Metalwork

Metalwork, in the fine arts, objects of artistic, decorative, and utilitarian value made of one or more kinds of metal—from precious to base—fashioned by either casting, hammering, or joining or a combination of these techniques.

ORIGINS OF METALWORK

Metals have been used throughout recorded history for fine and decorative art. By the 1st century ad the metals in prime use today—iron, copper, tin, lead, gold, and silver—already had a long development that had begun some 10,000 years earlier with the working of copper. The distinction between precious metals (gold, silver, and—since the 18th century—platinum) and base metals (iron, copper, tin, and lead) dates from the ancient civilizations of the Middle East and prehistoric Europe. Gold and silver, sacred to worshipers of the sun and the moon, were at first reserved for ritual religious use, temple objects, and the jewelry and ceremonial accoutrements of semisacred figures such as the early Egyptian pharaohs, the Middle Eastern priest-kings, and the tribal chieftains of Europe from Spain to the Caucasus. As these rare materials became more plentiful, they proclaimed the status of a wider group, the elite in each society—its nobility and great warriors. The use of gold and silver was extended to personal adornment, to personal belongings, such as eating and drinking utensils, weapons and equipment, and even to such furnishings as mirrors, lighting stands, chairs, and beds. Gold and silver gradually acquired a quantitative value, which was ultimately expressed in the first coins, stamped gold and silver disks issued by the Lydians in Asia Minor during the early 7th century bc. The notion of coinage soon spread throughout the Middle East and into Greece, and ever since that time coins have retained the notion of beauty as well as value. The base metals iron and bronze were appreciated for their strength, especially for weapons and tools; copper, tin, and lead came to be used mainly for their utility or durability—for cooking, for storage, or for strengthening wooden constructions of many kinds. The particular property of metals—that they can be mixed or alloyed in various combinations and proportions to make better materials for particular purposes—was understood in the ancient world. Copper and tin produced bronze; lead and tin produced pewter. This property has been exploited with ingenuity and increasing scientific knowledge in the past 2000 years; thus, while the designations iron, copper, lead, silver, and gold are still commonly used, nearly every metallic product is, in fact, a highly complex and carefully formulated alloy. For the purposes of the fine and decorative arts, however, metals have been used either in their simple state or in uncomplicated alloys.

CHARACTERISTICS OF METALWORK

All metals share certain characteristics: a uniform smooth complexion;.. great strength and tenacity, but also easily worked surfaces; and malleability (their capacity to assume any desired shape). This inherent malleability of metals is exploited by pressure in its solid state or by molding when it is liquefied by heat. In addition, metals were the first reusable materials known (unlike stone, shell, or wood), since broken or obsolete metal objects can be melted down and the substance reused. This relative permanence came to be appreciated after the discovery of smelting in about the middle of the 5th millennium bc.

TECHNIQUES OF METALWORK

The techniques of working metal developed very slowly and for long only in connection with the progress of metallurgy itself—the mining of a mass of metal from the earth. Scholarly opinion now holds that the first steps were taken after the adoption of settled ways of life—represented by agriculture and stock breeding—in northeastern Iran, the first area in which this occurred. In this area were native copper, metal-bearing rocks, malachite, and abundant timber, which allowed a steady progress of discoveries to be made. The Iranians learned the essentials of metalworking by using native copper; variations of the techniques were applied to other metals as they were recognized. A diffusionist theory is now generally accepted: The techniques were developed in northeastern Iran, but the products, and possibly also the producers, gradually were carried by trade and emigration to other areas. They went to the valley civilizations of Mesopotamia, across western Persia and through the east Mediterranean littoral to Egypt, across North Africa, and on into Spain. A second route lay from western Iran into Anatolia and then across the Hellespont to Europe. This diffusion began in about the 5th millennium bc and was continued for over 2000 years.

Early Techniques

The earliest metalworking was of copper, perhaps as early as the 11th millennium, using small nuggets of native copper picked up in streams or from the ground. These nuggets were presumably at first considered a special kind of attractively colored stone, and by grinding and beating—methods already used for working stones, flints, and obsidian—they could be shaped into ornaments.

