Metal crafts

Japanese: 金属工芸 - きんぞくこうげい

Metalwork refers to crafts made primarily from metal, and the techniques for making them. It is also called metalwork or metalworking. Metallurgy, the art of extracting gold from gold ore, began in ancient civilizations such as ancient Egypt, Mesopotamia, India, and China around 4000 BC. Among the various metals, gold, silver, and copper were the first to be used in crafts, because they could be extracted and processed in their natural state. Gold, in particular, has always retained its shine and is easy to process, making it the most valuable material since ancient times. Metals were cut, hammered, and melted to be processed. During the melting stage, bronze, an alloy of copper and tin, appeared. This was the beginning of casting, and formed the civilization known as the Bronze Age. It is thought to have occurred around 3000 BC in the Orient and around 2000 BC in China. During the Greek and Roman periods, this copper and bronze culture slowly transitioned to the iron age, but some areas did not follow this process. During the Greek and Roman periods, it became easier to produce mercury and use it to extract gold, which led to the production of brass, an alloy of copper and zinc. In the Middle Ages, new mines and smelters were established, coal and water power were used in metallurgy, and in the 16th century, with the publication of Agricola's De re Metallica, metalworking ushered in the dawn of modern technology. The Industrial Revolution brought advances in machine technology and improved methods for extracting metals from ores, bringing about major changes in metalworking.

The main materials used in metal crafts are gold, silver, copper, tin, iron, and copper alloys such as bronze, cupro-nickel, and brass, and in recent years platinum, aluminum, and stainless steel have also become widely used.

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Metal craft techniques

Based on the technique, it can be broadly divided into three: casting, hammering, and engraving.

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Metal casting

Metals soften when heated, and melt when they reach a certain temperature. Taking advantage of this property, casting is done by pouring molten metal into a mold, allowing it to cool and solidify before removing it, which is called metal casting, or casting. Copper and copper alloys are the oldest, and casting is thought to have been done in Mesopotamia as early as 3000 BC. Cast iron does not melt or soften when heated after casting, and has the property of dissipating heat immediately, so it was used widely in Europe from the 15th century onwards for pots, pans, fireplaces and other products, and foundries were established all over the country. Casting molds include wax molds, solid molds, sand molds, and concave molds, as well as more recent methods such as electric casting, centrifugal casting, and the lost wax method.

(1) Wax casting: A hollow casting method that has been passed down from ancient times to the 19th century. The surface of the core mold is covered with a layer of wax made from beeswax mixed with rosin, in the same thickness as the piece to be made. A spout and an escape hole for the molten metal are made, and the entire surface is coated with casting clay, which is then hardened and dried. The entire mold is then heated, causing the wax to melt and flow out, and molten metal is poured into the space created. This method was used to make bronze vessels and gilt bronze Buddha statues.

(2) Sogata: A frame is filled with molding clay, which is then pressed or milled to create a concave mold. This is then fitted with a core to create the mold, and only the surface that comes into contact with the molten metal is baked and dried before being cast. This method is suitable for casting mirrors, kettles, temple bells, etc.

(3) Sand casting: A method in which a mold is made from sand suitable for casting, and the master model is pressed onto it for casting. Since the mold is not baked before casting, it is also called a green mold, and is used for casting coins, etc.

(4) Komaki: The original model of the work, such as a wood carving or plaster, is placed in a frame, covered with casting sand, and tamped down until there are no gaps. The entire mold is then turned over and the original model is removed. After that, a core is placed inside and the mold is formed. Most modern art casting is done using this method.

(5) Centrifugal casting: This is a method of precision casting that uses centrifugal force, and has become widely used in recent years.

(6) Electroforming The principle is the same as electroplating. A mold release agent is applied to the original, a thick layer of plating is applied, and then peeled off to create a negative mold that is the inverse of the original. By repeating the same process on this mold, an exact replica of the original can be made. Since the same product can be made many times, electroforming is often used for mass-produced reproductions.

(7) Lost wax casting: A model is made from easily sculpted wax, embedded in a casting ring, heated to make the wax flow out, and metal is cast into the space created. Since multiple identical pieces can be made at once, this method is suitable for mass production of decorative items.

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Metalworking

Also called forging or hammering. Taking advantage of the malleability and shrinkage of metal, metal is heated and softened, placed against a metal backing, struck with a hammer, and repeatedly tempered to form into a single sheet. Forging has been around since around 2000 BC, and blacksmiths have made many forged iron products. Blacksmiths have specialized in making armor, swords, keys and locks, and in 13th century Germany and France, they excelled in making door fittings and iron bars for churches and homes. As industrialization progressed in the 19th century, blacksmithing techniques gradually disappeared, and today most products are mass-produced in factories using pressing (embossing) and spinning (spatula-squeezing). There are two types of forging techniques: the striking technique, in which a single sheet of metal is hammered from both sides to create a three-dimensional shape or to make a pattern stand out, and the extrusion technique, in which a thin metal plate is pressed against a cast original model and struck from above to transfer the shape of the original model.

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Metalworking

A technique mainly used for decoration, in which patterns are carved, embedded, or embossed into metal surfaces using various sizes of chisels. There are various types of carving, such as kebori, which carves letters and lines, takanikibori, which creates a embossed pattern, and susukibori, which cuts out the pattern to create a see-through appearance.

Other decorative techniques include inlay (a technique in which different metals are fitted into a base of iron or bronze), plating (a type of plating; the lacquer leaf method, in which gold leaf is attached with lacquer, is one type of this), and cloisonné.

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history

In Egypt, beads and pins were already being made from gold and copper around 4000 BC, and during the Dynastic period, processing techniques developed to produce intricate pieces such as the famous gold coffin and gold mask of King Tutankhamun.

