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What is Jade?
Strictly speaking, Jade can only be used to refer to either Nephrite or Jadeite minerals. Each of the minerals is a member of a complex chemical composite, and its properties vary substantially through the substitution of different metal ions in its structure.
Nephrite belongs to the Amphibole group, consisting of two different silicate minerals with a monoclinic crystal system. These two minerals, tremolite and actinolite, differ essentially
in the ratio of magnesium to iron. High quality nephrite is formed through the process of metamorphism during which its mineral structures are altered by high temperature and high pressure. Tremolite belongs to the group Ca2Mg5Si8O22(OH)2, and Jade under this group tends to be whiter; those of highest quality may reach the ‘mutton-fat’ grade. Actinolite belongs to the group Ca2(MgFe)5Si8O22(OH)2,and Jade under this group tends to have a greyish green tone.
Jadeite, a sodium aluminium silicate, is a member of the pyroxene group of minerals, NaA1Si2O. Jade quality starts to deteriorate when Calcium, Magnesium and Iron are introduced in the composition. Similar to Nephrite, Jadeite is formed under extremely high temperature and pressure during the metamorphical process beyond 30Km into the earth’s crust.
Nephrite & Jadeite
It is commonly accepted that the Mohr hardness of Nephrite and Jadeite is 6-6.5 and 6.5-7 respectively. Due to this aspect, in 1925, Japanese since then classified Nephrite as ‘soft Jade’ and Jadeite as ‘hard Jade’.
However, this is technically wrong! In 1978, Taiwanese Professor Tan Li Ping pointed out that Mohr hardness is a simple and crude test that needs to be replaced by more accurate Vickers Hardness test method. Using this Vickers hardness test method, Prof Tan discovered that the so-called ‘soft Jade’ Nephrite, in fact is harder than the ‘hard Jade’, Jadeite.
Researchers found out that by adopting the Vickers method and converting back to Mohr Hardness scale, Nephrite achieved a Mohr hardness of between 5.8-7.1; the highly prized Khotan Nephrite as well as the New Zealand Nephrite also attained hardness of 6.5-7. Hence, the terms ‘hard Jade’ and ‘soft Jade’ for classifying Jadeite and Nephrite are misleading and outdated; they ought to be discontinued.
Both Nephrite and Jadeite are very dense minerals. Under a microscope, Nephrite has a fibrous structure and Jadeite is more crystalline; that explains why Nephrite has a higher tenacity than Jadeite. The basic colors of Nephrite are white, green and yellow. However, when Iron starts to replace Magnesium during the chemical composition, its colors will vary between celadon, greenish-yellow and yellowish-white; other colors like red and black can also be found. The visual appearance of Nephrite is translucent with a soapy appearance, and Jadeite is having a vitreous luster. Gem quality Jadeite can only be found at the border of China Yunan province and Burma; hence Jadeite is sometimes referred to as ‘Burmese Jade’. The colors of Jadeite vary from white, grey, green, violet to red; with the imperial green as the most highly prized and sought after color.
Chinese Jade I : Neolithic Period
The usage of Jade in China history goes back to as early as the Neolithic period, whereby tools and weapons were made in jade and other hard stones. These jade tools were plain and mainly utilitarian.
Discs or ‘bi’ in the HongShan culture are usually rectangular with rounded corners and most of them had two holes at the top for suspension. As mentioned, numerous discs were found in HongShan tombs, carefully laid on the bodies of the dead. No clear evidence has shown any specific notion of these discs. Certain believes from the HongShan culture can be seen transferred to the later Neolithic period, the LiangZhu culture(4000BC-2500BC) where discs were also seen in LiangZhu tombs. These discs are similar to that of the HongShan’s disc with a small central hole proportionally in size with its overall circular shape.
The Hongshan culture (4000BC-2500BC) adopted a much more sophisticated society. Jades were widely used as burial goods in ancient tombs. To the HongShan people, jades were of enormous importance, and were often the sole burial items during those times. The majority jade types are discs with holes, known as ‘bi’.
In some discovered tombs, as many as nine ‘bi’ were found aligning with the limbs of the body. Other important jade types were axes, c-dragons or pig-dragon, abstract shapes of eagles(birds) or aliens.
HongShan jades illustrated an extraordinary command of material and techniques of carving. These jade ‘bi’ or dics were worked with great attention to detail and enormous subtlety of its surfaces. The level of craftsmanship during this period is also very sophisticated, emphasizing on simple shapes and forms. This can be seen on pig dragons whereby the stone and the techniques are distinctive and do not occur in other cultures.
During the LiangZhu culture, much more advanced and highly skilled carving techniques can be seen from carvings of massive cong from large blocks of jades to fine incised lines of details found on beads and ornaments.
