Those two lovely plates are made from Jun Porcelain. Different from colorful Jun Porcelain, Ge celadon has a grayish-blue glaze and jade-like perfection. Carving is employed to adorn ware. Celadon production had a long history at Longquan, a city in the Southern China and related sites, but the era of greatest ceramic production was not until the Southern Song (1127-1279), Yuan (1271-1368) and Ming (1368-1644) periods.