24-The Transformation of Matter.Pub

Natural and artificial processes Matter is transformed chemically or physically in a natural or artificial way. In volcanic activity the minerals are changed into magma which then so- lidifies into a vitreous structure and the clay becomes a more or less stable substance through the action of the sun or fire. Through observation of such phenom- ena man discovered the application of this transformation to pottery and in due course learnt how to control the process. Ceramic materials and their transformation The ceramic body is obtained by the transformation, through heat, of various minerals, essentially silica and alumina. Today, however, the meaning of the word ‘ceramic’ has been vastly ex- tended to include products made from other raw materials. The basic ceramic ingredients are ball- clays and china-clay which have the essential property of plasticity, allowing them to be modelled and to retain the resulting form when the water is driven off by firing at a minimum temperature of 200º. 24. THE TRANSFORMATION OF BASIC MATTER From empiricism to science From its origins up to the eighteenth century the ceramic art developed in the light of experiments and empirical knowledge to reach a high point of achievement before the rationalization of chemistry as a branch of science. In the nineteenth century various scien- tists such as Alexandre Brongniart and Herman Seger systematized the behav- iour of ceramic materials and so laid the foundations for the emergence of industrial techniques which could control the process of manufacture down to the smallest detail. Traditional manufacturing processes Ceramic production involves three basic operations – forming, drying and firing – but in the course of time the process of manufacture has varied, with the introduction of more sophisticated im- plements. Since the discovery of the potter’s wheel c.3400 BC, in Uruk (Mesopotamia) pots have been made in very similar shapes in various parts of the world and in workshops whose equipment varied little before the industrial age. 24. THE TRANSFORMATION OF BASIC MATTER The ceramic art emerged in the Neo- lithic period and developed in parallel with the history of the human race, showing different styles and techniques. The production of each culture and civilization had individual charac- teristics which allow us, with the aid of archaeology and ethnology, to chart its development. The study of pottery involves art, be- liefs, techniques, ideas, everyday hab- its and social customs – in short, the history of society in all its aspects. Some- times the ancient traditions linger on today, a notable example being the pottery techniques still used by the Ber- bers, which go right back to the Bronze Age. In the Mediterranean world the Greek black-figure and red-figure wares of the sixth and fifth centuries BC are an outstanding achievement. Perishable goods such as wine or preserves were transported in large containers known as amphorae. At about the same time the pottery made by the Iberos shows that they introduced the potter’s wheel into the Iberian Peninsula and had the knowledge to build complex kilns. It is clear that high quality Roman pot- 25. CERAMIC AND CULTURAL EVOLUTION tery was produced on a massive scale, notably the ubiquitous terra sigillata with its ‘red-gloss’ surface. History The cupola, designed to be seen from the piano nobile, closed off the well of the eighteenth-century grand staircase. The mutilation of this staircase in the alterations of 1867 completely al- tered the concept. 26. THE CUPOLA The painting of the cupola was exe- cuted by Hipólito Rovira (Valencia, 1693-1765) on lime and sand mortar and touched up a secco, while the sculptures in the spandrels were exe- cuted by Ignacio Vergara (Valencia, 1715-1776) using piece-moulds. The bodies and backgrounds are painted in imitation of maiolica, silver-leaf being used for the clothing, the hair, the vegetal elements and the animals on the cartouches. Restoration The state of restoration of the building, which has suffered major changes throughout the years, is greatly due to humidity filtrations and to the structural movements of the building that have 26. THE CUPOLA caused the cracks. The building had been entirely repainted during various periods using different materials. To de- termine if there was any paint under- neath, a series of microscopic strati- graphies were carried out at several points, and trial tests were made on the roof using different procedures. Once the non-existence of an original layer had been ascertained, the super- ficial layers were removed. It was during this process that several characters became visible veiled by additional layers and by a stratum of grim and dirty varnish. From a dirty, varnished, very dark and opaque appearance, displaying tar- nished white satins, fungus and salts, we have