Gold, silver and copper were known from early times in Western Asia and Anatolia, and golden helmets, bowls, cups and ornaments made using the techniques of forging, hammering and engraving have been excavated from the royal tombs of Ur dating back to the early 3rd millennium BC. From the end of the Neolithic period, bronze began to be used for casting, and the Bronze Age culture arose in the eastern Mediterranean region as well as in Mesopotamia and Egypt. For example, many bronze tools were produced in Crete around 2100 BC.

In the Iranian region, nomadic peoples produced distinctive gold and silver utensils, clothing clasps, and bronze horse equipment, and their bird, animal, and hunting designs were passed down to the Sassanid Empire in Persia, and later influenced Islam, Byzantium, and medieval Europe, as well as China during the Tang Dynasty and Japan during the Nara period.

The Anatolia region of Asia Minor (Turkey) also produced a wealth of metalwork during the Bronze Age from the 3rd to 2nd millennium BC. Troy and Alaca Höyük are representative ruins of this period in Anatolia. Circular inlaid patterns can be seen on the stag and bull statues excavated at Alaca Höyük. After breaking away from Greek and Roman rule, the Ottoman Turks entered the era of Ottoman Turkey, and produced unique Ottoman art in the 15th and 16th centuries. Motifs such as geometric and arabesque designs were spread throughout Asia and Europe. The jeweled inlay work was spectacular, and the jeweled gold inlaid helmet at Topkapi Palace and the cover of Sultan Murad III's Diban Poetry Collection are said to be the pinnacle of metalwork technology at the time.

On the other hand, the Etruscans, who inherited metalworking techniques from Greece, developed elaborate gold filigree work and also excelled in bronzeware with embossed copper plates and silver inlays. Rome was particularly skilled in silverware, and produced many beautiful products from the various places under its rule.

Metal crafts made great strides from the Middle Ages to the early modern period. In the early Middle Ages, metal crafts from the East were introduced to the West through the medium of nomadic tribes who migrated westward from Iran and the Black Sea coast. The Merovingian and Carolingian dynasties made use of Celtic and Roman traditions in the production of precious metal products and clasps inlaid with precious stones, and this trend was carried over to the Romanesque and Gothic periods. In particular, with the spread of Christianity, elaborate metal products were produced as liturgical implements. Organized groups of craftsmen also emerged, with monastic workshops playing a major role in this, and these workshops were the main producers of accessories such as crowns, brooches, and clasps, as well as holy vessels such as chalices, Gospel bindings, and reliquary containers. In the 14th century, the clasps on clergy robes changed from the previous reliefs and cameos to gorgeous cloisonné decorations set on silver, which became popular among the aristocracy and wealthy citizens. In Italy, mainly in Florence, Rome and Venice, metalwork developed into a wider field than before, also linking with the field of sculpture.

The most famous goldsmith of the 16th century was Benvenuto Cellini. His works include the Saltcellar of Francis I (Kunsthistorisches Museum, Vienna), animal pendants, and engravings with precious stones and enamel. In addition to his autobiography, he also wrote a manual on goldsmithing techniques.

Around this time, pewter (a tin and lead alloy) appeared in addition to the metal materials used until then. Pewter is suitable for fine line engraving, openwork, and embossing, and household items such as plates, jugs, and candlesticks with concrete and abstract designs were actively produced. Pewter jugs often appear in the still life paintings of the 17th century Dutch painter Jan Steen.

In the second half of the 16th century, techniques such as goldsmithing, jewellery and cloisonné were integrated, artists formed strong artisan guilds and their workshops were often concentrated in particular cities, leading to the development of metalwork with regional characteristics. Wenzel Jamnitsa established a large workshop in Nuremberg and specialized in the production of decorative vessels, perfecting the three-dimensional high relief work created by hammering. Dutch metalsmiths excelled in hammering techniques and created three-dimensional works featuring standing figures and other ornaments. Parisian workshops played a leading role in European metalworking throughout the Baroque and Rococo periods, and their influence continues to this day.

Silverware became popular in the 18th century. Candlesticks, clocks, and cosmetics were made, and gilded bronze was widely used as decorative fittings for furniture. Small items such as boxes, vases, and small bottles were also given as gifts to royalty.

In the 19th century, the introduction of electroplating and presses led to the mass production of tools, and metal crafts became almost exclusively decorative and artistic items. In the 20th century, metal crafts also began to follow a trend toward functionalism and expressionism, as a reaction against the excessive, ornate decoration of Art Nouveau at the end of the previous century.

[Nao Tomobe]

China

Bronze artifacts from the Yin and Zhou dynasties (around 1500 BCE) show that extremely sophisticated casting techniques had already been developed at that time. They can be broadly divided into production tools, weapons, tableware, and musical instruments, all of which were used as symbols of authority by those in power during rituals, banquets, and ceremonial events. Animal motifs are common on Yin bronze artifacts, and unusually shaped tableware and weapons with a strong ritual character are decorated with exaggerated taotie and dragon designs of animals and monsters such as cows, sheep, tigers, and dragons. There are also geometric patterns such as spiral vortex designs and thunder patterns.

At the end of the Zhou dynasty, bronzeware became more suited to everyday life than ceremonial items, but the precise and strict design of the Yin dynasty was lost, and animal designs became simpler. Bronzeware during the Warring States and Han dynasties became more delicate, inlaid with gold and silver, and boasted splendor, while simple everyday items were also produced. Silverware and ironware also began to be produced during this period.

Mirrors from the Warring States and Qin periods were thin, and many had the Hanchi pattern (a design of several dragons twisting and intertwining) cast flat onto the backs of the mirror. In the Western Han period, however, square grid four gods mirrors, which featured the four gods in geometric patterns, and linked arc patterns appeared, while in the Later Han period, picture mirrors and divine beast mirrors depicting tales of immortals and their customs were seen.

