Cizhou ware bowl
https://asia.si.edu/object/F1897.7a-c
<p>Bowl: rather heavily potted; low, slightly beveled foot, roughly trimmed base. Clay: Dense, light buff stoneware; resonant; darker on exposed surface of foot and base. Glaze: Thick, black (ferric oxide) high temperature, typically viscous glaze with “raven’s wing” original iridescence, streaked with iron brown which runs halfway down on inside in regular stripes, each broken …</p>