Hetian Jade is nephrite, commonly known as genuine Jade. In a narrow sense, Jade generally refers to Hetian Jade in Xinjiang. The English name is Nephrite. The chemical composition is hydrated calcium magnesium silicate, and the chemical formula is Ca: Mgs (OH) Z (Si4011) 2. The hardness is 6-6.5 and the density is 2.96-3.17. Hetian Jade, Lantian Jade of Shaanxi Province, Nanyang Jade of Henan Province, Jiuquan Jade of Gansu Province and Uranium Rock Jade of Liaoning Province are also known as five famous Jades in China.
Jade culture is one of the oldest and most representative ancient cultures of Oriental civilization. Jade represents noble morality, beauty and dignity. At the end of October 2003, after several years of selection of China's "National Jade", Hetian Jade in Xinjiang was named "Meiyu" and was officially named "National Jade" by China Gem and Jade Association.
Hetian Jade is named after its origin and has undergone an evolutionary process. As early as the Neolithic Age, the ancestors of the Kunlun Mountains discovered the Hetian Jade, and as a treasure and a medium of friendship, they transported and exchanged it to the East and the West, forming the "Jade Road" of the oldest transport channel of Hetian Jade in China, which was the predecessor of the later "Silk Road". During the Warring States Period, Hetian Jade was called "Yushi Jade". Qin Dynasty is also known as "Kunshan Jade", and later called "Yutian Jade".
Qin Shihuang began to practice imperial system in China until the Qing Dynasty, when Hetian Jade became imperial Jade. Most of the palace jades are made of Hetian Jade. Especially the jade seals symbolizing imperial power are made of jade, most of which are Hetian jade.
It is found that the earliest jades made of Hetian Jade came from Fuhao Tomb in Yin Ruins. After the Spring and Autumn Period and the Warring States Period, Hetian Jade gradually became the main jade material, all of which were collected materials. From the Qing Dynasty, mountain materials were mined.
From the viewpoint of geological science, Hetian Jade has a clear scientific meaning. It refers to a series of jades, such as white, topaz, sapphire and moyu, which are distributed in Kunlun Mountains of China and formed by the contact metasomatism of magnesia marble and intermediate-acid magma, especially white jade. Its origin and variety occupy a unique position in the world nephrite and have typical significance. The variety of nephrite in the world is single, and most of them are jasper, while Hetian Jade has many varieties, and there are rare white jades in the world. Jade quality ranks the top of nephrite in the world. The world deposit is of serpentinite type, which is related to ultrabasic rocks, while the Hetian Jade deposit is of non-serpentinite type. Its genesis is not regional metamorphism, but typical contact metasomatism, which are very unique in the world.
Place of Origin
Hetian Jade is distributed in the northern slope of Kunlun Mountains in Shache, Kashgar, Kurgan, Hetian, Yutan and Qiemo County, which stretches 1500 kilometers. There are nine producing areas. The mineral composition of Hetian Jade is mainly tremolite-actinolite, and contains trace diopside, serpentine, graphite, magnet and other minerals, forming white, green, black, and other different colors. Most of them are monochrome and a few are variegated. Jade is translucent and glossy after polishing.
Hotan Jade is found in rocks between 3500 and 5000 meters above sea level. After a long period of differentiation and fragmentation, the fragments of different sizes collapsed on the hillside, and then washed into the river by rainwater. When the river dries up in autumn, collecting jade blocks in the riverbed is called seed jade, and mining in the strata is called mountain material. It is found that the earliest jades made of Hetian Jade came from Fuhao Tomb in Yin Ruins. After the Spring and Autumn Period and the Warring States Period, Hetian Jade became the main jade material, collecting seed materials, and mining mountain materials from the Qing Dynasty. Dayu Zhishui Jade Mountain in the Qianlong Period of Qing Dynasty weighed more than 5000 kilograms, i.e. from Maileta Mountain.
Hetian jade can be divided into three types according to its origin: sub-material, landscape and mountain material.
1. Denim. Zier Jade, also known as Zier Jade, refers to the original ore denudation was washed out and carried to the river. It distributes in the riverbed and the riverbanks on both sides. Jade is bare or buried underground. It is characterized by small size, often egg type, smooth surface because of its long history, long-term water erosion, transportation, sorting, to the dregs, retain the essence. Or buried in the earth, several different pits, sucking the essence of the earth. So Ziyu is generally better in texture, because it sucks and drinks sufficiently and is extremely warm and moist. Ziyu can be divided into nude Ziyu and leather Ziyu. Nude jade is generally picked from river water, while skin color jade is generally picked from the soil of the river bed. Therefore, the age of skin-colored Ziyu is even longer. Some precious varieties of skin-colored ziyu, such as jujube red, black skin, autumn pear yellow, yellow wax skin, golden spray, tiger skin and so on, all come from skin-colored ziyu.
2. Mountains and rivers. The name is named by the artists who collect and cut jade. It refers to the formation of primary jade ore by weathering and collapse, and by the impact of river water to the upper and middle reaches of the river. Landscape is characterized by its proximity to primary minerals, larger fragmentation, slightly rounded edges and corners, smoother surface, younger age and younger than Ziyu.
3. Mountain material. Also known as Shanyu, or Gaibaoyu, refers to the primary minerals produced in the mountains. The characteristics of mountain materials are different fragmentation, angular shape, uneven good and bad, often inferior to landscape and Ziyu in quality. Strictly speaking, the mountain material has not been baptized by nature, and has not been saturated with the essence of the universe. It should be called Jade, and it should not be called Jade.