Techniques Paper
Chinese Ceramics
A Brief History from the Paleolithic Period – Ming Dynasty
Ceramics, a term generally used today interchangeably with “pottery”, essentially refers to any object made of fired clay, both low- and high-fired. (Technically, however, pottery is synonymous with low-fired earthenware, not high-fired stoneware and porcelain.) Ceramics is the most ancient of Chinese arts, earthenware shards having been found at Yuchanyan in Daoxian County, Hunan province from the Paleolithic era that archeologists have determined to be at least 14,000 years old. Neolithic sites throughout China, where large amounts of pottery have been discovered, number in the thousands. It is during this era (10,000-2100 B.C.E), particularly from about 6000-5000 B.C.E., that people increasingly developed a more sedentary, agrarian lifestyle, coinciding with improvements in agriculture. Perhaps not surprisingly, pottery-making is believed to be closely associated with the development of more settled communities in that it specifically advanced cooking techniques. Moreover, China is blessed with ample clay-rich soils which are well-suited to both growing crops and making pottery, a fortuitous combination of attributes that provided opportunities for continued technological improvements in both over the next several millennia. Nevertheless, during the Early Neolithic, earthenware was fairly crude and utilitarian. These objects were made by hand generally for domestic use. Pottery was fired over open fires at low and uneven temperatures so items were fragile. Earthenware from this era was also basically reddish is color due to the oxidization of iron oxide in the clays used.
For purposes of this paper, two major technological advances occurred between 6000-4000 B.C.E. The first was the invention of the kiln in about 5500 B.C.E. The second was the invention of the pottery wheel which came into use sometime between 3300-2800 B.C.E. In addition, as cultures advanced, so did their artistic sensibilities. Pottery moved out of just the domestic sphere and into the funerary and decorative. However, it would not be for several thousand more years before the first high-fired stoneware appeared in the late Shang – early Zhou Dynasties (1600-1046 B.C.E.) , also marking the first time white kaolinic clay, one of the two primary constituents of porcelain, was widely used for white bodied vessels. (It should be noted though that the kaolinic clays used during this time were not what would come to be known in Western terms as “proto-porcelain”. They were used instead for fairly thick-bodied handmade vessels, the clays lacking in the plasticity associated with earthenware and stoneware. The other essential ingredient for making porcelain, a feldspar-rich mineral known as “China stone” or “petuntse” would not be first combined with kaolinic clays until the Later Han Dynasty (25-220 C.E.). Furthermore, “proto-porcelain” is not a term used consistently between the East and the West, the West focusing more on early white high-fired wares and the Chinese focusing more generally on early glazed high-fired wares placing some emphasis on the celadon glazes used. Thus, to make things more confusing the term “proto-porcelain” is sometimes used interchangeably with “proto-celadon”, depending on the source.)
It is far beyond the scope of this paper to address all the developments that occurred in Chinese ceramics between the beginning of the Shang Dynasty and the end of the Ming Dynasty, a span of over 3200 years, but it has been done! And for those inclined to dig deeper, I direct you to the hugely comprehensive (and just huge) Chinese Ceramics from the Paleolithic Period through the Qing Dynasty, edited by Li Zhiyan, Virginia L. Bower and He Li, 2010. See also, The Chinese Potter, a Practical History of Chinese Ceramics by Margaret Medley, 1986.
What is Porcelain?
While scholars date the birth of porcelain, the result of a relentless search for a pure white-bodied stoneware, to the Tang dynasty in the late eighth-early ninth century, manufacture on a broad scale did not occur until the Yuan dynasty (1279-1368). However, it is now believed that porcelain, sometimes referred to as “mature porcelain”, was actually first created, as noted above, in the Later Han Dynasty (also called the Eastern Han) between 25-200 C.E. Its name derives from the Italian word for cowrie shell, “porcellana” because it resembles the shell’s translucent surface. (When Westerners refer to porcelain simply as “china”, it is because porcelain came to be so closely associated with the country of its origin.)
Fittingly, porcelain’s manufacture has been described as “having something in it of alchemy” as the conditions and constituents required for its successful transformation from clay to the white, beautiful, but strong and impermeable finished product, are considerable and exacting. (Ming Porcelain, p. 20) First, there are two critical ingredients to its composition. One is a clay called “kaolin” of which there are massive deposits in China, particularly in the hills from which it derived its name in the district of Laoling about 20 miles from Jingdechen, a city that ultimately became known for the quality of the porcelain manufactured there starting in the Yuan dynasty.
