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Bronze is the most popular metal for cast metal sculptures; a cast bronze sculpture is often called simply a "bronze". 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.〔Savage, George, ‘’A Concise History of Bronzes’’, Frederick A. Praeger, Inc. Publishers, New York, 1968 p. 17〕 Their strength and ductility (lack of brittleness) is an advantage when figures in action are to be created, especially when compared to various ceramic or stone materials (such as marble sculpture). These qualities allow the creation of extended figures, as in ''Jeté'', or figures that have small cross sections in their support, such as the equestrian statue of ''Richard the Lionheart''.〔Caleb Hornbostel, ''Construction Materials: Types, Uses and Applications, Second Edition'' (New York: John Wiley & Sons, 1991) p. 175.〕 But the value of the bronze for uses other than making statues is disadvantageous to the preservation of sculptures; few large ancient bronzes have survived, as many were melted down to make weapons or ammunition in times of war or to create new sculptures commemorating the victors, while far more stone and ceramic works have come through the centuries, even if only in fragments. As recently as 2007 several life sized bronze sculptures by John Waddell were stolen, probably due to the value of the metal after the work has been melted.〔http://www.evelinenow.com/BeautyandtheBeastinCornvilleArizona.html〕 ==Material== There are many different bronze alloys, and the term is now tending to be regarded by museums as too imprecise, and replaced in descriptions by "copper alloy", especially for older objects. Typically modern bronze is 88% copper and 12% tin.〔Knapp, Brian. (1996) ''Copper, Silver and Gold''. Reed Library, Australia.〕 Alpha bronze consists of the alpha solid solution of tin in copper. Alpha bronze alloys of 4–5% tin are used to make coins and a number of mechanical applications. 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 with 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 may suggest that the candlestick was made from a hoard of old coins. The Benin Bronzes are really brass, and the 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 armour were hammered from mild bronze. On one definition, modern "statuary bronze" is 90% copper and 10% tin.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「bronze sculpture」の詳細全文を読む スポンサード リンク
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