Pure white light is a continuous spectrum from red to purple, but when white light passes through colored gemstones, a certain color or wavelength can be absorbed by the gemstones, resulting in one or several discontinuous points in the spectrum of white light, which appear in the form of dark lines or dark bands. Many gems show characteristic patterns of absorption bands or lines in the visible spectrum, and their complete patterns are called "absorption spectra".
The absorption line of 437NM is one of the identification criteria of "A" grade jadeite.
Extended data:
First of all, the origin of this name-
There are several explanations for the origin of the jade name. A name from a bird. This bird has very bright feathers. The male feathers are red, the female feathers are green, and the famous kingfisher (also known as the green feathered bird) is collectively called jade. So there is a saying in the industry that Fei is a man and Cui is a woman. In the Ming Dynasty, Burmese jade was named "Jade" after it was introduced to China. On the other hand, ancient "Cui" refers to emeralds produced in Hotan, Xinjiang. After the emerald was introduced into China, it was called "Fei Cui" to distinguish it from Hetian jade, and then it gradually evolved into "Emerald".
Second, the distribution of origin
Most of the high-quality jadeites in the jewelry market come from the Quaternary and Tertiary conglomerate layered jadeite deposits in the Ulu River (River) basin in northern Myanmar. They are mainly distributed in Kachin State in northern Myanmar, with a length of about 240 km from north to south and a width of 170 km from east to west. 187 1 year, several major mineral deposits were discovered in Lu Wu, Myanmar (also known as Wu Jia, Wulong and Lu Wu), among which four are the most famous, namely Dumao, Myanmar, Panmao and Nannaimao.
Primary jadeite is mainly composed of white jadeite with various green tones, brownish yellow and light purple. In addition to jadeite, there are diopside, amphibole, aegirine and albite, and green jadeite rarely reaches the gem level.
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