The Sui and Tang dynasties were a time when China's influence extended widely into the Western Regions, and new styles of gold and silver ware such as hu bottles, eight-panel cups, and footed cups influenced by Western culture appeared, and some designs, such as grape designs, were introduced from Europe. Mirrors were also eight-flowered or eight-ridged, and ornate styles such as the sea animal and grape mirror and the Boya piquant mirror were born. Gold and silver ware were also inlaid, and intricate granular gold work can be seen among accessories. Cultural artifacts from the Sui and Tang dynasties were introduced to Japan, and the Shosoin Repository contains metal crafts that represent the sophistication of the Tang dynasty, such as silver plates.

Compared to the Tang dynasty, gold and silverware from the Song dynasty sought intellectual beauty, and from the Yuan dynasty onwards, high-profile engravings were used for sash ornaments etc. This tendency has been carried over to the complex and intricate style of Chinese metalwork from the Ming dynasty onwards.

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Korea

The metalware excavated at Lelang is valuable as it shows artistic tendencies of the Chinese Han dynasty, but the grave goods of Old Silla excavated from an ancient tomb near Gyeongju are relics with distinctive characteristics unique to Korea. The jeweled crowns and earrings made of pure gold retain a strong sense of the ancient Korean national color with their delicate design and craftsmanship. There are few relics from the period of Silla unification, but the temple bell at Bondeoksa Temple in Gyeongju is noteworthy as it shows a unique style known as the Korean bell. From the Goryeo period, in addition to bronze bells and various Buddhist implements that follow in the footsteps of the Silla bells, there are various bronze bells that imitate Chinese mirrors. A distinctive feature of Goryeo period metalwork is silver inlay, and several examples have been preserved in Japan, including the Kinzanji incense burner handed down from Horyuji Temple.

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Japan

Chinese and Korean metalworking, mining, and metallurgy techniques were introduced to Japan around 300 BC during the Yayoi period, and casting began domestically around 100 BC. However, masterpieces like the ancient Chinese bronzeware were not made, and casting was limited to small pieces such as simple-shaped swords and ornaments. In the latter part of the Yayoi period, bronze swords and bronze spears were made mainly in Kitakyushu, and the sandstone molds used to make these have been excavated, proving that casting took place in Japan. Around 100 AD, many bronze bells were made, with designs of flowing water, people, animals, and houses cast into the casting surface. These have been found over a wide area, mainly in the Kinai region, and were thought to have been cast using clay molds, but in recent years stone molds have been discovered and it is now believed that early bronze bells were made using stone molds.

In the following Kofun period, metalwork became extremely diverse. Grave goods found in the tombs include religious implements, personal ornaments, and horse equipment, which indicate the authority of the ruling class. In addition to bronze mirrors imported from China, there were also copies of Chinese mirrors and mirrors unique to Japan. Mirrors with straight and curved lines and a straight edge pattern, mirrors with house patterns that depict houses, and bell mirrors with bells attached to the edge of the mirror are unique to Japan. Personal ornaments include crowns, earrings, belt fittings, and bracelets, and show engraving techniques such as openwork carving in gold, silver, and gilt-bronze, fine line work, and hair carving. Some swords and horse equipment are decorated with silver inlay, and some have openwork carvings with dragon patterns and palmette patterns that are reminiscent of designs that were introduced from as far away as Greece. Among the armor, the short armor was made by hammering iron plates to create curved surfaces, and several of these plates were joined together and bound with rivets or leather, demonstrating the advanced forging techniques of the time.

During the Asuka period, Buddhism was introduced from Baekje, and many skilled craftsmen came to Japan. Construction of temples and Buddha statues was actively carried out, and metalworking techniques developed dramatically. The Joroku Buddha (606) at Asukadera Temple and the Shaka Triad (623) at Horyu-ji Temple were both made by Tori Busshi, and both were gold-plated using wax casting. The copper plate with a thousand Buddha figures on the back of the door of the Tamamushi Zushi at Horyu-ji Temple also shows the extrusion technique of forging. This technique was popular from the Hakuho period to the Nara period, and involves either striking the back of the copper plate with a model in the shape of a Buddha statue, as in an engraving, or placing a thin copper plate on top of a half-thick model and hammering it from above to create a relief-like effect. A masterpiece of metalworking from that time is the gilt-bronze openwork kanjoban (a kanjoban) at the Tokyo National Museum's Horyu-ji Treasure Gallery. Beneath the canopy hangs a long banner made of copper plates measuring over 5 meters in length, with openwork carvings of Buddhas, Bodhisattvas, heavenly beings, and palmettes.

The Nara period was the heyday of metalworking. The principal image of Todaiji Temple, the Seated Vairocana Buddha (commemorated in 754 at the time of its consecration), which was commissioned by Emperor Shomu, is a gigantic cast Buddha statue that sits 15 meters tall and weighs 250 tons. Although it has lost much of its original appearance due to two fires, the world map of the Lotus Treasury engraved on the lotus petals still speaks of the grandeur of the time. The octagonal lantern in front of the Great Buddha Hall of Todaiji Temple is a wax casting of the Bodhisattva Singing half-cast on the door of the fire house with a diagonal lattice pattern, and is a work of metalwork that exudes a sense of volume. The silver crown of the Acalanatha Kannon, the principal image of the Sangatsudo Hall at Todaiji Temple, is an ornate piece made of silver plate engraved with arabesque patterns and decorated with amber, crystal, and jade, demonstrating the high level of metalworking technology at the time. The Shosoin treasures also include a wide variety of metalwork items, including cast items such as mirrors, shakujo (a metal staff), incense burners with handles, and silver jars, as well as forged items such as incense burners and trays.

In the first year of the Wadou era under Emperor Genmei (708), copper was presented from Chichibu in Musashi Province, which led to the creation of Japan's first minted coins, known as the Wadou Kaichin. The gold coin Kaiki Shoho is also known, but after several types of coins were produced, issuance was stopped and instead large quantities of Chinese coins were imported and circulated, and full-scale minting of coins did not begin until the Edo period.

