A total of 380 pieces (sets) of jade were excavated from the tomb of prince of Yuguo (M2011), of which some of the jades unearthed were more seriously bleached, and the jade showed a more transparent, translucent, micro-transparent, opaque and other states after being qined. The Museum of the State of China and the China University of Geosciences (Wuhan) cooperated to conduct scientific detection and analysis of the jade of the M2011 tomb, and carried out non-destructive identification and analysis with infrared spectrometer, X-ray diffraction instrument, laser Raman spectrometer and other instruments, and observed, identified and studied the gemological parameters such as the name, classification, color, color, luster, transparency and density of the excavated jade, the structure and texture characteristics of the jade, as well as the jade ornamentation and production process.
Here are 23 pieces (sets) of more typical jade albinism and qin phenomenon, and the situation of these jades is introduced as follows.
From these jades, it can be seen that the jade has been subjected to different degrees of white Qin phenomenon, which is also commonly known as calcification, which means that the jade is subjected to some white powder in the surface or pores of the vessel after long-term weathering, or a layer of white soft inclusion is generated (after the glittering jade is whitened, the specific gravity often becomes lighter and the hardness decreases). For the phenomenon of bleaching of jade, Qing Dynasty scholars have studied it in more detail and recorded it more abundantly, such as Xu Shouji of the Qing Dynasty wrote in the "Jade Genealogy Compilation": "Jade is attached to things in the soil for a long time. The yellow ones are loess Qin and rosin Qin; the white ones are lime Qin; the green ones are qingtu Qin and copper Qingqin; the green ones are patina Qin; and the black ones are mercury Qin. Liu Zifen, a scholar of the Republic of China, wrote in his book "Ancient Jade Examination": "Jade has two kinds of soft and hard, both containing lime and mercury. ...... Newly unearthed ancient jade, its surface is often white, such as sticky lime, but after being manipulated by people, the body regenerates white spots, such as slag, that is, the lime dissolved in its body. "As for the causes of jade bleaching, Qing Dynasty scholars believe that because the jade has been in the soil for a long time, the lime in the ground is soaked on the jade, so the jade bleaching is formed. Scholars in the Republic of China believe that the jade itself contains lime caused by bleaching.
With the development of science and technology, modern science and technology (such as infrared spectrometer, X-ray diffractometer, laser Raman spectrometer, etc.) are applied to the study of jade, and people have a scientific understanding of the phenomenon of jade bleaching. First of all, the jade bleaching phenomenon is formed after the jade is buried in the soil, which can change some of the original physical properties of the jade, such as color, transparency, hardness, etc.; the discovery of the calcification phenomenon shows that the bleaching phenomenon can also change some of the original chemical properties of the jade, such as the sedimentary infiltration of calcium salt components. Therefore, when conducting archaeological research on jade cultural relics, special attention should be paid to the effective identification and information extraction of the original appearance of jade materials, avoiding weathered areas. The original appearance of the whole albino jade can be judged by means of transmitted light, and the original appearance of the serious overall albino jade needs to be assisted by other jade excavated from the same tomb. Secondly, previous studies have confirmed that many albino jade objects that are loose in the qin part of the jade are already fragile cultural relics, so they need rescue reinforcement and restoration and preventive suitable environment.
From the naked eye observation, it can be seen that the 23 pieces (sets) of jade excavated from the tomb of the prince are quite different in the degree of qin and the characteristics of qin. Mildly qined jade can directly identify the original color of jade with the naked eye, jade exhibits greasy luster, micro-transparent - translucent optical characteristics, moderate and severely qined jade its original jade characteristics are destroyed, the gloss, transparency and density of these jades have decreased to varying degrees, manifested as waxy luster - earthy luster, micro-transparent - opaque. These excavated jades were tested with infrared spectrometers, X-ray diffractometers, laser Raman spectrometers and other instruments, and the results were obtained: 20 of the 23 pieces (sets) of jade were nephrite, which were divided into two kinds: white jade and green white jade; and the test results of 2 pieces of jade were fine sandstone and 1 was Dali rock.
