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Introduction

Location of Jade Rough Material

There are distinctly two materials known as jade in the Western world—nephrite and jadeite. The former is found in the mountains and river beds of Eastern Turke-stan (near Khotan and Yarkand). It is this nephrite material which was familiar to the ancient Chinese as well as later generations.

Nephrite is also found near Lake Baikal in Siberia. It is uncertain when the Chinese first imported this material, but Hansford suggests that trade began after 1850 [19, pp. 46-48]. As many pieces made of this material are typically 18th century, the question remains open.

Jadeite was originally discovered in the tributaries and valleys of the Uru River near Mogaung, Burma. From the late 19th century on, however, the major source has been the Tawmaw Plateau. While there may have been some jadeite brought to China at an earlier time, there is no conclusive record of this until the latter part of the 18th century, during the reign of Emperor Ch'ien-lung [21, p. 44].

In recent years, small deposits of nephrite' and jadeite (the latter reputedly of a similar color quality to Burmese material) have been found on Honshu island, Japan (in Kotaki and Omi); these deposits may have been the original source of material for the numerous jadeite beads excavated from early Japanese Jomon (prehistoric) tombs. There is no evidence, however, that this stone was ever exported to the Chinese mainland. We conclude, then, that the jadeite known to the Chinese was of Burmese origin [36; 52].

The preceding simply clarifies a few points which are sometimes misunderstood, and leads us to perhaps the most astonishing fact of all. Despite varying accounts to the contrary, no definite proof has been established that either nephrite or jadeite was ever quarried in China proper! Some authorities have translated references to jade from Chinese classical writings, but it has been pointed out that the word yü or its calligraphic equivalent also refers to other minerals and sometimes signifies qualities such as beauty, purity, splendor, and the highest honors, rather than a particular stone. Yü does not pertain to jadeite. The Chinese call this Burmese stone fei t'sui after the kingfisher bird which sports a brilliant green plumage. Thus it can be readily seen that the old texts are often misleading.

Jade has been found in other parts of the world. In the United States it is native to Wyoming and California. Large deposits are also found in western Canada and Taiwan. The Maori people of New-Zealand, the Eskimos of Alaska, the Aztecs and Mayans of Central America all carved jade which they found in situ. The Chinese, however, who had to open trade routes and keep the importation of jade rough flowing over thousands of miles via water and beast of burden not only recognized the intrinsic beauty of the stone but possessed the artistic genius to develop this medium from its early archaic form to the simple refinement of the Ming dynasty, on through the highly decorative Ch'ing dynasty. Of course, it is characteristic of human nature to seek that which is difficult to acquire, to conquer that which offers the most resistance, to assume the task which poses the greatest challenge. The Chinese obviously set out to prove themselves capable of not only mastering the actual cutting procedures, but of creating magnificent works of art which bear witness to their artistic ingenuity.

Jadeitc and Nephrite: Their Mineral Properties

Before we enter upon the study of the jade carvings themselves, it is well to know a few basic facts about material, workmanship, and dating. Nephrite belongs to the amphibole group of minerals, and jadeite is a member of the pyroxene family. A detailed study of the chemical composition of each can be found in Hansford's book, Chinese Jade Carving [21]. For our purposes it is sufficient to quote Hardinge, "The wide colour range of the jade-stones is due to the presence, usually in minute quantities, of various metallic oxides, especially those of iron, chromium and manganese" [23]. The color variations are innumerable. Nephrite ranges in color from pale green to moss to spinach, white, gray-white, mutton fat (yellow-white), deep gray, brown, red (rust brown), to black, yellow and combinations thereof. Siberian nephrite is a medium green color flecked with tiny black spots and is often translucent.

Jadeite is generally of purer or more vivid coloring than nephrite due to the presence of chromium, the same element that gives emeralds their rich green color. Jade-ite is snow white, emerald green, lavender, blue, and mixtures of these colors. As mentioned previously, a piece of green-and-white jadeite is often called Jei t'sui. The brilliance of fine jadeite material can be breathtaking! Some years ago, I visited the California home of the late Admiral Yannopoulos, an avid jade collector. Enclosed in a cabinet stood an emerald green, translucent jade incense burner, approximately 9 inches tall by 7½ inches wide, of almost uniform color consistency. The vessel was free of decoration other than the carved loosering handles and dragon finial topping the cover, and it bore a high polish, the extreme simplicity of design permitting full appreciation of the material itself. Such pieces are rare, as pure green jadeite is usually found in small specimens suitable for jewelry, seals, palm pieces, etc.