The late Heian period saw the production of many metalwork pieces that reflected the delicate and elegant tastes of the aristocracy of the time, as seen in the Enryakuji Temple's Hoso-ge Hair-carved Gilded Copper Sutra Box (1031) and the Chuson-ji Temple's Gilded Copper Garland (with Hoso-ge motifs carved in openwork and Karyobinga by hammering). During this period, mirrors changed from the Tang style to Japanese mirrors. The base of the mirror became thinner, and was decorated with motifs of flowers, butterflies, birds, and other motifs. Mishotai, which featured carved images of Buddha or deities on the surface of the mirror, also became popular as mirror images to be worshipped.

As Buddhism flourished, temple bells were also made in large numbers from the Nara period. Temple bells are made by rotating the prototype around the center of the axis and touching it to the casting sand to create a mold. This method is called the "Hikigata" method, and examples of this include the beautiful bell of Byodo-in Temple and the bell of Jingo-ji Temple (875), famous for its inscription.

Esoteric Buddhism had recently emerged in the Buddhist world, and when Saicho, Kukai and others traveled to China, they brought back many Buddhist altar implements along with their teachings. Many esoteric Buddhist altar implements were subsequently made in imitation of these.

The Kamakura period was a time when samurai families rose to prominence in place of aristocrats, and metalwork of this era focused on decorative metal fittings for weapons and armor. Engraving techniques can be seen in the red-threaded metal fittings with a bamboo tiger motif at Kasuga Taisha Shrine and Yoshitsune's gauntlets. In the Buddhist world, the production of stupas for enshrining relics became popular, and the gilt-bronze openwork stupa at Saidaiji Temple and the gilt-bronze Nosakusho Tower at Chofukuji Temple display the pinnacle of metalworking technology. Metalwork of this era had a dignified atmosphere, mirrors became thick, and realistic patterns and heavy Buddhist implements were preferred.

In the Muromachi period, there are many sword fittings worth seeing, such as the tsuba (guard), menuki (guard), kogai (hairpin), and kozuka (guard). The engraver Goto Yujo became the founder of the Goto family, and his descendants were active for 17 generations.

From the Kamakura to the Edo period, improvements were made to the tatara furnaces used to refine iron, making it possible to produce high-quality steel. As a result, cast iron products began to appear in large numbers, replacing bronze products, but the majority of their uses were rice cooking utensils such as pots and kettles, and agricultural tools such as hoes and shovels. However, with the popularity of the tea ceremony during the Muromachi period, kettles for the tea ceremony began to be cast. Famous examples are the Ashiya kettles at the mouth of the Onga River in Fukuoka Prefecture, Kyushu, and the Tenmyo kettles in Sano, Tochigi Prefecture. The Ashiya kettles have a smooth surface and an elegant cast pattern, while the Tenmyo kettles are characterized by their rough surface and interesting shape. The production of kettles also began in Kyoto, and kettle makers such as Nagoshi Zensei, Nishimura Donin, and Tsuji Yojiro emerged. Sword accessories were also developed, and during the successive generations of the Goto clan, Umeda Myoju left behind gorgeous and elegant sword tsuba works that applied openwork and inlay. In the Momoyama period, vast mansions and castles in the Shoin-zukuri style were built, and metalwork was applied to the architectural details such as pillar fittings, handles, and nail covers.

During the Edo period, swords became objects of appreciation, rather than of practical use, and accessories became more decorative. Metalwork in general tended to focus on peripheral techniques, and in the late Edo period, stationery items with embossed and openwork designs, which were popular among literati, were elaborately made using wax casting. Mirrors with handles appeared in the late 16th century and remained popular until the early Meiji period.

After the Meiji period, the various techniques that had been used up until that point were inherited and Western technology was also introduced, but there were major changes due to changes in lifestyle accompanying social change, and Japanese metalworking also began to be introduced at international expositions overseas. Metalworking artists such as Homma Takusai, Suzuki Chokichi, and Oshima Joun were active, while metal engravers such as Kano Natsuo, Unno Shomin, and Kagawa Katsuhiro were active, and metalsmiths such as Hirata Muneyuki were prominent. From the Meiji period through the Taisho and Showa periods, Tsuda Nobuo, Katori Hotsuma, Shimizu Nanzan, and Kitahara Senroku were particularly active. Artists were greatly inspired by the frequent art and craft exhibitions held after the Meiji period, and it is also important to note that techniques developed as the demand for metalworking increased.

[Katori Tadahiko]

"Japanese Art 39: Metalwork" by Kurata Kura and Nakano Masaki (1974, Shogakukan)

[Reference items] | Cloisonné | Inlay | Engraving

Source: Shogakukan Encyclopedia Nipponica About Encyclopedia Nipponica Information | Legend

Japanese:

金属をおもな素材として加工した工芸品、およびそれをつくる技術。金工、金属細工ともいう。金の鉱石から金をとる冶金(やきん)術が古代エジプト、メソポタミア、インド、中国といった古代文明が発達した地域に発生するのは紀元前4000年ごろからで、諸金属のうち金、銀、銅がもっとも早く工芸品として用いられたが、これは天然の状態でも採取加工が可能であったからである。とくに金は、つねに輝きを保ち、また加工しやすいこともあって、古来もっとも貴重な素材とされた。加工には金属を切ったりたたいたり溶かしたりした。この溶かす段階で銅と錫(すず)の合金、青銅(せいどう)が現れた。これが鋳造の始まりで、いわゆる青銅器時代といわれる文明を形成した。オリエントでは前3000年ごろ、中国では前2000年ごろと考えられる。ギリシア・ローマ時代にはこの銅と青銅の文化がゆっくり鉄の時代へ移っていくが、地域によってはこの過程を踏まない所もある。ギリシア・ローマ時代に水銀の製造とそれによる金の抽出が容易になり、銅と亜鉛の合金、真鍮(しんちゅう)が製造されるようになった。中世には新しい鉱山や溶錬場ができ、石炭や水力が冶金に使われ、16世紀にアグリコラの『デ・レ・メタリカ』が出て、金属工芸は近代技術の夜明けを迎える。産業革命は機械技術を進歩させ、鉱石から金属をとる方法も改善されて、金属工芸は大きく変化した。

