What is a door opener? Also known as skylight. Because the raw material of jade is wrapped in a leather bag, I don't know whether it is good or bad inside, so I need to cut a piece on the raw material to observe it. This is called opening the door. Wipe the mouth means to wipe the skin off the jade with a file or abrasive belt, exposing the jade to observe its quality. However, the incision or rubbing is a local area of jade, which can't explain the whole jade, and it is very risky. It is a high technology to estimate and speculate whether there is green from local openings. What is the entrance of jadeite? The entrance of the field is the origin of jadeite. The origin of jadeite in Myanmar is also called mining area or mine. * * * is divided into six mines, and each mine is divided into many mines. Emerald produced in each field has its own characteristics in appearance, quality and color. According to the particularity of jade at the entrance, we can observe and judge whether this jade can be gambled. Sites are divided into old sites, new sites and old and new sites. These six sites are: the old site, (also known as the old pit and the old factory) ① Afraid of hillock site. There are more than 28 famous scenic spots, such as Huika, Mu Na, Oyachi, Sitongka and Pagan. (2) Mukan Courtyard, with famous entrances such as Damukan, Queping and Ba Huang. 14 & gt； More than one field. (3) Nanqichang District, there are 9 famous venues such as Nanqi and Mohan. ④ In Houjiangchang District, there are famous entrances such as Houjiang, Leichangzi, Gamo and unwarranted. 5> There is more than one field. Xinchang District (also known as Xinkeng New Factory) ⑤ Xinchang District, with more than 1 1 famous venues such as Masa Factory, Su Kai, Dewey and Muluangang. Old and new fields, also known as old and new factories, are famous for their entrances, such as Longtangchangkou.