recovered a light colourful, transparent painting, as correspond to a fresco. The Muslim world From the fourth century onwards, after the disintegration of the Roman Em- pire, there was a gradual decline in quality in the pottery made in the Ibe- rian Peninsula. Recovery began with the arrival of the Muslims who estab- lished the norms, both technical and functional, of popular ceramics, which governed Spanish practices until the present day. In this room can be seen objects typi- cal of the Hispano-Muslim world, mostly from the Valencian region. Among them are pots and pans for kitchen use, dishes and bowls for use at table, sanitary wares and candlesticks. Nota- ble are the tenth-century tin-glazed wares decorated in green and pur- plish-black and the Persian lustrewares, the fore-runners of the pieces which were later to spread the fame of the 27. ROOM OF THE MUSLIM WORLD potteries of Málaga, Murcia and Manises. Tile–mosaic and tiles, together with ceramic supports and other elements making up arches and vaults, were a fundamental contribution of the Muslim potters to architectural decoration and gave rise to a long tradition in the fol- lowing centuries. Especially notable in this room is the thirteenth century gar- den or courtyard fountain, of Valen- cian origin, inlaid with tiles of various shapes (aliceres) to form mosaic pat- terns. 28. MUSLIM WORLD: ARCHITECTURAL CERAMIC The Christian pottery of this period is the heir to the Muslim tradition. It owes much to the productions of the Muslim workshops which continued to operate after the Reconquest, especially in the Valencian region, but also to the work of immigrant potters from the Kingdom of Granada and other cities occupied by the Christian armies. In this way a greater variety of forms was introduced under the Christians, and pottery was used for many new purposes. The richest types of pottery from this period are the tin-glazed ‘purple and green’ wares, decorated in manga- nese and copper oxide, and the wares decorated in blue and lustre. Legal documents refer to the latter as obra de Málica (‘Málaga work’), suggesting that the technique came from there, though this has not been proved. In this room, together with a variety of glazed and unglazed wares, are displayed other types of ‘purple and green’ pottery, such as the contemporary wares of Paterna and Teruel. 29. CHRISTIAN CERAMIC. 13 AND 14TH CENTURY The fifteenth century was the golden age of Valencian pottery because of the important role played by the huge production of lustreware, called obra daurada, and the fame which it en- joyed everywhere. In particular the pottery of Manises was used by kings and the aristocracy in many European countries. The large flat dish bearing the shield of Valencia is an important example. Contemporary with the lustreware are other, cheaper types of pottery such as the Valencian wares painted in blue, some of which date from the four- teenth century, or those of Teruel, here represented by the modelled recum- bent figure of Pope Benedict XIII. At that time also polychrome pottery began to be made in Italy. An excep- tional example is the Florentine tondo from the façade of the Monastery of the Trinity. CERAMICS OF THE 15TH CENTURY MUDÉJAR 30. In the Kingdom of Valencia tiles and socarrats (large, unglazed ceiling-tiles) of high quality were produced in large numbers, in Paterna, Manises, Quart and Mislata. For their palaces Kings and nobles commissioned tiles decorated with their arms or devices – e.g. those of Alfonso the Magnanimous on display here - and the Guilds also commissioned tiles with their emblems to decorate their halls. Important examples here shown include the ceiling-tiles, and some frag- mentary pavements made up of tiles and bricks, such as those from the Pa- lacio de Dos Aguas and that from the palace of the Boil family, lords of Man- ises. 31. MEDIEVAL ARCHITECTURAL CERAMICS 3 2 1 2 1 Chest. Wood, leather. Spain, 16th century? CE3/00430 and 3/00431 Armchairs. Wood, leather and metallic nailing. Spain, 16th century. 2 CE3/01249 Virgin with Child, Saint Vicente Ferrer y Saint Jerome . Oil on canvas. 3 Spain, 16th Century. CE4/00258 31. MEDIEVAL ARCHITECTURAL CERAMICS In the ceiling can be seen a display of relief-decorated socarrats which came from the palace and display the arms of Ramón de Perellós. Also of note are some of the earliest polychrome tiles made in Spain under Italian influence; in particular those with the inscription “Mar - Pisano” which came from the vanished Palace of the Conde Real in Valencia. Also shown are arista tiles from Seville and Toledo and polychrome tiles from Talavera, which blend together influences from the Muslim, Gothic and Renaissance traditions. 32. ARCHITECTURAL CERAMICS. 16-17TH CENTURIES The Valencian lustre technique spread to Catalonia and Aragon.

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