1. Desilication products of residual granite slurry invading ultrabasic rocks under high pressure.
2. Primary albite is decomposed into jadeite during regional metamorphism. Or that albite first formed glaucophane schist with low metamorphic degree and then further metamorphic jadeite under the action of compressive and torsional stress and low temperature caused by plate collision.
3. Granite dikes and light gabbro dikes are metasomatized under the pressure of 12 ~ 14 kPa under the action of hot water solution with high sodium potential.
4. According to the discovery of water ~ methane ~ jadeite three-phase inclusions in jadeite rocks, it is considered that jadeite is crystallized from the silicate melt of jadeite, which comes from the alkali-containing pyroxene layer widely existing in the mantle of 300 ~ 400 km.
More than 95% of the commercial jadeite on the market comes from Myanmar, so jadeite is also called Burmese jade. Myanmar is the country with the richest jade production in the world and is famous for its high-quality jade. Jade is produced in few places, only in the United States, Japan, Russian, Guatemala, Myanmar, China and other countries. The characteristic of jadeite in these countries is that few jadeite products reach the gem level, and most of them are carved raw materials.
Cele County, Hotan District, Xinjiang, China also produces a small amount of jadeite ore. Myanmar is the country with the highest output and the best quality, so jade is also called "Burmese jade".
Extended data
Emerald rough stone exists not only in Myanmar, but also in other places. Jade is a mineral found in the world. The best quality jade, that is, gem-grade jade, can only be excavated in Myanmar. There are also some jadeite deposits in the coastal mountainous areas of California, central Kazakhstan, Mexico, Guatemala and Honshu, Japan.
However, the quality of jadeite produced by these jade minerals is much lower than that of Myanmar. In this way, Myanmar has become a major exporter of high-grade jade bracelets. First look at the definition of jadeite: jadeite is a rocky and polycrystalline aggregate formed by geological conditions.
The definition of "stone jade grade polycrystalline aggregate" includes the essence of three kinds of jade: stone refers to ore, jade grade indicates that the texture needs to meet certain requirements, and polycrystalline aggregate refers to the collection of various minerals. Jade produced in Japan, Russia, Guatemala and other places is jade in mineral composition, but its texture is not up to the level of jade. So it can only be said that it is a jade in geology, not a jade in gemology.
References:
Baidu Encyclopedia-Emerald (Stone Jade Polycrystalline Aggregate)