‘Cong’ is a jade piece of a square outer section with a circular hole, tapering from a wider x-section on the top to a slightly smaller x-section at the bottom. ‘Cong’ is one of the principal jade types of the LiangZhu culture. A typical motif of a mythical beast face can be seen widely on Liangzhu jade congs, ornaments, plaques and beads.
Jades were essential to both HongShan and LiangZhu societies, however, the manner in which they were made suggests that they were differently deployed. We can see that most of the HongShan jades could be worn, while the LiangZhu jades were mostly ornamental. ‘Bi’ and ‘cong’ neither show obvious utilitarian usage nor decorative functions, therefore, such jades were treated as a different category, described as ritual jades.
Chinese Jade II : Early Dynasty
Chinese civilization, as described in mythology, begins with Pangu (盘古), the creator of the universe, and a succession of legendary sage-emperors and culture heroes (among them are Huang Di 黄帝, Yao 尧 , and Shun 舜) who taught the ancient Chinese to communicate and to find food, clothing, and shelter .
The first prehistoric dynasty is said to be ‘Xia’ (夏) (2000BC-1600BC), followed by ‘Shang’ (商) dynasty (1600BC-1050BC) and ‘Zhou’ (周) dynasty (1050BC-221BC).
Until scientific excavations were made at early bronze-age sites at Anyang (安阳), Henan (河南) Province, in 1928, Xia dynasty had remained as a myth with no historical evidence on its existence. Xia Dynasty resumed hereditary realm from the legendary Yellow Emperor times, and began the period of a family or a clan controlling the nation. It was also during this period that the Chinese civilization developed a ruling government and harsh punishment for legal violations . Jades found from the excavated sites, presumed to belong to Xia dynasty, were mainly jade weapons. To Chinese, Jade is a symbol of ‘power’ and ‘status’, and using jade as weapons were meant to send the signal of military power during that time.
The earliest written archaeological records only start to exist during the Shang dynasty in the language we now known as Chinese. Shang and Zhou dynasties’ craftsmen had full command of the artistic and technical knowledge developed from the late Neolithic cultures, which had a jade usage tradition.
Written records and archaeological evidence also proved that jades were used in sacrificial offerings to gods and ancestors, in burial rites, for recording treaties between states, and in formal ceremonies at the courts of kings. And jade carvings depicting birds were widely used during this period.
The Shang dynasty’s jade carving design consist of mainly double incised lines of meander patterns, illustrating the artistic and technical knowledge of the Shangs.
Chinese Jade III : Imperial China
Archeological findings indicated that burial jades were crucial to the after-life of the elites. This belief reached its peak during the Han dynasty, where jade were believed to even presumed the body of the dead. Jade carvings on mythical beasts and highly elaborated hollowed bi disc were widely used.
During the Tang Dynasty, Buddhism flourished and jade artistry suffered a decline. However, during this period,jade remained a previleage for the selected elites. This can be seen in the Tang Shi Lu (Annals of the Tang Dynasty), which denoted as follows :
‘Civil and military officials from the 3 rd rank and above should wear gold belts with 13 pieces of jade; those of the 4 th rank will wear gold belts with 11 pieces of jades and 5 th rank with 10 pieces of jade and only rhinoceros horn materials of 9 pieces are deserted for 6 th rank and below…..’ in descending order of seniority.
Song dynasty was an era where much emphasized had been placed on scholars and poets. Therefore, scenery and poems subjects were widely used in jade carvings. Chinese idioms related to auspicious meanings were also carved into ornaments or figurines, and this practice was passed down even till to-date.
The Yuan Dynasty, which lasted from 1279-1368 A.D., was the first of only two times that the entire area of China was ruled by non-Hans, in this case, the Mongolians. During this period, they were the strongest military forces in the world. Hence, eagles and hunting scenes commonly related to Mongolian livelyhood, were used as subjects in jades.
Han dynasty carving patterns, followed closely the styles from the Eastern Zhou dynasty with some differences; It transformed its style from a formal elegant into a more flamboyant and realistic manner; It modified the symmetrical carvings skills from the Zhou dynasty into an unsymmetrical style; and further improved the jade ‘open-work’ technique to a much higher level.
Ever since the Tang period to the Qing dynasty, jade were widely used for personal ornaments such as pendants, belts, dress and hair ornaments, jewelry and small accessories for hanging round the person.
During this period, jade was obviously used for personal display and appreciation rather than for burial or ceremonial purposes.
Flying female deity; dancers with varies musical instruments; and male westerners (胡人) figurines were widely seen on jades belonging to the Tang dynasty.
Early Ming decorative arts inherited the richly eclectic legacy of the Mongolian Yuan dynasty, which included both regional Chinese traditions and foreign influences.