　金属工芸のおもな材料は、金、銀、銅、錫、鉄のほか、銅合金の青銅、白銅、真鍮などがあり、近年はプラチナ、アルミニウム、ステンレス鋼なども広く用いられている。

［香取忠彦］

金属工芸の技法

その技法から鋳金(ちゅうきん)、鍛金(たんきん)、彫金(ちょうきん)の三つに大別することができる。

［香取忠彦］

鋳金

金属は加熱すると柔らかくなり、定温に達すると溶解する。この性質を利用して、溶けた金属を型の中に流し込んで冷却凝固してから取り出すのが鋳金で、鋳物(いもの)ともいう。銅または銅の合金はもっとも古く、前3000年にはメソポタミアで鋳造が行われていたと思われる。鋳鉄は、鋳造後は熱せられても溶けず柔らかくもならず、ただちに熱を発散する性質があるので、15世紀以後のヨーロッパで、鍋(なべ)や暖炉など広い範囲に使われ、各地に鋳造所ができた。鋳造の鋳型は蝋型(ろうがた)、惣型(そうがた)、砂型(すながた)、込型(こめがた)のほか、最近は電気鋳造、遠心鋳造、ロストワックス法などがある。

(1)蝋型　古代から19世紀まで受け継がれてきた中空鋳造法。心型の表面を、つくろうとする作品と同じ厚さの蜜蝋(みつろう)に松脂(まつやに)を混ぜた蝋で覆う。湯口や湯（溶かした金属を湯という）の逃げ口をつくり、全面を鋳型土（粘土）で塗り固め乾かす。次にこの鋳型全体を熱すると、蝋は溶けて流れ出し、そのあとにできた空間に、溶かした金属を注入する方法で、青銅器や金銅仏の製作に用いられた。

(2)惣型　枠の中に鋳型土を詰め、これを型押しや型挽(ひ)きによって凹形の鋳型をつくり、この中子(なかご)をあわせて鋳型とし、溶けた金属の当たる面だけ焼いて乾燥させ鋳造する方法で、鏡、釜(かま)、梵鐘(ぼんしょう)などの鋳造に適している。

(3)砂型　鋳造に適した砂で鋳型をつくり、その上に原型を押して鋳造する方法。鋳型を焼かずに鋳造するところから生(なま)型ともいい、銭貨の鋳造などに用いられる。

(4)込型　木彫や石膏(せっこう)などの作品原型を枠の中に置き、鋳物砂をかぶせて、すきまなく突き固め、鋳型全体を反転して原型を引き抜く。そのあとに中子を収め鋳型とする法。現在の美術鋳物はほとんどこの手法による。

(5)遠心鋳造　遠心力を利用して精密な鋳造を行うもので、近年盛んに用いられている。

(6)電気鋳造　電気めっきと原理は同じで、原型に離型剤を塗り、めっきを厚くかぶせてはがすと、原型と逆の雌型ができる。その型に同じ方法を繰り返すことによって原型と同じものをつくる。同じものが何度もできるので、マスプロの複製品には電気鋳造が多い。

(7)ロストワックス法　造形が容易なワックスで原型をつくり、鋳造リングに埋め込み、加熱してワックスを流し出してできた空間に金属を鋳込む法。一度に何個も同じものがつくれるので、装飾品などの量産の製造に向いている。

［香取忠彦］

鍛金

鍛造、打物(うちもの)ともいう。金属の展延性、収縮性を利用して、加熱し柔らかくなった金属を当て金に当て、金槌(かなづち)で打ち、なましを繰り返して1枚の板で成型する。鍛金は前2000年ごろからあり、鍛冶(かじ)屋によって多くの鍛鉄品がつくられてきた。甲冑(かっちゅう)、刀剣、鍵(かぎ)と錠前など、鍛冶屋の専門分化が進み、13世紀のドイツやフランスでは教会や住宅の扉金具や鉄格子に優れたものがある。19世紀に工業化が進むと鍛冶屋の技術も徐々に消滅し、現在では工場の大量生産によるプレス（型押し）、スピニング（へら絞り）がほとんどである。鍛金の技法としては、1枚の金属を表裏から槌で打ち出して立体的な形をつくったり、文様を浮き出たせる打出し技法と、鋳造原型の上に薄い金属板を押し当て、上からたたいて原型の形を転写する押出し技法とがある。

［香取忠彦］

彫金

おもに加飾に用いられる技法で、大小各種の鏨(たがね)で金属面に模様を彫ったり、埋め込み、浮彫りをする技法。文字や線を彫る毛彫り、文様を浮彫り風に表す高肉彫り、切り透かして文様を表す透(すかし)彫りなどがある。

　その他の加飾技法には、象眼(ぞうがん)（鉄や青銅の素地に異なった金属をはめ込んでゆく技法）、鍍金(ときん)（いわゆるめっき加工。漆(うるし)で金箔(きんぱく)を付着させる漆箔(しっぱく)法もこの一種）、七宝(しっぽう)などがある。

［香取忠彦］

歴史

エジプトでは前4000年ごろすでに金と銅でビーズとピンがつくられ、王朝時代には加工技術も発達して、有名なツタンカーメン王の金棺や黄金のマスクのような精巧な作品が生まれた。

