" were meant to be struck in Steel, but just a few were accidentally created on bronze planchets, producing a rarity that has fascinated collectors ever since.

1943 was a strange year for the US Mint in several ways. First of all, Cents were struck in a silvery-colored Steel composition rather than the normal coppery-looking Bronze because of a shortage of industrial metals during World War II. Next, another change was made to the composition of Nickels because nickel was needed for the war effort as well. So-called "War Nickels" were created on 40% silver planchets to free up more nickel to be used for the Allied forces. Meanwhile, mintages of circulating coins were generally very high, with large numbers of small coins being produced in the 1940s overall. For example, nearly 1.1 billion Steel Cents were struck between the Philadelphia, Denver, and San Francisco Mints.

Despite these large quantities of regular issue coinage, a few rarities managed to be accidentally struck in tiny numbers and sneak out of the US Mint. Specifically, the famous rarity of 1943 is the Bronze Cent. 1943 "pennies" were meant to be struck in Steel, but just a few were accidentally created on bronze planchets, producing a rarity that has fascinated collectors ever since and sent many "roll hunters" on a search of rolls of pennies, looking for the ultimate numismatic prize.

Having just one 1943 Bronze Cent in an auction would be a major deal given that these are generally six figure coins. However, Heritage Auctions has a Bronze Cent bonanza going on due to the wonderful Bob Simpson collection, which contained more than one of these rare pieces!


Brief Early History of Brass

After the Copper (Chalcolithic) Age came the Bronze Age, followed later by the Iron Age. There was no 'Brass Age' because, for many years, it was not easy to make brass. Before the 18th century, zinc metal could not be made since it melts at 420ºC and boils at about 950ºC, below the temperature needed to reduce zinc oxide with charcoal. In the absence of native zinc it was necessary to make brass by mixing ground smithsonite ore (calamine) with copper and heating the mixture in a crucible. The heat was sufficient to reduce the ore to metallic state but not melt the copper. The vapor from the zinc permeated the copper to form brass, which could then be melted to give a uniform alloy.

Only in the last millennium has brass been appreciated as an engineering alloy. Initially, bronze was easier to make using native copper and tin and was ideal for the manufacture of utensils. Pre-dynastic Egyptians knew copper very well and in hieroglyphs copper was represented by the ankh symbol 'C' also used to denote eternal life, an early appreciation of the lifetime cost-effectiveness of copper and its alloys. While tin was readily available for the manufacture of bronze, brass was little used except where its golden color was required. The Greeks knew brass as 'oreichalcos', a brilliant and white copper.

Several Roman writers refer to brass, calling it 'Aurichalum.' It was used for the production of sesterces coins and many Romans also liked it especially for the production of golden colored helmets. They used grades containing from 11 to 28 per cent of zinc to obtain decorative colors for all types for ornamental jewelry. For the most ornate work the metal had to be very ductile and the composition preferred was 18%, nearly that of the 80/20 gilding metal still in demand.

As mentioned, in medieval times there was no source of pure zinc. When Swansea, in South Wales, was effectively the center of the world's copper industry, brass was made in Britain from calamine found in the Mendip hills in Somerset. China, Germany, Holland and Sweden had brass making industries with good reputations for quality. Brass was popular for church monuments, thin plates being let in to stone floors and inscribed to commemorate the dead. These usually contained 23-29% of zinc, frequently with small quantities of lead and tin as well. On occasions, some were recycled by being turned over and re-cut.

One of the principal industrial users of brass was the woolen trade, on which prosperity depended prior to the industrial revolution. In Shakespearean times, one company had a monopoly on the making of brass wire in England. This caused significant quantities to be smuggled in from mainland Europe. Later the pin trade became very important, about 15-20% of zinc was usual with low lead and tin to permit significant cold working to size. Because of its ease of manufacture, machining and corrosion resistance, brass also became the standard alloy from which were made all accurate instruments such as clocks, watches and navigational aids. The invention by Harrison of the chronometer in 1761 depended on the use of brass for the manufacture of an accurate timekeeper that won him a prize of ï¿䧨,000. This took much of the guesswork out of marine navigation and saved many lives. There are many examples of clocks from the 17th and 18th centuries still in good working order.

With the coming of the industrial revolution, the production of brass became even more important. In 1738, William Champion was able to take out a patent for the production of zinc by distillation from calamine and charcoal. Cast brass was hammered to make wrought plate in a water-powered 'battery'. Rods cut from the plate were then pulled through dies by hand to make the vital stock needed for pins for the textile weaving industry. Although the first rolling mills were installed in the 17th century, it was not until the mid-19th century that powerful rolling mills were generally introduced.

In America, one of the first recorded brass founders and fabricators is Joseph Jenks in Lynn, Mass from 1647 to 1679 with brass pins for wool making being a very important product. Despite legal restrictions, many others set up such works during the eighteenth century. (Schiffer, P. et al, The Brass Book, 1978, ISBN 0-916838-17-X).