From the Tang period to the Ming dynasty, there was a significant diversion of preference to gold than jade, causing an obvious decline in jade craftsmanship.
The Qing Dynasty was the second time that the whole of China was ruled by foreigners, the Manchus. The reigns of the first three emperors of this dynasty were a time of peace and prosperity for China. These three rulers provided strong leadership for 133 years; they were the Emperor Kangxi, Emperor Yongzheng. and Emperor Qianlong.
During the reign of Qianlong, the borders of China were expanded to their greatest extent ever. It was during this time, the traditional source of nephrite, Xin Jiang 新疆 was annexed by Qianlong. His reign was the time of the greatest prosperity during the Qing Dynasty. He was a connoisseur of Chinese jade carvings, and set a very high standard towards jade appraisal which none other predecessors had ever achieved before.
For the purpose of imperial jade quality assurance, an imperial jade auditing unit was deliberately setup within the palace for the emperor’s easy command and control. Historical records show that Qianlong in fact personally appraised many spectacular jade pieces including categorizing their standings. However, Qianlong had a bad habit of engraving peoms on antique jade pieces, an act which till now, many scholars disapprove because it spoiled the original intended beauty.
Under a microscope, the crystalline structure of the jadeite was found.....
Appraisal cases : Dyed jadeite
Being a lover for jadeites, Mdm Lee bought this piece of three-colored jadeite pendant (as shown in Figure), claimed to be ‘fu-lu-shou’ by the seller. She was overjoyed as she bought it at a really good discounted price.
Few days after she came back to Singapore, we had a gathering and she happily showed me the pendant and asked me for my opinion. As usual, the piece of jade was left with me for a few days to check on.
First glance on the pendant gave me an impression that the piece was probably treated; later investigation proved me right. The jadeite color is unnatural; in layman’s term the color is ‘dead’ or lifeless.
Under a microscope, the crystalline structure of the jadeite was found loosely disoriented or damaged (as shown in fig ), an evidence denoting the jade had been soaked with concentrated acid for removal of unwanted oxidized color; unlike the unidirectional tightly packed alignment of crystal structure in a typical Grade A jadeite.
Furthermore, shining through the piece with a strong light source also revealed that the colors were found ‘floating’ or rather color concentration was diffused near the surface only; telltale indicating that the jade piece had undergone dyeing process.
With the help of reflected light source, multiple ‘spider webbed’ superficial crack lines could be seen on the surface; a result due to repeated acid soaking and dyeing process. At some location, color pigment concentration can even be seen ‘trapped’ at some crevices.
This pendant is most likely a ‘B+C’ jade. B (Bleaching) – due to soaking in concentrated acid for removal of iron stains with or without polymer injection for the purpose of bonding loosely packed crystals, and C (Colored) – due to artificial color impregnation.
This white jade plaque is made of nephrite material. Close examination revealed loosely packed structure and “water lines” inclusion
Appraisal cases : fake calcification
In the field of antique jade collection, not only must one be able to identify the different jade materials commonly used in various dynasties of ancient China, spotting tell-tales left behind by jade craftsmen is also very important in authenticating a piece of antique jade. In my early years of jade collection, armed with gemological knowledge, I was only able to identify the right choice of material; to tell whether a piece of jade is really that “old”, I still had a long way to go. As a result, I paid “school fees” to many dealers and learnt from the hard way.
This white jade plaque is made of nephrite material. Close examination revealed loosely packed structure and “water lines” inclusion, indicating that the nephrite is most likely to be of Qing Hai ‘清海’ origin rather than from Khotan of Xin Jiang ‘新疆和田’. The “dryness” effect in the blotched areas, simulating calcification process is artificially created by a form of heat treatment in order to make it looks old. The unusual flatness and glossy finished on the surface; with abrupt sharp turns in tight corners are tell-tales from modern high-speed tools.
Primitive tools usually leave behind undulating and blur-greasy polish, and the incised sharp turns are normally completed in stages and not at one go, as in this case. Therefore in my opinion, this is not a real antique piece, but a modern antique replica using nephrite material.
To reduce the mistakes and “school fees” that antique jade lovers might commit, I have summarized down the preventive steps to be followed, recommended by the book ‘gu yu tong lun’ 古玉通论 :
1. Jade type
3. Surface texture
4. Carving technique and style
5. Overall artistic design or theme
6. Background adopted pattern
Steps 1 to 4 will determine whether it is really an old piece, and 5 to 6 will help to estimate the era during the time when the jade was produced.
My advise to antique jade collectors is to own a few pieces of genuine antique pieces, study their characteristics; read lots of books to understand the trend and style during the different dynasties and periods; do some market research at jade markets in China or Taiwan to look at the latest advancement in ‘faking’ antique jades. Well, you may even able to find a piece of genuine antique jade at times.