Annealing

The next step was the discovery, about 5000 bc, that these special stones could be worked on with repeated hammering if the mass was heated to a full red color and cooled from time to time, and that this kept the metal soft and workable. Ordinary wood fires produced sufficient heat for this process, called annealing. Repeated hammering without annealing will cause the metal to become too hard and brittle, with resultant jagged cracks.

Smelting

The next discovery came after the development of the closed two-chamber pottery kiln, which produced a far greater heat than the open fires adequate for the earlier low-fired pottery. This took place probably before 4000 bc and led, after some 500 years or so, to the smelting first of small pieces of native copper, malachite (which under certain conditions will render into copper), and finally large amounts of copper ores, in furnaces that initially resembled the two-chamber pottery kilns. It was not until copper ores were smelted that any significant increase in the supply of copper and copper products could take place.

Alloys

Early Bronze Disk This disk with the head of Acheloos, an Etruscan river god, was made of bronze, an alloy of copper and tin, sometime in the early 5th century bc. It comes from the necropolis of Monte Quaglieri in Tarquinia. Alloys are made by smelting two different metals together.

Knowledge of smelting ultimately led to knowledge of mixing different ores together in the smelting process to produce simple alloys. This followed an intermediate period, about 3000 bc, when compound ores—rocks bearing one or two visibly different metallic particles—were observed to produce a superior metal. Copper produced by smelting continued to be shaped at first into small tools and ornaments by the grinding and beating methods long in use for working native copper. Weapons and tools dating to the late Predynastic period in Egypt (around 3000 bc) have been found, however, that were indubitably cast from smelted copper; at Ur of the Chaldees in Mesopotamia, in the royal graves of the 1st Dynasty (c. 3100-2907 bc) a profusion of beautifully worked objects in gold, silver, electrum (a natural alloy of gold and silver), copper, and even primitive bronze has been excavated, many made both by open-mold and lost-wax methods of casting.

Application of Techniques

By 2500 bc, at the least, all the main techniques for working metals had been very slowly pioneered in the treatment of copper over the preceding 3000 years. By that time these techniques were already being applied to other metals, such as silver, gold, and natural alloys of electrum and bronze. Techniques used for shaping were hot and cold forging or beating, which developed into hammering and raising techniques, using smooth hematite hammers; annealing; grinding, which led to the polishing and fine abrading used in the production of mirrors; piecing flat sheets of metal together with lapped seams or rivets and subsequently with solders; and casting. After the discovery of smelting, battering was used to flatten the cakes of metal into sheets; some form of battery continued to be necessary until the invention, in the late 17th century, of the rolling mill in which sheet metal was produced by mechanical means.

Joining, beating, annealing, raising, and casting were and remain the artistic methods used for shaping metals, although other methods, such as spinning, have been introduced for industrial shaping. The shaping methods were presumably first worked out by the late Neolithic farmers, who were also part-time miners, prospectors, and smelters in the hilly region of northeastern Iran.

Decorative Techniques

Most decorative techniques, on the other hand, were presumably worked out once the refined raw material had arrived by barter in the developed urban civilizations of southwestern Iran, Mesopotamia, and Egypt by individuals who gradually became a distinct class of worker—the goldsmiths and the silversmiths.

Repoussé

Vaphio Cups The Vaphio Cups (15th century bc) were found in a tomb at Vaphio, near Sparta. Their origins, which are not certain, are either Minoan or Mycenaean. They are made of two sheets of gold fastened together. One sheet is left smooth for the inside; the other is done in repoussé relief for the outside. The scenes on the cups depict a ritual involving bull catching.Bridgeman Art Library, London/New York

Decoration relies on the relative softness of metals. The earliest in use probably derived from the same beating processes employed for shaping, for it is possible to furrow or ridge metal by blows upon the surface (or, with sheet metal, from the underside); this gives the pleasing effect of parallel ribs seen on copper cups and bowls, found, for instance, in the royal graves at Ur. More localized and selected hammering can raise anything from simple bosses to whole pictorial effects in relief. This technique, usually known as repoussé, has been used for over 4000 years; it reached its greatest elaboration in 16th- and 17th-century Europe on precious gold and silver utensils for church and domestic use.

