The glaze color is yellowish for saying ‘white porcelain,’ at the same time whitish for saying ‘celadon.’ Possibly this was not intended to make ‘white porcelain,’ it can be on the way of the process transitioning from celadon to white porcelain.
The shape is not original to ceramics but an imitation of metal ware. This shape in ceramics firstly appeared in lead glazed wares from Northern Qi tombs in the late 6th century, then celadon or whitish celadon which may be on transitional stage to white porcelain from Sui tombs in Anyan, Henan province in the end of 6th century. In the 7th century, this type of white porcelain began to be unearthed in Xi’an, Shaanxi Province. In this context, it can be thought that this work dates from the Sui Dynasty, from the end of the 6th century to the beginning of the 7th century.

Publications
*the Bulletin of Chinese Ceramic Study Asssociation of Tokiwayama Bunko Foundation vol.7 Early White Porcelain, Tokiwayama Bunko Foundation, 2018 (see commentary by Sarah Sato)