Jade, a fascinating rock

One of the differences between jade and stone is that jade is delicate to the touch, warm and firm, translucent and lustrous like grease, whereas stone is rough and dry, without luster and also generally opaque.

- min of reading

Céramique de chine couleur de jade | Théières à la folie

Summary :

The concept of jade has never been defined very strictly. There is a wide variety of minerals known as jade in China. Generally speaking, minerals that are aesthetically pleasing, hard, and hot can be called jade. And at the same time, there are others that fit the usual definition of jade very well but are not called jade, such as that pretty stone known as agate. Chinese jade culture has a long history of over 10,000 years. The ancients were superstitious and believed that jade had a protective effect against evil spirits. Jade was very precious, they used it to make ritual objects such as statuettes, cups, plates, decorative objects, bracelets, hairpins, rings and necklaces. Moreover, jade was so strong that it could withstand hammer blows, a property that even diamond could not match. China is the oldest and most widespread country in the world for the extraction and use of jade. Jade is one of the noblest minerals. Jade is rich in many elements, such as zinc, iron, copper, manganese, magnesium, cobalt, selenium, chromium, titanium, lithium, calcium, potassium, and sodium. The main colors of nephrite are white jade, yellow jade, greenish white jade, purple jade, ink jade, jasper, green jade and red jade. Yellow Nephrite is best, Purple Nephrite is more of a pale pink, Ink Nephrite is a jade with black flecks on the jasper, and Green Nephrite is a dull, greenish white jade. White jade is most of the time the best. There are many shades of green jade, from light green to dark green, turquoise, gray-green, dark gray-green and emerald green. Green jade is the most common jade, and its gemstone has increased in value over the years. White jade varies from white to greenish white. White jade is a superior quality. Green-white jade is white in color, with faint hints of green, gray-green in the white, and is commonly found in onion-white, pink-green, and gray-white. It is a variety of transition between white jade and green jade. Topaz ranges from pale yellow to deep yellow, chestnut yellow, sunflower yellow, egg yolk and tiger skin yellow which is very rare, and has only been seen occasionally over the thousands of years of exploration of the jade. The most famous jade in China is Hetian jade from Xinjiang, then there is Dushan jade from Henan province, Xiuyan jade from Liaoning province and Lantian jade from Shaanxi province which are among the four jades. the most famous in China. The quality of jade is generally judged on five aspects: texture, hardness, transparency, specific gravity and color. Jade texture refers to the degree of fineness and warmth of jade. One of the differences between jade and stone is that jade is delicate to the touch, warm and firm, translucent and lustrous like grease, whereas stone is rough and dry, without luster and also generally opaque. Hardness refers to jade's ability to resist external forces such as pressure, carving, and grinding. The higher the hardness, the more difficult the processing, and the better the quality of the jade. The hardness of exit can be determined by testing the internal crystal structure of the stone using a special instrument. Its hardness is higher than that of copper and lower than that of glass.An alternative to jade then appeared, made from jade powder synthesized by artificial high pressure, which resembles Hetian jade in color and hardness, and must be studied with special care to identify it.
A quick note about this, at the Jingdezhen International Ceramics Fair, a new type of porcelain was praised by experts and visitors for its jade-like softness and translucency. It was developed by the jingdezhen porcelain and jade research institute. The director of the institute Huang Sheming explains: the clay is mixed with jade powder, the ceramists have created a jade porcelain, similar to jade. “We took 10 years to develop such a material,” they say. Real jade cannot be painted because it cannot withstand high temperatures to fix colors. One can only engrave on jade objects, while jade porcelain allowed this.

Leave a comment