While humerous texts and catalogues refer to "pink" jade, the description is an erroneous one. In every case where the author has come across examples of this color, both in and out of museum collections, tests have proven the material to be other than jade. Sometimes a jade carving is painted on the inside so that a rosy glow is reflected through the translucent material. More often, however, the "pink" jade carving will turn out to be chalcedony quartz, rose quartz, pink garnet, or thulite. Mr. Robert Crowningshield, Director of the Gemological Institute of America, states that in twenty-five years of examining minerals he has never found a carving, geode, or even the tiniest specimen of "pink" jade. We must conclude then that pink jade is non-existent; all statements to the contrary are either honest mistakes or extravagant fancy.

In addition to the color differences between nephrite and jadeite we should consider the matter of surface quality, which further distinguishes the two materials from one another. Nephrite, when polished, takes on a waxy or soapy appearance. Jadeite gleams with a fine gloss. Hansford describes the "lustre of nephrite [as being] oily rather than vitreous and that of jadeite the reverse" [21]. True, the new nephrite carvings made in Peking today sport a high polish in comparison to the older examples. This is probably due, however, to an improvement in the polishing substances used. Nevertheless, jadeite subjected to the same carving and buffing methods assumes a brighter sheen.

These are the easily visible differences between neph-rite and jadeite. What about some of the invisible elements which differentiate the two? Hardness is an important factor. Friedrich Mohs' scale is used to determine the hardness of minerals. Nephrite measures 6.50, while jade-ite ranks 6.50 to 7 on this scale of 10. The diamond is the hardest stone ranking at 10. So there is a small difference in the hardness of nephrite and jadeite.

Next let us examine the actual consistency of these materials. Though a bit softer than jadeite, nephrite is fibrous, rendering it a little tougher than its counterpart and consequently more resistant to the cutting tools. Jadeite has a crystalline composition, that is, its structure is made up of crystals. Mr. Crowningshield tells of having seen a shattered jadeite specimen, from the center of which a single prism had fallen out intact. Thus we can understand why both nephrite and jadeite offer individual problems which challenge the skill and capacity of the craftsman.

How to Verify Genuine Jade

The expert can usually determine whether a carving is nephrite or jadeite or neither. He is aware of color, polish, and mineral composition. But even the experienced are fooled occasionally. There are many stones which imitate jade. Why care if the carving is jade or not as long as it looks as good? Why is a carving more valuable because it is jade rather than serpentine (sometimes called onion jade or new jade), soapstone, green quartz, green garnet, chrysophrase, smithsonite, or chalcedony? The answer is a multiple one. First of all, fine jade rough is available in very limited quantities. Secondly, other minerals which bear a strong resemblance to jade generally do not exhibit the beautiful color properties of nephrite and jadeite. Last but not least, jade is more durable than its imitators. As usual, there is no satisfactory substitute for the real thing.

Minerologists have devised various tests to establish whether or not a particular example is genuine jade. The simplest method is to attempt to scratch the surface of the stone with a sharp blade. Theoretically, if it scratches it is not real jade. However, certain quartzes and types of serpentine are virtually as hard as jade and will not yield to the knife blade or razor edge. Hence the scratch test is not conclusive. Recently, further difficulty has arisen with the advent of stainless steel razor blades. These harder instruments will bite into genuine jade material, so this test is indecisive.

Nephrite has a specific gravity of from 2.90 to 3.20 and jadeite measures 3.20 to 3.50. Small carvings such as snuff bottles can be immersed in a heavy liquid such as bromoform, the density of which will permit the false jade to float, the heavier genuine jade to sink. This method is not recommended for pieces which have painted decoration or are treated (tinted) in any way, as the chemical liquid is likely to remove the color.

Sir Charles Hardinge notes that experiments were done by the Freer Gallery in submitting jadeite and nephrite to extreme heat. At a temperature of 1,025° centigrade, jadeite liquified to a colorless glass and dried to a distorted shape, while nephrite changed to a yellowish, opaque substance resembling calcined bone [23]. The latter case brings to mind certain examples of jade carving which are thought to have changed color due to exposure to fire or extreme heat (Plate 10).

Obviously the collector, considering what may turn out to be the most prized addition to his cabinet, is not desirous of subjecting it to scratches, drowning, burning, and other means of mutilation! The researchers may keep their share of adventure and we are most grateful for their findings, but it is suggested that when in doubt you take the article to the nearest gemological laboratory such as the Gemological Institute of America which has branches in New York City and Los Angeles. There they will place the piece under the surveillance of scientific apparatus such as the spectroscope and the refractometer. These machines measure the optical physical properties of the material against established standards. The piece will be returned in its original condition and the verdict given with assurance.