Kaolin is a white-firing, fairly non-plastic clay that is only fusible at temperatures too high to be practicable so it has to be mixed with a second ingredient that melts somewhat more easily called white China stone or “petuntse”. Petuntse means “little white brick” because it is a felspathic material derived from decayed granite that is ground into a powder that when washed and dried is formed into little white bricks for easy storage and transport. The Chinese call these two ingredients the “bones (kaolin) and flesh (petuntse)” of porcelain (Ming p. 20), the highest quality porcelain containing about equal quantities of each. Once mixed, the clay is traditionally allowed to weather for a long period of time, sometimes years. Next, it has to be kneaded to be uniformly blended and only then is it ready to mold or throw on a pottery wheel, different parts of complex objects fashioned separately and joined together with a “slip”, a white firing clay diluted to a thick creamy consistency. Finally, it is ready to be fired in a kiln at temperatures upward of 1280 C, generally between 1300-1350 C.
When porcelain is fired it becomes vitrified and translucent. Thus, it is impermeable, but not terribly attractive. So, it is generally glazed for aesthetic reasons to which more attention will be given in the next section of this paper, as well as to other types and techniques of decorating. For now, suffice it to say that there are two basic types of glazes and glazing techniques: There are high-fired, often felspathic glazes that will fuse to the “body” (defined as the ceramic piece distinct from its glaze) applied before the object is initially fired. There are also low-temperature glazes generally made out of lead that are applied to the object after the initial firing which is then fired again at low temperatures. (The body after the initial firing is generally described as the “biscuit”.) Glazes may contain additives of various metal oxides other than the main glass former that can lower their melting temperature. They can also contain a wide variety of colorants such as cobalt, copper oxides, iron oxides and manganese. When decoration is applied under the glaze before firing it is generally referred to as “underglaze”. When several coats of glaze are applied to a piece, or, once glazed, a non-glaze substance such as enamel or gold leaf is applied, the decorative technique is referred to as “overglaze.”
Tall Vase with Garden Rock, Birds and Flowers
Chinese, Ming – Qing dynasty,
17th century, Jiangxi Jinghechen
Porcelain painted with blue underglaze
With this background, we can now focus discussion on the techniques used to make the Tall Vase with Garden Rock, Birds and Flowers and the time period during which it was made. It was crafted in the seventeenth century, but we do not know whether it was made during the latter years of the Ming dynasty (1368-1644) or during the early years of the Qing Dynasty (1644-1911). In fact, the time between about 1620-1680 is often referred to as the “Transitional Period,” and, accordingly, certain wares made during this period were called “transitional wares”, generally pertaining to those made in private (versus government) kilns at Jingdechen. These porcelains, characterized by less rigidly arranged designs, were quite popular, particularly in the European export market, which grew substantially after about 1600.
Another reason that we do not know exactly when it was made is that it lacks a reign or dynasty mark which was inscribed on goods produced for the imperial palaces, but not generally on wares destined for other domestic or export markets, a practice started during the Ming . Perhaps, at least according to some scholars of Chinese ceramics, the significance of knowing the year the vase was made would be diminished in that there is a fairly widely held belief that porcelain craftsmanship reached perfection during the Ming and few major changes were thereafter made. Rather, it was often the case that the most admired Ming pieces were commonly imitated during the Qing.
The Ming dynasty followed a long period of foreign domination by the Mongols who were not pushed back to the northern frontiers of China until 1368. Thereafter, at least during the first part of the Ming, it was a time of great expansion as the new emperor reunified the empire, restored the economy and encouraged crafts and industry. (Ming actually means “brilliant” or “bright”.) It was also during the Ming that the first direct contacts between the Chinese and the Europeans took place and that porcelain came to be admired by people the world-over.
The center of porcelain production as noted above, was at Jingdechen which is situated in the north of the province Jiangxi. The city was particularly well situated not only to the raw materials (kaolin and petuntse), but also to ample sources of wood for fueling the kilns and to water, and with ready access to coastal ports. Kilns had been operative at Jingdechen since the seventh century, and white porcelains of the Sung dynasty (960-1279) were made there, although before the Yuan dynasty (1279-1368) it was only a small village. By the end of the Yuan, it had grown considerably and would soon become the porcelain capital of the world. By the fourteenth century, the manufacture of porcelain was almost exclusively done there.
Although it has been suggested that the first Ming emperor, Hung-wu, established an imperial kiln (meaning one directed by a responsible official representative of the emperor) at Jingdechen, it is generally believed that no true imperial kiln was established until the Qing dynasty in the seventeenth century. Nevertheless, extensive demands were certainly placed by the imperial court on the kilns of Jingdechen and much of Jingdechen’s output was for the court. But the home and export markets grew in importance as well, especially as a wealthy urban middle class emerged in China in the sixteenth century whose tastes included porcelain wares to display for domestic and religious purposes.
The work at Jingdechen was greatly subdivided with as many as thirty-three separate departments. Every piece was subject to many processes and changed hands for nearly every one of them, including: preparation of the clays and colors, molding or throwing, finishing, decorating, enameling, and inscribing the reign marks. Unskilled laborers were needed, too for auxiliary services such as extracting and transporting clay, making saggars (the box or case in which ceramic wares are placed for firing in the kiln for protection from uneven firing or ash-fall) felling trees for wood fuel, packing, reloading etc.
