There are two kinds of jade: soft and hard. Usually, jade refers to nephrite. It belongs to one of the most common jewels.
According to "Tengyue Local Records" written by Qing Jinshi Cun Kaitai, "Tengyue is a collection of jade articles, made into utensils and sold to various provinces in Yunnan. Top grade jadeite is mostly sent to eastern Guangdong, Shanghai, Fujian, Zhejiang and Kyoto.
Nephrite standard:
1. color: white is the best, and suet jade is the best. Other colors are also good. Topaz and purple jade are rich in color, while jet is rich in ink. The color of jadeite is transparent.
2. Type: Hetian jade is the best, and other jade species are also good.
3. History: Ancient jade is the best. Regarding the classification standard of ancient jade, some people think that jade in the Republic of China is ancient jade, while others think that jade before Han Dynasty is ancient jade. My humble opinion: It is better to classify jade before Ming Dynasty as ancient jade.
4. Carver: Nephrite is different from jadeite, and nephrite pays more attention to carver.