Chloromelanite

There is another stone, officially classified as jade, to which very little reference is made in textbooks, namely, chloromelanite. This is jadeite found in Burma. Due to large amounts of iron in its composition, chloromelanite at its best is a deep, rich green color. It is also found in shades of dark green and black. Somewhat like malachite in appearance, the material lacks translucency and has a heavy, almost synthetic look. It does take on the high polish characteristic of jadeite, but generally speaking carvings of this material are clumsy and ungraceful. In recent years, a good number of chloromelanite carvings have been sold on the open market. Probably because of their brilliant green color the prices have been formidable. Nevertheless, the thick, plastic-like quality of this material does not really satisfy the keen aesthetic taste.

A material similar in appearance to chloromelanite, called maw-sit-sit by the Burmese and classified officially as chromealbite feldspar, has been available for the past few years. Its color has a bluer cast than jadeite and the veining varies considerably from the genuine jade. Once again, however, it is advisable to submit the example to reliable testing procedures for absolute certainty.

Japanese Jadeite

In addition to the small finds of Japanese jadeite mentioned earlier, an inferior material has been carved in Japan recently, its appearance quite different from the Burmese stone. "Japanese jade" has a pale green to white ground spotted with green and black flecks and is not translucent. In contrast to the Burmese material it does not take a high polish. Thus, while being the genuine article it lacks the lovely appearance of its Burmese relative.

"Imperial" Jade

The term "Imperial" was originally applied to jade carvings which came from one of the imperial palace collections. As such, these examples were of the highest caliber. We often hear pieces described as "Imperial green jade" or "Imperial white jade" and assume that reference is being made to nephrite or jadeite carvings of the finest quality. However, in recent years it has become common practice to label almost any jade carving as "Imperial" for commercial purposes. In fact the term has been bandied about so carelessly that it no longer carries any legitimacy and should be taken with a grain of salt when heard. One must rely upon one's own knowledge or that of a trusted adviser to determine whether a jade carving is of superlative quality, average, or not worthy of consideration. Name tags mean nothing.

Carving Jade

The actual fashioning of a jade sculpture is a remarkable, arduous procedure. To begin with, a portion of the outer covering or rind of the boulder is cut away and polished to reveal the inner color qualities or veins of the material. It is then decided, according to shape, size, and color composition, the subject best suited to the rough. In modern factories, the manager of the shop makes this decision and draws the design on the jade hulk itself. He then hands the cutting job to the first of many workmen who will contribute his particular talent to the whole. Each carver specializes in one or more phases of the carving process. So a finished carving is the creation of a number of craftsmen who have combined their talents to fashion a work of art. This system did not always exist. It probably came into being during the Ming dynasty and fully blossomed in the period of K'ang-hsi and Ch'ien-lung.

The working of jade is done by hand-operated, simple machinery equipped with tools similar to dentists' drills. Power for the various steel cutting implements is derived from electricity in more modern factories, but up to recent times the gears were turned by a foot-treadle process much like our old fashioned sewing machines. There are many different sizes and shapes of tools employed to execute the splitting of a boulder, the hollowing out of a bowl, the intricate incising of motif, the delicate completion of a loose-ring chain, each requiring the appropriate cutting instrument.

But it takes more than steel to cut jade, for the operation is fundamentally a grinding or wearing away of the stone. Crushed "sand" is used in conjunction with the cutting tools. Hansford has written that up to the time of the collapse of the Manchus in 1912 this sand consisted of quartz, almandine, garnets, and black corundum. Today the most popular abrasive is a synthetic material known as carborundum. This wet abrasive is spread upon the jade rough by hand and replenished periodically. Slowly, tediously, using these very primitive means, the natural rock is shaped into the finished vase, incense burner, mountain of the most precise detail. The last step, that of polishing the completed article, is accomplished with a buffing wheel and a paste called pao yao made of carborundum and other sands found in China.

Undoubtedly, in earlier times there were individual artists who conceived the original design and carved the jade in its entirety. Much to our regret, however, jade carvings were rarely signed by the artist. And to make things more difficult, the names of jade craftsmen have neither been recorded nor are they mentioned in old Chinese literature (see page 30). We do note a definite similarity of design in a great many jade carvings, but often come across a piece which is unique in subject, of unusually fine detail, showing an understanding of the material which goes beyond the everyday encounter. Many of the older carvings, particularly those attributed to the Ming dynasty, have this distinguishing quality; each piece being a work of art in itself, displaying the imaginative ability and inspiration inherent to the Chinese lapidary alone.

Richard Gump speaks of the Chinese jade artist as follows: "Many aspects of his craft were traditional, yet no two pieces of jade were the same; each was in itself a new challenge. His greatest talent lay in his acute sensitivity to the stone. He had to know the stone intricately, aware of every flaw and imperfection, intuitively sensing its concealed virtues and potentialities. He was constantly aware of its limitations, yet knew he could do with this material what could never be done with any other His eyes had to be able to see below the surface of the stone, judging how far a streak of color would penetrate, in which direction it would turn " [17].