　西アジアやアナトリアでも、早くから金、銀、銅が知られ、前三千年紀初めのウルの王墓からは、鍛金、鎚起(ついき)、彫金の技法を生かした金の兜(かぶと)や、鉢、杯、装身具が発掘されている。新石器時代の末ごろから青銅が鋳造に使用されるようになり、メソポタミア、エジプトに加えて、地中海東部地域でも青銅器文化が興った。たとえば、クレタ島では前2100年ごろに多くの青銅器がつくられている。

　イラン地方では、遊牧民族による特色ある金銀器や衣服の留金(とめがね)、青銅の馬具がつくられたが、その鳥獣文や狩猟文はペルシアのササン朝に受け継がれ、後のイスラム、ビザンティン、中世ヨーロッパ、さらに唐代の中国、奈良時代の日本にも影響を及ぼした。

　小アジアのアナトリア地方（トルコ）でも前三千年紀から前二千年紀にわたる青銅器時代に、豊富な金工品を生み出した。トロイとアラジャ・ホユックはアナトリアのこの時代を代表する遺跡である。アラジャ・ホユック出土の雄鹿(おじか)、雄牛像には円形の象眼による模様がみられる。ギリシア、ローマの支配から脱して、オスマン・トルコの時代を迎え、15、16世紀に特異なオスマン美術を生み出した。その幾何学文様や唐草文様などのモチーフはアジアやヨーロッパに伝わった。宝石をちりばめた象眼細工は目を見張るものがあり、トプカプ宮殿の宝石金象眼兜や、スルタン・ムラト3世の『ディーバーン詩集』の表紙などは当時の金工技術の極致といえる。

　一方、ギリシアから金工技術を受け継いだエトルリアでは精巧な金線細工が発達し、銅板の打出しや銀象眼をもつ青銅器にも優れていた。ローマはとくに銀器に優れ、支配下の各地から多くの美しい製品を生んでいる。

　中世から近世にかけて金属工芸は飛躍的な発展を遂げた。中世の初期には、イランや黒海沿岸から西方に移動した遊牧民族などを媒介として、東方の金属工芸が西方に伝えられた。メロビングおよびカロリングの2王朝は、貴石を象眼した貴金属製品や留金などにケルトやローマの伝統を生かし、この傾向はロマネスク、ゴシックの時代に受け継がれてゆく。とくにキリスト教の普及とともに、典礼具として精巧な金属製品がつくられたことが注目される。組織化された職人の集団も生まれてきたが、これには修道院工房が大きな役割を果たし、王冠、ブローチ、留金などの装身具、聖杯、福音書(ふくいんしょ)装丁板、聖遺物容器などの聖器具類がこれらの工房を中心に製作された。14世紀、聖職者の法衣につける留金は、それまでの浮彫りやカメオから銀台に華麗な七宝装飾のものにかわり、貴族階級や富裕な市民にも愛用された。イタリアではフィレンツェ、ローマ、ベネチアを中心に、彫刻の分野とも結び付いて、金工は従来よりさらに広い範囲に発展した。

　16世紀におけるもっとも有名な金細工師はベンベヌート・チェッリーニである。その作品には『フランソア1世の塩入れ』（ウィーン美術史博物館）のほか、動物文のペンダント、宝石やエナメル金彩の彫金などがある。彼は自叙伝のほかに金細工に関する技法書も書いている。

　このころ、それまでの金属素材に加えてピューター（白鉛。錫と鉛の合金）が登場した。ピューターは細い線彫りや透(すかし)細工、打出しなどに適しており、具象や抽象の文様の皿、水差し、燭台(しょくだい)などの家庭用品が盛んにつくられた。17世紀オランダの画家ヤン・ステーンの静物画にもピューターの水差しがしばしば登場する。

　16世紀後半に金細工、宝石細工、七宝(しっぽう)などの技術が総合され、作家たちは強固な職人組合をつくり、彼らの工房はしばしば特定の都市に集中したので、地方的に特色ある金属工芸が発達した。ウェンツェル・ヤムニッツァはニュルンベルクに大工房を設立し、装飾的な容器の製作を得意とし、打出しによる立体感ある高浮彫り細工を完成した。オランダの金工たちは鍛金の技法に長じ、立像などを配した立体的な作品をつくった。パリの工房はバロック、ロココを通じてヨーロッパの金属工芸の主導的役割を果たし、その影響は今日に及んでいる。

　18世紀には銀器が人気を集める。燭台、時計、化粧道具などがつくられたほか、家具の装飾金具として鍍金ブロンズが多用された。また、箱、壺(つぼ)、小瓶などの小物は王侯の贈答品にも使われた。

　19世紀になると、電気めっきや圧搾機の導入で道具類が大量生産されるようになり、金属工芸品は装飾品、工芸品にほとんど限られるようになる。そして20世紀には、前世紀末のアール・ヌーボーの華麗な装飾過多に対する反発から、金属工芸も機能主義的、表現主義的傾向をたどるようになっていった。

［友部　直］

中国

殷周(いんしゅう)時代（前1500ころ）の青銅器遺品によって、当時すでにきわめて精巧な鋳造技術が発達していたことがわかる。生産工具、武器、飲食器、楽器などに大別されるが、いずれも祭祀(さいし)、宴会、儀礼行事に権力者たちの権威の象徴として用いられた。殷代青銅器は動物文が一般的で、祭器的性格の強い異形の飲食器や武具は、牛、羊、虎(とら)、竜など動物や怪獣を誇張したデザインの饕餮(とうてつ)文、虺竜(きりゅう)文などで飾られている。このほか渦巻状の円渦文、雷文などの幾何学文様もある。

　周代末になると、青銅器は儀礼的なものより実生活に即したものが多くなるが、殷代の精巧厳格さは失われ、動物図案も簡略化してくる。戦国・漢代の銅器は繊細さを増し、金銀象眼したり、鍍金して華麗さを誇り、その一方で簡素な日常雑器もつくられている。またこの時代に銀器、鉄器もつくられるようになった。

