Nephrite is the main source of this gem; it comes in white, red & dark green, which is the most valuable type
The term jade is applied to two different metamorphic 
rocks that are composed of different silicate minerals: Nephrite consists of a 
microcrystalline interlocking fibrous matrix of the ... Main article: Chinese jade ... 
During Neolithic times, the key known sources of nephrite jade in China for 
utilitarian... [DOC] [TLE] Type A Jade from Burma at AJS Gems [PAR] Learn about the types of jade, the most valuable colors and the standards used to 
grade it.