With the invention of 60/40 brass by Muntz in 1832 it became possible to make cheap, hot workable brass plates. These supplanted the use of copper for the sheathing of wooden ships to prevent biofouling and worm attack.

With improvements in water communications, trade became easier and production could be sited near to fuel supplies and routes to facilitate central distribution round the country. In 1894, Alexander Dick invented the extrusion press that revolutionized the production of good quality low-cost rods. Subsequent developments in production technology have kept pace with customers' demands for better, consistent quality in products produced in large quantities.


Bronze

Bronze is an alloy that consists primarily of copper with the addition of other ingredients. In most cases the ingredient added is typically tin, but arsenic, phosphorus, aluminum, manganese, and silicon can also be used to produce different properties in the material. All of these ingredients produce an alloy much harder than copper alone.

Bronze is characterized by its dull-gold color. You can also tell the difference between bronze and brass because bronze will have faint rings on its surface.

Bronze Applications

Bronze is used in the construction of sculptures, musical instruments and medals, and in industrial applications such as bushings and bearings, where its low metal on metal friction is an advantage. Bronze also has nautical applications because of its resistance to corrosion.

Other Bronze Alloys

Phosphor Bronze (or Tin Bronze)

This alloy typically has a tin content ranging from 0.5% to 1.0%, and a phosphorous range of 0.01% to 0.35%. These alloys are notable for their toughness, strength, low coefficient of friction, high fatigue resistance, and fine grain. The tin content increases the corrosion resistance and tensile strength, while the phosphorous content increases the wear resistance and stiffness. Some typical end uses for this product would be electrical products, bellows, springs, washers, corrosion resistant equipment.

Aluminum Bronze

This has an aluminum content range of 6% – 12%, an iron content of 6% (max), and a nickel content of 6% (max). These combined additives provide increased strength, combined with excellent resistance to corrosion and wear. This material is commonly used in the manufacturing of marine hardware, sleeve bearings and pumps or valves that handle corrosive fluids.

Silicon Bronze

This is an alloy that can cover both brass and bronze (red silicon brasses and red silicon bronzes). They typically contain 20% zinc and 6% silicon. Red brass has high strength and corrosion resistance and is commonly used for valve stems. Red bronze is very similar but it has lower concentrations of zinc. It is commonly used in the manufacturing of pump and valve components.

Nickel Brass (or Nickel Silver)

This is an alloy that contains copper, nickel and zinc. The nickel gives the material an almost silver appearance. This material has moderate strength and fairly good corrosion resistance. This material is typically used to make musical instruments, food and beverage equipment, optical equipment, and other items where the aesthetics are an important factor.

Copper Nickel (or Cupronickel)

This is an alloy that can contain anywhere from 2% to 30% nickel. This material has a very high corrosion-resistance and has thermal stability. This material also exhibits a very high tolerance to corrosion cracking under stress and oxidation in a steam or moist air environment. Higher nickel content in this material will have improved corrosion resistance in seawater, and resistance to marine biological fouling. This material is typically used in making electronic products, marine equipment, valves, pumps and ship hulls.


The story of China - How the early Chinese made bronzes

Historian and presenter Michael Wood watches on as a modern bronze caster makes a replica of a Shang-style bronze bowl. At a state of the art science laboratory in Nanjing, Michael closely investigates a beautiful bronze bowl over 2,500 years old, trying to find out exactly how it was made, and how many different parts there are. We then get a ring-side seat as the bronze caster, in his modern workshop, tries to make an exact replica. He is very nervous, as he doesn't think he is skillful enough to make an exact copy. We see the mould being made and then molten bronze poured in. After cooling, the bowl is removed and all the different pieces - handles, plum blossom, gilded inlaid dragons - are assembled. It is a step by step guide to making a beautiful bronze bowl - and to appreciate the skills of an Ancient Civilisation.

Pupils could look carefully at the original bowl - what decorations can you see? What were bowls like this used for? How do we know who owned them? What do bowls like this tell us about Ancient Civilisations? This could be used to could compare the way Shang bowls were made with the way bronze swords were made in Bronze-Age Britain or how the Benin made their famous bronze masks. How similar, and how different, are these processes? Pupils could then consider what conclusions can be drawn about the Shang from seeing a replica bronze bowl being made?


Gauges are used to specify the thickness of a sheet metal. Gauges are neither standard nor metric and the values are independent of those measurement systems. A gauge conversion chart can be used to determine the actual thickness of sheet metal in inches or millimeters. For example, 18 gauge steel, according to a gauge conversion chart, is 0.0478 inch or 1.214 millimeter. The gauge number “18” holds no relevance to the actual measurements.

There are several different gauge systems used today, with specific gauge designations used for specific metal types. For example, in one gauge system, 18 gauge steel measures 0.0478 inches thick, but 18 gauge aluminum is 0.0403 inches thick. Because of the varying thicknesses, a gauge chart should be used to ensure the metal meets the required dimensions.


Watch the video: Ξυλοθήκη Μεσαία Φύλλα Χάλκινη (July 2022).


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  6. Walfrid

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