Northern Song/Jin Dynasty, late 11th-early 12th century Of deep conical shape, the interior with a lustrous black glaze thinning to brown at the rim, liberally splashed in russet with 'partridge feather' mottling that splashes outward from the center, the exterior with a russet brown glaze almost entirely covering the black glaze beneath save for the edge of the rim and near the foot, the foot ring and shallowly-cut base un-glazed and revealing the buff stoneware. 5 1/8in (13cm) diameter