This shard is part of a Qingbai bowl. It is made of porcelain – a hard, white and translucent ceramic that can be fired up to 1350°C. The bluish tone of the glaze is attributed not just to the presence of iron oxide but also to the relatively high content of calcia (calcium oxide). The techniques of incising and combing were used to decorate the bowl. The bowl was fired in a reducing atmosphere at around 1300°C. The mark left on its base suggests the use of a circular support.