　戦国・秦(しん)時代の鏡は薄手で、その鏡背に蟠螭(はんち)文（数匹の竜が身をくねらせて絡み合う文様）を平面的に鋳出したものがみられるが、前漢時代になると、幾何学文様に四神を配した方格規矩(きく)四神鏡や連弧文が現れ、後漢(ごかん)には神仙物語や風俗を表した画像鏡や神獣(しんじゅう)鏡がみられる。

　隋(ずい)唐時代は、中国の勢力が広く西域(せいいき)に及んだ時期で、西域文化の影響を受けた胡瓶(こへい)、八曲杯、脚杯といった新形式の金銀器が現れ、文様も葡萄(ぶどう)文などヨーロッパの産物を伝えたものがある。鏡も八花形、八稜(りょう)形で、海獣葡萄鏡や伯牙弾琴(はくがだんきん)鏡などの華麗な様式が生まれた。金銀器も象眼を施したり、装身具のなかには細密な粒金細工もみられる。隋唐の文物はわが国に伝わり、正倉院には銀盤など唐代の粋を示す金属工芸が伝わっている。

　宋(そう)代の金銀器は唐代に比べ理知的な美を求め、元(げん)以後は帯飾りなどに高肉彫りが使われている。こうした傾向は明(みん)代以後の複雑・細密な中国金工の作風に受け継がれている。

［香取忠彦］

朝鮮

楽浪(らくろう)出土の金属器は中国漢代の美術的傾向を示すものとして貴重であるが、朝鮮独自の特色ある遺品としては、慶州付近の古墳出土の古新羅(しらぎ)の副葬品がある。純金製宝冠や耳飾りは、繊細な意匠と技巧で古代朝鮮の民族色を色濃く残している。新羅統一時代の遺品は少ないが、慶州奉徳寺の梵鐘は朝鮮鐘と称される独自の様式を示すものとして注目される。高麗(こうらい)時代にはこの新羅鐘の流れをくむ銅鐘や種々の仏具のほか、中国鏡を模した各種の銅鐘がある。高麗時代の金工の特色は銀象眼で、法隆寺伝来の金山寺香炉ほかいくつかの遺例が日本にも伝わっている。

［香取忠彦］

日本

中国・朝鮮の金工、採鉱、冶金(やきん)技術が日本に渡来したのは弥生(やよい)時代、前300年ごろで、前100年ごろには国内でも鋳造が始まった。しかし中国古代青銅器のような大作はつくられず、形状の単純な刀剣類や装飾品など小型の作品に限られていた。弥生時代の後期になると、北九州を中心に銅剣、銅鉾(どうほこ)がつくられ、これらをつくった砂岩の鋳型も出土しているところから、日本で鋳造が行われたことがわかる。紀元後100年ごろには鋳肌に流水文、人物や動物や家屋などの文様を鋳出した銅鐸(どうたく)が多数つくられた。畿内(きない)を中心に出土地も広範囲に及び、土型による鋳造と考えられていたが、近年石鋳型が発見され、初期の銅鐸は石型によったものと考えられている。

　次の古墳時代になると、金工はきわめて多彩になる。墳墓の副葬品には支配階級の権威を示す宗教用具、装身具、馬具がみられる。銅鏡は中国からの舶載品のほかに、中国鏡を模したものや、日本独自の鏡もつくられた。直線と曲線で構成された直孤文鏡、家屋を文様化した家屋文鏡、鏡の周辺に鈴を取り付けた鈴鏡(れいきょう)は日本独自のものである。装身具には冠、耳飾り、帯金具、釧(くしろ)などがあり、金、銀、金銅の透(すかし)彫り、細線細工、毛彫りなどの彫金技術がみられる。大刀(たち)や馬具のなかには銀象眼を施したものや竜文、遠くギリシアからの伝播(でんぱ)を思わせるパルメット文などを透彫りにしたものがある。甲冑のうち短甲は鉄板で槌出し曲面をつくり、これらの板を何枚もあわせ、鋲留(びょうどめ)または革綴(かわとじ)してあり、当時の進んだ鍛造技術を示している。

　飛鳥(あすか)時代に百済(くだら)から仏教が伝来し、熟練した工人も多数来朝して、造寺・造仏が盛んに行われ、金工技術は飛躍的に発展した。飛鳥寺の丈六仏（606）、法隆寺釈迦(しゃか)三尊（623）は止利(とり)仏師の作であり、いずれも蝋型鋳造で金めっきを施してある。また、法隆寺の玉虫厨子(たまむしずし)の扉背面の千仏銅板には鍛金の押出し技法がみられる。これは白鳳(はくほう)から奈良時代にかけて流行した技法で、刻印のように銅板の裏から仏像の形をした原型で打つか、半肉の原型の上に薄い銅板をのせて上からたたいて浮彫り風に肉づけしたものである。当時の彫金の傑作には東京国立博物館法隆寺宝物館の金銅透彫灌頂幡(かんじょうばん)がある。天蓋(てんがい)の下に銅板を組み合わせた長さ5メートル余の長幡(ちょうばん)を下げ、仏、菩薩(ぼさつ)、天人、パルメット文を透彫りにしてある。

　奈良時代は金工の最盛期であった。聖武(しょうむ)天皇の発願になる東大寺の本尊盧舎那仏坐像(るしゃなぶつざぞう)（754開眼(かいげん)供養）は座高15メートル、重さ250トンの巨大な鋳物仏像で、二度の火災で当初のおもかげを失っているとはいえ、蓮弁(れんべん)に刻まれた蓮華蔵(れんげぞう)世界図は当時の壮大な趣(おもむき)をいまに物語っている。東大寺大仏殿前の八角灯籠(とうろう)は、斜格子地文透(じもんすかし)の火舎(ほや)の扉に音声(おんじょう)菩薩を半肉に鋳出した蝋型鋳物で、量感あふれる金工作品である。東大寺三月堂本尊の不空羂索(ふくうけんじゃく)観音の銀製宝冠は、唐草文を透彫りした銀板に琥珀(こはく)、水晶、玉(ぎょく)を飾った華麗なもので、当時の金工技術の高さを示している。正倉院宝物にも、鏡、錫杖(しゃくじょう)、柄香炉(えごうろ)、銀壺(ぎんこ)などの鋳造品、薫炉(くんろ)、盤(ばん)などの鍛造品と多種多彩な金工品がある。