The fun and excitement about collecting jade is to know more than the seller and to get an upper hand on bargaining, secondly, is one’s ‘jade- fate’, 玉缘 . To be able to find a particular piece of authentic jade, it’s not a matter of whether you can afford it or not, it’s whether you are fated to own it or even a chance to see it. So, at times, it’s still worthwhile to ‘bet’ on certain piece of jade. However, if it’s a wrong bet, simply take it as a learning fee. A piece of advise on betting on jade, especially at any jade market, it’s still better to bet on antique jades. For antique jade pieces, there are more tell-tail signs that current crafters are not capable in imitating. However, to be sure of the stone material, it is advisable to use some lab equipments or at least a 10x loupe.
Appraisal cases : white jade simulant
These two bangles were brought to me from a friend of mine, whom travels frequently to HongKong and Shanghai. He bought one of the bangle from a proper jade shop in shanghai and the other one from HongKong jade street during his recent overseas trip.
He is a jade lover, where jadeite and white nephrite jade being his favorite. He started collecting nephrite jades a few years back and understands the basic properties and characteristics of nephrite jade.
He had a pretty good “feeling” when holding onto the bangles; its luster, weight, feel and more importantly, the very good bargain (20% off normal jade bangles’ prices) he got from the seller urged him into buying it.
One fine morning, while I was about to leave home for an appointment, he brought in these two bangles. A quick glance on the bangles gave me an impression that the material was most probably QingHai white jade.
QingHai is a district in Tibet, where the mountains producing nephrite raw material is considered to be connected to the Kunlun mountains of Khotan region in Xin Jiang, the traditional supply source of Chinese nephrite.
Indeed, Qing Hai jade falls into the nephrite category since the physical properties e.g. specific gravity and refractive index, are within the nephrite range. However under close examination, the crystalline structure of QingHai type is rather loosely compacted comparing to Khotan jade. Besides, white QingHai jade usually comes in greyish hue with “water lines” inclusion. It was this “water lines” trademark that initially made me believed the bangles were originated from QingHai.
When I got home, I examined them under a microscope (40x) and found that the “water lines” trademark which I suspected to be, were in fact created by extremely fine bubbles! This aroused my suspicious and I validated further by checking on the specific gravity of the bangles; both yielded a result of 2.75, which fell short from 2.95 expected from typical nephrite. At this stage, I was quite sure that the bangles were not nephrite. But what are they?
Having S.G of 2.75 and Mohr’s hardness of less than 6.5, coupled with fake “water lines” due to swirling effect from fine bubbles, I suspect the bangles are definitely not made of nephrite material but some kind of artificial glass material. The swirling effect created by the fine bubbles is basically a “birth mark” of man-made glass, formed during continuous stirring stage in the manufacturing process.
A very simple but destructive method to check if a stone is Nephrite or not is by scratching it with a penknife. Nephrite material, having a Mohr hardness of 6.5 will not be scratched by a penknife, but other materials like glass, that has a hardness of about 5 can be scratched easily.
The prices of Nephrite is on a rising trend, and therefore, much more advanced methods are worth investing to deceive potential buyers. One common method of faking white jade is merely manufacturing look-alike white creamy glass; but one can still differentiate it with its light-weight feel. However, with the modern technology, higher lead content can be added to the glass to increase its density.
Therefore, my advice to jade lovers……only patronize reputable jewelry stores. Some unscrupulous dealers will find all means to cheat people, even to the extent of opening up a shop!
Jade : Stone from Heaven
Jade has been the centre of Chinese civilisation for more than 5000 years. Earliest use of jade were found in the tombs of Neolithic cultures e.g HongShan (3500BC to 2500BC) and LiangZhu (3000BC to 2000BC). Jade has been prized by the Chinese for thousands of years as the most precious of all minerals. Believed to possess magical powers, jade was indispensable during the early societies, be it in rituals or ceremonies. It’s enduring and ageless surface texture came to be associated with immortality, while its abstract qualities represented a pinnacle of simplicity and elegance of design. No other culture has valued jade or any other mineral for such a long period of time, nor indeed accorded any mineral such literary and philosophical attention.
Jade was a privilege only to the rich and powerful people, and it embodied its owners during their lives and afterlives. Archeological findings of the Chinese Bronze age from Shang Dynasty (BC1600 to 1050BC) and Zhou Dynasty (BC1050 to 221BC) indicated that burial jades were crucial to the afterlife of the elites. This belief reached its peak during the Han Dynasty (206BC-9AD), where jade was believed to preserve the body of the dead; the jade suit of Prince Liu Sheng, consort Dou Wan and King of Nanyue were spectacular evidence on the mystique of jade in ancient China.