Nephrite is a variety of the calcium and magnesium-rich amphibole mineral actinolite (aggregates of which also make up one form of asbestos). The chemical formula for nephrite is Ca2(Mg, Fe)5Si8O22(OH)It is one of two different mineral species called jade. The other mineral species known as jade is jadeite, which is a variety of pyroxene. While nephrite jade possess mainly grays and greens (and occasionally yellows, browns or whites), jadeite jade, which is rarer, can also contain blacks, reds, pinks and violets. Nephrite jade is an ornamental stone, used in carvings, beads, or cabochon cut gemstones.
Nephrite can be found in a translucent white to very light yellow form which is known in China as mutton fat jade, in an opaque white to very light brown or gray which is known as chicken bone jade,as well as in a variety of green colours. Canada is the principal source of modern lapidary nephrite. Nephrite jade was used mostly in pre-1800 China as well as in New Zealand, the Pacific Coast and Atlantic Coasts of North America, Neolithic Europe, and southeast Asia. (Source:Jade Wiki)
