mid-Edo period Imari ware
Historical term referring to Imari porcelain produced during the mid-Edo period, distinct from earlier or later styles.
This Ko-Imari plate is from the mid-Edo period.
Imari ware in general, including later periods. 古伊万里 specifically denotes the mid-Edo period style.
From 古 (old) + 伊万里 (Imari), referring to the older style of porcelain from the Imari region.