Engraving and Chasing

Linear patterns can also be made on surfaces either by removing a narrow fillet of metal with a cutting or graving tool, or by depressing the surface with a blunt point and hammering along the line to be delineated without removing any metal. The former is called engraving and the latter chasing; these techniques are mostly reserved for precious metals.

Matting, Etching, and Oxidization

Another method of surface decoration is to impress it with repeating patterns of hatched lines (again, usually used on precious metals), thus matting or breaking up areas to contrast with other areas left polished and reflective. Yet another method of darkening selected areas is to etch them with acid, a technique mostly used on steel armor and the steel parts of weapons. In the 19th century a process called oxidization was devised; with it, a subtle darkening effect was achieved on polished silver surfaces with a pickling process using sulfur.

Gilding and Inlay

Luxurious decorative effects may be achieved by applying one metal to another or by inlaying a precious metal into a less precious one. Such, for instance, are the techniques of gilding or parcel-gilding silver, bronze, and steel objects and of inlaying silver and gold wires into brass and bronze. The latter was perfected in the Arab world in the Middle Ages; it is called damascening, after Damascus, a Syrian city particularly famous for such work. In the 1st millennium bc, Chinese ceremonial bronze vessels were exquisitely inlaid with gold and silver.

Granulation and Filigree

Other surface decoration techniques using metal on metal are granulation and filigree. Granulation, used for jewelry, is only possible with gold. In granulation, beads of gold are soldered onto gold surfaces; the finest of this work was produced by the Etruscans in the 6th and 5th centuries bc. The beads were so minute as to give the appearance of a bloom to the gold surface, rather than of a beaded surface. Filigree can be made of both gold and silver; openwork patterns are worked from minute cables made of two or three twined or braided gold or silver wires. Filigree was extremely popular in the 16th and 17th centuries to decorate vases and drinking vessels, especially in Italy and Germany, as well as in 18th- and 19th-century South America. In Russian and Scandinavian countries filigree has survived as a provincial craft and is used for boxes, mirror cases, and peasant jewelry. It is obviously fragile work and, except for jewelry, usually has a backing material.

Similar openwork effects are called ajouré, mostly used to ornament domestic silver and some jewelry, and are achieved by cutting or piercing patterns in the metal. Ajouré was most popular from the late 17th to the early 19th century. Conversely, raised patterns can be made by soldering small castings or cutout motifs onto a flat surface, a method of decoration in use for over 4000 years.

Embellishment with Other Materials

Frankish Jewelry These two fibulae, or decorative pins, from the 6th century were used to fasten clothing. They are about 10 cm (4 in) long, made of gold and bronze, and decorated with garnets and niello work. They were originally found in the Charente area in France and are now part of the collection of the British Museum, London.Bridgeman Art Library, London/New York

Every civilization with a wealthy or high-status class has, for over four millennia, used decorative metalwork embellished with other materials. These include precious and semiprecious gemstones, enamels (including niello, a black finish), a variety of exotic substances such as rare woods, ivory, jade, and amber, and reverse-painted and gilded glass (verre églomisé). In ancient times ceremonial furnishings were almost as exotically decorated as personal jewelry and cult implements. In more recent times this type of decorative metalwork has tended to be reserved for personal objects, including jewelry.

Metalwork as Art

In considering the use of metals in art, it must be remembered that only since the Industrial Revolution has a clear distinction been made between machine-made useful objects and handcrafted fine and decorative art objects. For thousands of years, until the mid-18th century, everything was of necessity handmade; useful objects were almost always shaped and decorated to have aesthetic appeal, although pieces that might now be considered purely fine art—such as statues and jewelry—served deeply serious religious or ceremonial functions.

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