▲Fishtail dragon shaped jade pendant
Jade albinism phenomenon caused by the internal structure of jade loose, jade albinism appears dotted and flaky distribution of albinism phenomenon, there are also jade whole body bleaching phenomenon, and jade calcification areas with serious hand touch there are falling powder particles, which causes great harm to jade, so the albinism and calcification of serious jade should be effectively protected, and the preservation environment of jade should also be treated accordingly to achieve the ideal effect of protecting jade.
Yu Jue observes with the naked eye that it is waxy - earthy luster, slightly transparent - opaque (translucent under strong light), cryptocrystalline dense - grainy sense is not dense, body-like Qin, yellow-white Qin, the naked eye can distinguish the blue-white natural color and yellow-white Qin color. The jade pipe body is two bands of Qin that penetrate into the interior, which is different from other jade qin directions, so the luster and transparency are better. Under the microscope, the unqined part is bluish-white and transparent, while the white qined part is opaque, and the earthy yellow qined part is translucent.
The fishtail dragon-shaped jade pendant is waxy - earthy luster, opaque, body-like Qin, Qin color is white, earthy yellow and yellow-brown, some retain a cryptocrystalline dense structure, some are grainy due to loose Qin. The unpopular part of the fishtail dragon-shaped jade pendant is bluish-white, the white qin is translucent -opaque under transmitted light, the earth yellow qin is translucent, and the yellow-brown qin is opaque. Combined with the above jade situation, the qin will change the color of the jade, so that its luster and transparency decrease, the same piece of jade can have a variety of Qin colors, different parts of the degree of qin.
Microscopic observation of the degree of qin of the winding tail double dragon pattern, Qin color has the law of distribution along the ornament, indicating that the jade carving process will destroy the surface structure of the jade, resulting in it being more susceptible to Qin, under the microscope, the winding tail double dragon pattern contains a blocky blue-white substance, which should be a tremolite with large crystalline particles, which is lighter than the degree of acceptance of the surrounding cryptocrystalline tremolite, indicating that the degree of good crystallization of the same substance in the same environment is relatively weak.
▲ Yu Jue
▲ Panlong-shaped jade pendant
The results of the scientific analysis of jade from Tomb M2011 show that: First, the material of the jade is different, the degree of bleaching is different, and the bleaching phenomenon is from weak to strong tremolite, serpentine and fine sandstone. The jade ring belongs to tremolite, and the albinism phenomenon is rare, only on the side of the jade ring, there are some dot-like albino spots, and the albino spots only float on the surface, and do not penetrate deep into the jade body. The humanoid pendant belongs to the serpentine, and the metal cation Mg element in the jade crystal has been lost a lot, so that the percentage content of SiO2 exceeds the normal value, and the jade is seriously albinized, and its body only retains the fibrous serpentine crystal form. The jade pipe is Dali rock, all of which are grayish white, the jade is seriously affected, the texture is rough, and the surface of the jade is touched by hand, and the surface has powder-like particles, and it is easy to fall off.
Second, the jade material is the same, but the degree of jade bleaching varies with the complexity of the jade technique and process. Winding tail double dragon pattern and jade pipe are cryptocrystalline dense blue jade, jade pipe due to the simple production process, do not need to carve many ornaments, the surface polishing fine polishing, therefore, the albinism phenomenon of the jade pipe is the two bands of Qin that penetrate into the interior, which is different from the direction of qin of other jade objects, so the luster and transparency are better.
▲Left: Jade Pipe; Right: Jade Man
The ratio of jade to stone used in different levels of tombs and the advantages and disadvantages of jade are different, and the higher the level of tombs, the higher the proportion of jade, and the better the texture and processing of nephrite. M2011 Prince Tomb is a Qiding tomb, most of the excavated jade is white jade and green white jade nephrite, but also confirms the owner's high status level, but also shows that jade was already a symbol of rank, power, etiquette, and wealth at that time, which also corroborates the authenticity of the "Zhou Li Kao Gong Ji • Jade People" grade jade.
Original title: Analysis of the phenomenon of "albinism" of jade excavated from the tomb of prince Of Yuguo
Author: Jiao Jing
Author Affilications: Gyalpo Museum
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