The most highly prized of all Chinese ceramics. Ju wares were produced exclusively for the Northern Sung emperor Hui-tsung from about 1107-1127. The original kiln site, Ch'ing-liang-ssu, yielded 37 examples. The undecorated bluish- or greenish-gray glaze of Ju wares is cloudy and opaque, often with a pale blue or lavender tinge and fine irregular crackle. This glaze typically covers a gray stoneware body that has a simple, exquisitely elegant shape.