First of all, there may be a lot of people out there who wonder whether the right term used is Jadeite or Jade.
Please allow us brief the history of Jade. Jade is one of the oldest ornamental and tooling materials dating back as far as 5,000 years ago, even before metal age in human history. The term ‘jade’ was used loosely to represent a wide range of materials used for carving and tooling.
Jade has a rich history in the Chinese culture, both for its virtues and mystical power. Confucius praised jade for being a 'righteous' and 'knowledge' stone; the Chinese saying "one without wearing a jade is not a gentleman" says it all. Chinese also believe that jade will reflect the wearer's luck and ward off any bad encounters.
The Chinese are not alone in this; at the other end of the World, ancient Central American Indian wore jade around their waists with the belief of relieving pain and preventing any kidney diseases. The name ‘Jade’ came about later when the Spanish name it ‘Piedra de jada’ which means ‘stone of the flanks’, believed to be protective against kidney diseases.
Prior to the late 18th century, jade used in China was mainly nephrite jade. In spite of being a small quantity of jadeite reportedly existed as early as the ‘Song’ dynasty, it was not until during the ‘Qian Long’ rule when China expanded its territory into Northern Myanmar (former Burma) that jadeite jade gained its popularity.
In 1863, French mineralogist, Alexis Damour, classified the two different types of jade material into ‘Nephrite’ and ‘Jadeite’. So the right trade term is Jadeite or Jadeite Jade.
Properties of Jadeite
Chemical composition: NaAlSi2O6
Crystal system: Monoclinic
Structure: Interlocking granular
Refractive Index: 1.66 spot
Specific gravity: 3.3 - 3.5
Hardness: 6.5 - 7
Colors: colorless, white, green, red, purple, yellow, brown, black
Melting point: 900 deg C - 1000 deg C