Rather than only the soft blue-green hues of Ru wares, Guan ware was glazed in a variety of colors ranging from pale ivory to browns and greys.

But with different materials and kilns, the imitations developed a new aesthetic. It is theorized that many potters fled south along with the imperial court, and were thereafter commissioned to produce Guan, or “official” celadon ware, for use in the palace. With the establishment of the Southern Song Dynasty after the fall of the Northern Song, efforts were made to replicate the fabled Ru celadons of years past. In contrast to the all-over glaze of Ru ware, Jun ware usually has a tall ring of bare clay at the base of the piece to allow space for this glaze movement. The result is a glaze that is very thin or even absent from the rim of the piece, but thick near the bottom, where the glaze has flowed during the firing process. Jun glazes were also applied differently from Ru glazes, as they seem to have been more likely to move and drip during firing. This distinctive texture is often used to separate authentic antiques from later imitations, as the effect is not easily replicated. The “official” wares produced for imperial use are also characterized by a streaking pattern on the surface, referred to as “worm tracks” in Chinese. These later examples used copper oxide on top of the light blue glaze to create splotchy patterns of purple or red. Unlike Ru wares, Jun style pottery continued to develop throughout the Yuan and into the Ming dynasty, with “official” Jun wares commissioned by the Yuan imperial court. Together, these effects created an opalescent texture in the Jun ware celadons. But Jun ware glazes were made with lime, which separated from the silica in the glaze to create multiple layers of glass, as well as microscopic bubbles, within the glaze surface. These pieces were glazed in a light blue, similar to the color of Ru ware. Jun WareĪt the same kiln site in Henan, the earliest examples of Jun ware can also be found. Today, there are less than 100 intact examples of authentic Ru Kiln work, as the kiln site and glaze recipe were lost in the fall of the Northern Song Dynasty. However, there is some evidence that this effect was not originally intentional, and Ru pieces without this crackling effect were actually considered more valuable. Ru wares are also notable for a network of fine crackling in the surface of the glaze, which has been considered aesthetically desirable in Chinese celadons ever since. The all-over color and thick, unctuous glaze texture created a resemblance to jade, the most revered material in Chinese art, and a common symbol of the emperor. To prevent the glaze from fusing the piece to the shelves or protective saggars in the kiln, each glazed piece was set on small spurs, which left small “sesame seed” dots in the smooth surface of each glazed base.

Authentic Ru ware pieces were also fully covered with glaze, including both the rim and base of the piece.

Ru wares are characterized by their celadon glaze, which is always a soft bluish hue with hints of green. The high quality Ru ware pieces were reserved exclusively for imperial use, with some sources claiming that any pieces deemed subpar were immediately destroyed. A kiln site discovered in the 1950s in Henan was the production site for all Ru wares, though the large compound also made ceramic works in other contemporary styles. The first, and perhaps most legendary, of the Five Great Kilns was the Ru Kiln. Ever since, these distinct celadon glazes have been coveted and imitated, forming the inspiration for potters throughout history, in China and across the world. Later writers in the Ming and Qing dynasty identified Five Great Kilns of the Song Dynasty, memorializing these styles and securing their legacy. In the Song Dynasty, around the same time that Chinese literati were developing tea culture into an art form, potters across China were creating the first true celadon glazes, colored with iron oxides and fired at high temperatures. The aesthetics of these early potters would become legendary, retaining popularity even into the modern day. China has a long history of ceramic artistry.

Pottery bubble crackle glaze effect