Dish with copper-red glaze
Chinese monochrome porcelains are among the greatest achievements in world ceramics, and no color is more coveted than the luscious copper-red glaze perfected during the Xuande (1426–35) reign. It is no exaggeration to say that the Ming dynasty potters’ greatest accomplishment was the glaze’s creation.
Acquired in 2015, this superb dish is the first object within the Freer’s world-renowned collection of more than forty Ming dynasty imperial porcelains to feature this rare red glaze. The addition of this dish considerably strengthens the Freer’s position as a major center for the study and appreciation of Ming ceramics. Strikingly beautiful when seen alone, in the context of the collection’s other monochrome-colored and blue-and-white vessels, the copper-red dish allows us to more fully represent the Ming potters’ skill and technical command, as well as their imperial patrons’ refined tastes.
The triumph of the Xuande-period red glaze lies in its combination of color and texture. Here, millions of trapped, unbroken bubbles suffuse the glaze with a network of tiny dark speckles and subtle color irregularities that make it appear plush and velvety, enticing the viewer to touch. In fact, the dish’s surface is smooth, with only minute pitting from burst bubbles. The intensity of the raspberry/cherry color is offset by a white band around the rim, where the glaze ran thin, exposing the white porcelain body. The glaze also stops short of the foot. On the base, a six-character reign mark is written in the style of the court calligrapher Shen Du (1357–1434).
Production of copper-red glaze is extremely challenging. Only a few dozen examples from the early fifteenth century exist worldwide, in the form of shallow dishes (in two sizes, of which this is the larger) and a few other shapes. The colorant is finely ground copper oxide—half of one percent—mixed into the glaze. During high-temperature firing, reduction of the copper ions to colloidal copper metal creates the color. This remarkable hue is best known by the name jihong you (祭紅釉), or “sacrificial red glaze,” because it was used for ceremonial vessels on the Altar of the Sun (Chaoritan), one of the four main imperial altars. Early in the Ming dynasty, an imperial edict dictated a shift from using elaborate, archaically shaped bronze and metal vessels on state altars to using porcelain bowls, dishes, and ewers.
Although copper-red glaze was recreated after the Xuande reign, the same rich effect was never again replicated. Since 1985, extensive scientific analysis of the Xuande-period glaze has revealed much about its chemistry and production. Still, the process retains a touch of mystery, not least of all in trying to imagine how the potters were able to control its many complexities. The remarkable beauty of this dish inspires reflection upon China’s place as the world leader in the art of porcelain.