Author: Tao Hsu, Kirk Makepeace, Andrew Lucas, and Nikki Makepeace
10/26/2015
This article from GIA is one of the best I've seen on Nephrite, and the photos are fantastic! Below is just one small snippet of the extensive article that shows Nephrites from around the globe. Wait til you see the back-lit wall behind the stove, and the gorgeous, huge Canadian boulder!
COMMERCIALLY IMPORTANT SOURCES
Green nephrite occurs along the contacts between serpentinite units and more silicic (rich in silica) rocks such as granitic intrusive bodies, argillite, chert, or greywacke in obduction settings, where continental and oceanic crusts collide (Harlow at al., 2005). Its formation results from metasomatic reactions promoted by the presence of calcium-rich hydrous fluid along the contacts (Harlow et al., 2005).
Although deposits around the globe share a similar geological setting, there is no single formation model. Since serpentinite belongs to ophiolite belts and ophiolite is of oceanic origin, it’s only transported to land by subduction or obduction. Subduction and obduction occur during continental-oceanic collisions, so most ophiolite belts occur along old suture zones and current subduction zones.
Major green nephrite deposits form within serpentinite belts along old or still-active subduction zones. The three most commercially important deposits—in China, British Columbia, and Siberia—all have similar geological environments. Map adapted from Harlow and Sorensen, 2005.
The most economically important green nephrite sources are located in northwestern China, British Columbia, and Siberia. They are all major suppliers for the China market. :
http://www.gia.edu/gia-news-research/ne ... ite-market
also never knew about nephrite deposits in Japan 
and this was 1st nephrite quarry in Europe (now closed) - i've posted some photos from there but I'm not sure where ? some time ago I was in the museum just to see nephrite from this location 
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