Generally speaking, from the embryo color of qualitative, glair can see its time and kiln opening, for example, be apart from today the green glair china of the times of 2500 many the Warring States year ago, weigh primitive celadon again, it is the low level of celadon, its embryo is hoar and dust-colour, the embryo is qualitative hard, porcelain changes rate color of taller; its glair is blue, glair layer is thinner, bad distribution, because use drop glair method to undertake using the reason of glair at that time,this isThe glair color when the Five Dynasties is reddish black color, say as it is said, chai Shizong of the Later Zhou Dynasty of the Five Dynasties points to the sky that the sun shines again after rain, say to the official to color of enamel of for use of an emperor of his ask for instructions, rain spends broken part of reddish black cloud, so color is made in the future, so, the enamel of the Five Dynasties is decided to be reddish black color by admire, color of glair of this kind of glair jade-like stone embellish, apply glair thinner, there is light blue in bluenessThe plum green glair of kiln of Song Dailong spring, this is the optimal color of Song Dailong spring, it is the masterpiece in green glair, its color can be rivalled with advanced halcyon, glair layer is thicker, glaze brightness, bo changes rate tall, glaze does not open grain piece, qualitative jade-like stone be like jade, its are growing in tree of lubricious approximate plum " plum "The fetal glair of the Jiangxi china of happy, Xuan De, clear Dai Kangxi provides Ming Daiyong each characteristic, always happy period white glair the most negative great reputation, enamel fleshy, if embellish piles fat, pure Bai Shiyu, glaze light is clean look of embryo of glittering and translucent; is simple white, the embryo is qualitative exquisite, and have bad distribution appearance, if fluoroscopy falls to be able to see fetal glair shows a kind of pink in strong light, the flesh the tendency with red or gules shrimp, this one feature, be done not have in other chinaBetween bright generation Xuan Denian, with Ming Yongle year although a time is close, but color of porcelain embryo glair however widely different, same containers esp. for use in the house, always happy embryo is thick, announce heart embryo is thin, xuan Deshi is big carve implement bottom does not have glair more, the place that show a fetus often has gules place, common says " flint erythema " , still have ferruginous spot, the china of copy announce heart when Qing Kangxi Yong Zheng does not have this featureThe fetal glair of the china when clear Dai Kangxi, fetal description is detailed white, the embryo is qualitative pure, exquisite and hard, compare with the photograph of same containers esp. for use in the house of each dynasty, its carcass is the heaviest, in addition, of this one period same implement, often apply two kinds of white glair, implement inside, lip, implement outsole applies powdery white glair, its glair is rarer, often see have small shrink glair phenomenon, bottom comes back in embryo of existing still base grain trace, implement apply bright green glair personally, its glair jade-like stone embellish is shining, fetal glair is united in wedlock extremely firm close, a household utensils applies two kinds of glair, it is clear Dai Kangxi year the biggest characteristic of a manufacturing chinaIn addition, in recent years, use scientific instrument to detect the time that the technology will come to differentiate ancient pottery and porcelain also made a kind of commonly used important instrument