Nephrite stone is a rock, one of the three called jade, along with jadeite and kosmochlor: these three minerals have long been mixed up as they have similar appearance and properties, although their chemical composition is not the same. It was widely used as early as the Neolithic period for the design of tools, jewellery and ornamental objects. It enjoys a long history in 3 areas: Europe, China and New Zealand. Archaeological research has also shown its use on the coasts of North America and in Southeast Asia. In Europe, it was first assimilated to jasper or chalcedony. Under the influence of the Spaniards who traded the “piedra de ijada” which translates as “kidney stone”, the French called it “pierre de l’éjade” to gradually move to its current name. This Spanish denomination comes from their knowledge of its medical use by the peoples of Central America to treat kidney ailments. It appears under this name, but also under the name “nephrite” in the General Dictionary in 1667. Nephrite stone was already recognized for its action on renal diseases. It was distinguished from jadeite in 1863 by the French scientist Alexis Darmour. He was not a university-trained geologist but a self-taught man with a passion for the chemical analysis of minerals. Currently, it is sometimes used in jewellery to replace jadeite, which is much rarer.
In China, it has been known and used since the Neolithic period. Its deposits, now exhausted, were located in the Ningshao region, in the YangtzeKiang delta, in the Khotan region of Xinjiang in Liaoning Province and in Inner Mongolia. The deposits of white and greenish nephrite stones take the form of small veins. They are also carried by rivers, including the Yarkand, Yurungkash, “White Jade River” and Karakash, “Black Jade River”. The kingdom of Khotan paid an annual tribute to Imperial China for this rock, which was worth more than gold.
Indeed, for the Chinese it embodied beauty and preciousness. It is considered the most perfect representation of the principle of Yang in Taoism, Yang being the energy that dispenses life and represents masculinity. From prehistoric times, it was considered a rock with magical properties. The Chinese culture in the following eras confirmed this fascination for this mineral to which extraordinary properties and symbolism were lent. A grasshopper carved from this rock was placed in the mouths of the deceased to guarantee them eternal life and resurrection in the afterlife. It was supposed to protect the body from putrefaction. It embodies virtue, purity, tranquillity, reserve and elegance. Legends have also given an important place to this mineral, including the legend of the creation of mankind and the legend of Pangu. It was therefore mainly used to carve utilitarian and ceremonial objects: interior decoration objects, funerary costumes, emblems of various shapes used during ceremonies in the presence of the Emperor. The Emperor was required to carry a sceptre carved from this rock (Ruyi) during ceremonies. It was considered to be the “imperial stone” and is closely associated with the Emperor and imperial power. Like the Emperor, it is considered an intermediary between the earthly and celestial worlds. It aroused this enduring fascination among the Chinese because of its rarity and relative hardness, for which it symbolises both temporal and spiritual power. Its trade is an imperial monopoly. The Emperor was the only one who could use tablets carved from this rock to write. It was a symbol of power and prestige. Its function was to indicate the rank of a Chinese dignitary or noble official by adorning his belt. Similarly, the princes of the imperial court were each given a tablet carved from this rock with special motifs to identify their rank.
However, the Chinese deposits dried up and the Chinese turned to importing minerals from Turkestan, using the Silk Road. This trade route allowed trade between the Middle East, India and China through the passage of caravans. The caravans carried not only silk, but also Turkestan nephrite stone, tea and porcelain. Two routes were used, which went around the arid and dangerous Taklamakan desert to the north or south. They were punctuated by oases, crossroads of trade and important cultural and religious exchanges, whose function was to provide rest and new animals for the caravans. Nephrite trade was the most prized of the Chinese and justified the continuation of trade via the Silk Road until the 18th century.
In New Zealand, this rock holds a special place in Maori culture. It is known as “pounamu” and is considered a treasure. It is protected by the Treaty of Waitangi: its extraction is strictly limited. The Maori use it to make weapons such as meres (which look like short masses), ornaments, such as the Hei-tiki on necklaces, but also tools because iron is not present on the island. The Maori consider that they have their own “mana”, which means “power” or “prestige”; they are transmitted in families as heritage goods and could be offered to seal agreements.
Nephrite stone is either translucent, in which case its colour is white or slightly yellow (variety called “sheep fat” in China), or more opaque, in which case its colour is white, slightly brown or grey (variety called “chicken bone” in China) and green in all its shades. Some greens are pale, others very dark, even blue-green.
It is a rock composed of actinote, a ferromagnesian mineral of the silicate family. This mineral is composed of magnesium and calcium silicate. It is the iron contained in this mineral that gives it its green colour. Its colour looks light when the percentage of iron is low and dark when the percentage of iron is high. Its hardness is rather average, contrary to the appreciation that the Chinese have made of it: it is 5.5 to 6 on the Mohs scale. This indicates that it can be scratched by metals such as the blade of a pocket knife. Its weight is rather high and also varies according to the proportion of iron. The actinote in this rock is produced by metamorphism (transformation of a rock under particular conditions of temperature and pressure) or comes from volcanic rocks. Canada is currently the largest extractor of this rock. Other deposits are mined in China, Russia and New Zealand.
This mineral symbolizes honesty, especially in a context of power, but also self-control. It has the property of providing its wearer with more tolerance and objectivity in his or her judgment towards others. Justice and morality are the qualities that this mineral requires. It thus increases the level of consciousness by fighting against the inadequacy of moral judgment. It is ideal for people working in the field of mediation, negotiation, where the search for balance is constant. It also allows the wearer to confront reality in a responsible manner.
Its presence stimulates appeasement by regulating the chronic nervousness and instability of those who wear it. It is particularly effective in connection with the heart chakra (the 4th chakra) and the 3rd eye chakra (6th chakra).
The main physical properties of this rock are fever and headache. It helps in the treatment of all chronic physical ailments of nervous origin, especially upon diagnosis of herpetic lesions, skin disorders related to nervousness. Lithotherapy is always practiced in addition to medication and should not replace a medical diagnosis and prescription.
It is very well known for its action on kidney disorders and on the adrenal glands. Its name comes from the Greek “nephros”, which means “kidneys”. In the medical field, acute tubulo-interstitial nephritis is an infection of part of the kidney. The use of this mineral favours the elimination of kidney stones through urine, calms cystitis (or acute urinary infections, which may worsen into pyelonephritis) and urinary incontinence, always, of course, in parallel with treatment with prescribed medication.