It is to one of the last of these processes, the decorating of the porcelain, to which we now turn. Underglaze painting in cobalt blue was the most common type of decoration practiced under the Ming, hence the name “blue and white” given to these wares. During the seventeenth century the cobalt used was of local origin, called absolite, which contains a high percentage of manganese. While it was once thought that the most brilliant blues were achieved from imported cobalt, that theory has been discredited, the quality of the blue instead depending on a number of other factors, including, among others, the presence of iron impurities, the conditions of firing and the thickness of the cobalt and/or the glaze. The cobalt was ground into a powder and mixed with water and then applied with a brush, a highly unforgiving and delicate process analogized to “trying to paint on blotting paper” (Ming, p.21), thus undertaken only by highly skilled craftsman.
So now that we know how the painter craftsman applied the paint, let’s turn to the scene he painted. First, the design would not have been haphazard, but laid out with great care and deliberation related to, or even dictated by, the shape of the vase, to set off to greatest advantage the surface provided and to probably emphasize the wide curve below the neck. Second, we can be virtually certain that the motif is replete with auspicious symbols as this style of decorating dominated porcelain painting in the Ming. And, by the Qing, this trend had evolved to the point that the painting must be auspicious. Basic themes such as those involving dragons, tigers, phoenixes and other mythical and wild beasts, horses, landscapes and emblems or objects were certainly common, but by the end of the Ming, themes and motifs of flowers and plants were the most widely applied, representing symbols of longevity and prosperity.
A favored motif during this time appears to be that which is represented here: sprays of chrysanthemums and peonies, the latter specifically symbolizing riches and prosperity. Flowers are sometimes used, too to depict the “Four Seasons”. Birds (here resembling sparrows) are realistically drawn, with attention given to the habits and peculiarities of the species. They may also have a specific meaning (e.g., a pair of mandarin ducks to demonstrate wedded bliss) or may simply add charm and a sense of liveliness to the scene depicted. Chinese landscape is often limited such as here to representing a garden or terrace, but in the sixteenth and seventeenth increasingly became the background for human figures as well, although none are present here.
Finally, with regard to the painting, note that there are actually two separate categories of motifs on the vase, typical on Chinese porcelain, but like so many other things, becoming a firmly established practice during the Ming. The primary category is the basic theme by which the piece is defined as described above, but there is also a secondary motif seen here on the neck of the vase. It is intended to form a border that can also serve to emphasize the division of the body from the neck of the vase, here comprised of a simple leaf-like pattern.
After it was painted, the porcelain was ready to be glazed. The classic glaze for porcelain is, not surprisingly, white. (However, Ming glazes are almost always slightly blue-tinted from iron impurities remaining in them. Ming copies from the eighteenth century have pure white glaze as the impurities were carefully removed and ironically are not considered as beautiful.) It is made from a mixture of finely ground petuntse, fern ash and a small amount of chalk which is diluted with water to form a creamy paste. It is applied by brush, dipping or blown through a bamboo tube with a piece of gauze over the end. Now, the final, and most critical step: firing.
The kilns at Jengdechen during the Ming were primarily high capacity single chamber, somewhat bottle-shaped and built into sloping ground. The chamber contained several openings into the chimney. The objects were arranged in saggars that could be stacked, with the pieces fired upright and the rim of the foot left unglazed and placed on a bed of sand and kaolin to prevent sticking. The saggars were then stacked in columns with the most valuable pieces placed near the center where the heat was most even. Firing time depended on the size of the piece and technique. For a blue-and-white piece such as our vase the firing could last as long as fourteen days starting with a lower heat and moving to a higher heat, followed by several days of gradual cooling.
There are two methods of firing, “reduction” and “oxidizing” and while we do not know for certain which was used with our vase, it was probably reduction, based on the color of the blue (fairly light). In addition, in reduction firing the glaze assumes the more bluish tint, characterized by Ming porcelain. In the reduction process, the amount of air entering the kiln is minimized, a lot of smoke is produced, primarily carbon monoxide, that extracts the oxygen from both the body and colorant of the piece. The cobalt oxide is transformed into a silicate, the blue produced being very pure. In the oxidizing process, air is allowed to circulate more freely, especially during cooling and the cobalt thus oxidized, produces a more blackish blue. Once fired and removed from the kiln, an underglazed blue-and-white piece was considered complete and ready for shipment to its final destination.
Prepared for the Santa Barbara Museum of Art Docent Council by Mary Ellen Hoffman, 2014.
Bibliography
Chinese Ceramics from the Paleolithic Period through the Qing Dynasty, edited by Li Zhiyan, Virginia L. Bower and He Li, 2010.
The Chinese Potter, a Practical History of Chinese Ceramics, Margaret Medley, 1986.
A Handbook of Chinese Art, Margaret Medley, 1964.
Ming Porcelain, Daisy Lyon-Goldschmidt, 1978.