My fascination with pearly white Chinese porcelain glazed with various ethnic designs began on a school trip to the San Francisco Museum Of Modern Art. I spent a good deal of the day wandering among the different rooms of an exhibit of Chinese art forms, of which I found the blue and white porcelain to be my favorite. The elegantly shaped pieces were covered in delicate pictures of dragons, monkeys, and Chinese characters, all rendered in various shades of vibrant blue. I did not find it difficult to understand why this method of pottery was appreciated worldwide for it’s aesthetic beauty.

Chinese porcelain was made by combining two materials, china-clay and china-stone. The finished piece would display qualities of both, making porcelain unique from other oriental decorated pottery of that era. China-stone, a feldspar of either sodium or potassium, was found naturally in granite and other indigenous rocks. China-clay was the result of the decay of feldspar, where the potassium or sodium is lost and the substance gains water molecules. When these two substances were combined, the resulting porcelain had a certain plasticity, like the china-clay, and when fired it would fuse and become transparent, as china-clay did. This porcelain was also much stronger than stoneware when fired, allowing Chinese potters to create shapes with very thin walls without compromising the strength of the piece.

The process of creating a finished blue and white porcelain piece began with shaping the clay body and letting in dry. Cobalt oxide was then painted on the unglazed and unfired piece. The piece was dipped in an opaque white glaze and fired to a temperature between 1250ºC and 1300ºC. The opaque glaze became transparent, giving the piece a clear, glassy surface that allowed the brilliant blue designs beneath to shine through. This process differed from the creation of other pottery in that the porcelain was only fired once, making this method of pottery decoration very economical. This quality, combined with the fired piece’s rare beauty and delicacy, made blue and white porcelain one of the famous Chinese art forms.

The clarity of the blue design on the finished piece depended on the purity and concentration of the cobalt oxide. If the cobalt oxide was contaminated with iron or manganese, the resulting blue became grayish and lost its vivid color. Since China did not have a pure source of this substance, it was necessary to trade for this expensive item. China’s answer to this dilemma was to purchase some of the pure substance and then mix it with the impure cobalt oxide available within China. Concentration also affected the shade of blue, with the glaze becoming red-black in areas of high concentration and paler where there is less glaze. Thus, Chinese potters became masters of the many different variables affecting the end-result of the porcelain piece, including the composition of the clay body, piece shape, firing temperature and the application of glazes.

The exact beginning of blue and white porcelain is unknown, but it is accepted that Persian and Islamic potters first used the method of painting in blue under a transparent glaze early in the thirteenth century. The quality of these pieces was inferior to those later developed in China because the blue glaze had a tendency to run. The Chinese method of manufacturing blue and white porcelain differed from other early attempts because both the clay body and the glaze were felspathic. The similarity in the materials meant that they fused almost completely during firing, accentuating the blue designs because of the transparency of the piece’s surface. Thus, due to its high quality and beauty, Chinese blue and white porcelain became the most prominent product of its type.

It is currently believed that the Chinese first began to develop blue and white porcelain at the beginning of the fourteenth century, during the Yuan Dynasty (1279-1368). Some primitive blue and white pieces have been found that appear to be of the T’ang Dynasty (618-906). Although these pieces may be of the blue and white style, it is much more evident that it was during the Yuan Dynasty that Chinese potters began refining the art of blue and white porcelain production. This method of pottery decoration was finally perfected during the Ming Dynasty (1368-1644).

The Yuan Dynasty was established by Kublai Khan when he led the Mongols to conquer China. As part of a huge empire that maintained a laissez-faire attitude, China experienced a period of increased foreign trade and artistic freedom that led to many new ideas and practices. Among these was the creation of blue and white porcelain. Interestingly, this decorative technique was such a deviation from the classical artistic tastes of the previous Sung Dynasty (960-1279) that it gained appeal very gradually. It was even viewed by some traditionalists as vulgar and gaudy. Despite this controversy, blue and white porcelain became popular overseas during this period, as is shown by the large collections in Iran, Istanbul, Egypt, Syria, Indonesia and the Phillipines.

The production of blue and white porcelain reached its zenith during the Ming Dynasty. Manufacturers of porcelain became more adept at the glazing techniques, making them more complex and bold. The potters became able to produce perfectly white porcelain, and the innovation of glazing techniques allowed artists to experiment with glaze textures, shades and concentration. One such technique was using glazes full of fine bubbles to give the piece’s surface a soft texture. Another method was to make glazes thicker and apply them unevenly in order to produce an “orange peel” effect. It was also during this time period that blue and white porcelain gained the approval and admiration of the Imperial court. Porcelain production increased – “popular wares” supplies the huge domestic demand, superior quality “imperial/official wares” were destined for the courts, and “export wares” were sent to other countries, sometimes with foreign shapes and designs.

During the middle of the Ming Dynasty the demand for blue and white porcelain continued to increase. The export trade expanded, with more pieces of magnificent quality being made for foreign monarchs and rulers. The motif on porcelain pieces also changed, favoring symbols that related to the faith and desire of whatever emperor ruled China at the time. In the early 16th century, many pieces displayed Islamic influences, such as quotations from the Koran. The succeeding emperor expounded Taoism, and thus pieces from this era were decorated with the Eight Taoist Emblems, the Eight Trigrams of the I-Ch’ing and popular Taoist symbols like the crane, the deer and the character Shou (meaning longevity, usually depicted by a sinuous peach tree).

During the last 100 years of porcelain production in the Ming Dynasty were considered transitional, with the West demanding large amounts of porcelain pieces. Thus, to some extent, quality was forsaken for quantity, and the majority of porcelain pieces were exported. However, this transitional phase came to an end along with the Ming Dynasty. As the Ch’ing Dynasty began its reign, blue and white porcelain became more technically advanced than ever before. Vibrant azure lines traced graceful arcs upon pure, white translucent surfaces. The images portrayed on the vast assortment of pieces were creative and varied greatly in subject matter. Unfortunately, with the decline of the Ch’ing Dynasty, blue and white porcelain production also deteriorated.

Today only museums and private collections house examples of the astounding beauty that Chinese potters were able to achieve using porcelain and cobalt oxide as a medium. These relics attest to the skill and talent of the artists who developed their trade throughout the rise and fall of the Chinese dynasties.