|JADE, a gem variety of both Jadeite and Nephrite|
VARIETY OF: both jadeite and nephrite
USES: Gemstone and ornamental stone.
COLOR: shades of emerald green as well as white, gray, yellow, orange and violet.
INDEX OF REFRACTION: is approximately 1.66 (jadeite) and 1.62 (nephrite)
HARDNESS: 6.5 - 7
CLEAVAGE: does not apply due to massive nature of jade
CRYSTAL SYSTEM: monoclinic
Jade is a name that was applied to ornamental stones that were being brought to Europe from China and Central America.
It wasn't until 1863 that it was realized that the name "Jade" was being applied to two different minerals.
The two minerals are both exquisite for the purposes that jade is put to task and are hard to distinguish from each other.
So what to do?
Leave it alone and call them both Jade!Jadeite is almost never found in individual crystals and is composed of microscopic interlocking crystals that produce a very tough material.
Nephrite is actually not a mineral, but a variety of the mineral
The nephrite variety is composed of fibrous crystals inter-twinned in a tough compact mass.
Other actinolite varieties are quite different from nephrite.
The toughness of jade is remarkable.
It has a strength greater than steel and was put to work by many early civilizations for axes, knives and weapons.
It was later that jade became a symbolic stone used in ornaments and other religious artifacts during the eons.
Today jade is still valued for its beauty.
Its many colors are appreciated, but it's the emerald green color (that jadeite produces so well) that is highly sought after by artwork collectors.
This emerald green jade called "Imperial Jade" is colored by chromium.
Other colors are influenced by iron (green and brown) and manganese is thought to produce the violet colors.
Nephrite is usually only green and creamy white, while jadeite can have the full range of jade's colors.