Not sure how many know this.
Some nz Greenstone is actually imported from canada & other places!
Also some greenstone is treated:
jadeite has not been treated in any way except surface waxing.
treatment involves exposing a promising but stained piece of jadeite to chemical bleaches and/or acids and impregnating it with a clear polymer resin. This results in a significant improvement of transparency and colour of the material.
Currently, infrared spectroscopy is the most accurate test for the detection of polymer in
jade has been artificially stained or dyed. The effects are somewhat uncontrollable and may result in a dull brown. In any case, translucency is usually lost.
B+C jade is a combination of B and C: it has been both impregnated and artificially stained.
jade refers to a composite stone such as a doublet comprising a jade top with a plastic backing.
Here is a funny little doco on Chinese Jade hunters