NEPHRITE
What is Jade?
The term ‘Jade’ is commercially applied to 2 different metamorphic rocks which are made up of different silicate materials; nephrite and jadeite. Where jadeite is a sodium and aluminium-rich pyroxene and nephrite consists of mostly microcrystalline felted amphiboles of the tremolite-actinolite series.
Jadeite and nephrite are both regarded in China as ‘zhen yu’ or ‘genuine jade’. It was not until the beginning of the 19th century that mineralogists and gemologists started to differentiate between the two. Both stones are considerably similar in appearance and physical properties when being processed. The main difference between the two are it’s chemical compositions, specific gravity and hardness, which requires advanced technology to differentiate. Nephrite jade is the official native stone of China, with over 7000 years in the country’s culture and history. Whereas, jadeite was not introduced into China until the 1800’s from Burmese miners.
BC Jade
British Columbia (BC), Canada is the largest producer and exporter of nephrite jade in the world. All of the known jade deposits in BC are of the nephrite variety, occurring at over fifty known occurrences. Nephrite jade is typically found in bedrock deposits, boulder fields or talus occurrences. The bedrock occurrences are typically lens shaped and occur at or near contacts of mafic-ultramafic rocks (mainly serpentinite).
The global nephrite market is estimated at 1200 tonnes per year, with three quarters of this originating in B.C. and the majority of the consumption is in Asia. Price of raw jade also varies significantly depending of the quality of the jade, the prices range from less than USD$10 / KG to over $1,500 / KG for the best quality jade. The best nephrite is usually bought by master carvers or high-end manufacturers and transformed into expensive jewellery or artwork pieces, which are always in demand internationally. Of BC’s different sources of nephrite, Polar Jade™ is the most famous and recognized in the world as the “brightest, most translucent, hardest, greenest nephrite yet discovered” (Ward 1998). The largest discovery was the ‘Polar Pride’, an 18 tonne gem-quality boulder which was discovered by Kirk Makepeace and was later sold to the Wat Dhammongkol Monastery which carved it into the Jade Buddha for Universal Peace which has toured the world and attracted over 7.5 million visitors.