　元明(げんめい)天皇の和銅(わどう)元年（708）に武蔵(むさし)国秩父(ちちぶ)から銅が献上されたのがきっかけで、和銅開珎(わどうかいちん)とよばれる日本最初の鋳銭がつくられた。金貨の開基勝宝(かいきしょうほう)も知られているが、その後何種かの銭製造ののち発行が停止され、かわって中国銭が多量に輸入されて流通し、本格的な銭貨の鋳造は江戸時代をまつこととなる。

　平安後期は延暦寺(えんりゃくじ)の宝相華(ほうそうげ)毛彫金銅経箱（1031）や中尊寺の金銅華鬘(けまん)（透彫りで宝相華を表し、打出しによる迦陵頻伽(かりょうびんが)を付す）にみられるように、当時の貴族の繊細優美な好みを反映した金工が多い。この時代、鏡は唐式から和鏡に変化した。鏡胎は薄くなり、草花、蝶(ちょう)、鳥などの文様を配している。また鏡の表面に御正体(みしょうたい)といって、仏像、神像を毛彫りで表し、礼拝の対象とした鏡像も流行した。

　仏教の隆盛に伴って梵鐘も奈良時代から多くつくられた。梵鐘は中心部を軸として鋳物砂に接触して原型を回転させ鋳型をつくる。これを引き型法といい、姿の美しい平等院の梵鐘、銘文で名高い神護寺の梵鐘（875）などが知られている。

　仏教界では新しく密教がおこり、最澄(さいちょう)、空海(くうかい)らが入唐(にっとう)して宗義とともに多数の仏具を請来したが、以後それに倣って多くの密教仏具がつくられた。

　鎌倉時代は貴族にかわって武家が台頭した時代で、この時代の金工は武具、甲冑類の飾り金具に集中する。春日(かすが)大社の赤糸威(あかいとおどし)の竹虎(たけとら)文様金物や義経籠手(こて)などに彫金技法がみられる。仏教界では舎利(しゃり)奉安のための舎利塔の製作が盛んに行われ、西大寺の金銅透彫舎利塔、長福寺の金銅能作生(のうさっしょう)塔など金工技術の粋を示している。この時代の金工は重厚な趣(おもむき)をもち、鏡も厚手となり、文様も写実的で仏具も重厚なものが好まれた。

　室町時代には鐔(つば)や目貫(めぬき)、笄(こうがい)、小柄(こづか)など刀装具にみるべきものが多い。彫金家後藤祐乗(ゆうじょう)は後藤家の祖となり、子孫は17代にわたって活躍した。

　鎌倉時代から江戸時代にかけて鉄の精錬に使う炉「たたら」が改良され、良品質の鉄鋼生産が可能になった。こうして青銅製品にかわって鋳鉄製品が多く現れるようになるが、用途の大部分は鍋(なべ)、釜(かま)などの炊飯用品と鋤(すき)や鍬(くわ)などの農耕具であった。しかし、室町期に流行した茶の湯によって、茶の湯釜が鋳造されるようになった。九州福岡県の遠賀(おんが)川河口の芦屋(あしや)釜、栃木県佐野の天明(てんみょう)釜が有名。芦屋釜は地膚(じはだ)表面が滑らかで鋳出文様に風雅な趣があり、天明釜は荒々しい地膚と形のおもしろさに特徴がある。京都でも釜の製作が始まり、名越善正(なごしぜんせい)、西村道仁(どうにん)、辻与次郎(つじよじろう)などの釜師が輩出した。刀剣小道具も発達し、前述の後藤家の各代、刀の鐔では埋忠明寿(うめただみょうじゅ)が透しや象眼を応用した華やかで気品の高い作品を残している。また桃山時代には書院造の広大な邸宅や城郭が造営され、柱金具、引手、釘隠(くぎかくし)など、建築の細部に金工が施された。

　江戸時代には、刀剣は実用を離れた賞玩(しょうがん)品となり、小道具類は装飾的傾向を強めた。金工全般に末梢(まっしょう)的な技巧にとらわれがちで、江戸後期には文人趣味の絵文様を浮彫り、透彫りにした文房具類が蝋型鋳物で精巧につくられた。鏡は16世紀後半に柄鏡(えかがみ)が出現して、以後明治初期まで流行した。

　明治以後は、それまでの各種技法を継承し、西洋の技術も導入されたが、社会的変革に伴う生活様式の推移により大きく変化し、また海外の万国博覧会などにも日本の金工が紹介されるようになった。鋳金家として本間琢斎(たくさい)、鈴木長吉、大島如雲(じょうん)、彫金家として加納夏雄(かのうなつお)、海野勝珉(うんのしょうみん)、香川勝広、鍛金家として平田宗幸らが活躍した。明治から大正、昭和にかけては津田信夫(のぶお)、香取秀真(かとりほつま)、清水南山、北原千鹿(せんろく)らの活躍が目だつ。明治以後しばしば開催された美術工芸展覧会によって作家は大きな刺激を受け、一方、金工の需要が拡大するに伴って技術を発展させたことも見逃せない。

［香取忠彦］

『蔵田蔵・中野政樹著『日本の美術39　金工』（1974・小学館）』

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出典　小学館　日本大百科全書(ニッポニカ)日本大百科全書(ニッポニカ)について　情報 | 凡例

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