F A C E T - N A T I O N
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All green jade obtains its color from the presence of chromium. This
color is often called 'imperial jade', meant to describe a cabochon of
the most intense, saturated, uniform, emerald green. It is quite rare
and can be among the most expensive of all gemstones. In addition to
fine color, a truly 'imperial' jade must exhibit translucence. In its
darker color range, it is referred to as 'old mine' material; in the
lighter color range, it is sometimes called 'spring green' or 'canary
jade'.
Intense Apple Green. Cabochons should never exhibit too much variation
in color, nor excessive internal inclusions. Certainly, fractures
should never break through the surface of a smooth cabochon. This
shade of apple green is among the most desirable of all jade colors.
Light, translucent apple green. When a bit grayer, it is called 'bean
green'; when a bit more blue, it is called 'celadon green'. There are
over 100 adjectives to describe the qualities of green, (spring
valley, mountain leaf, moss-in-snow, etc.).
Lavender jade, in the blue-lavender color range. All lavender jade
obtains its color from the presence of manganese. Although sometimes
called "blue-lavender", this color is never as intense as lapis blue,
but is really more of a blue-gray. Plum-purple also is classified as a
blue-lavender.
Lavender jade in the pink color range, also the result of manganese,
(or iron-ion transfer). This is the most desirable of the color ranges
of lavender. Lavender is, pound for pound the rarest color to appear
in jade. Be careful of a pink that is extremely intense; this is the
color range that is most suspect as dyed material.
Crystal jade" or "water jade" is a rare, nearly colorless form of
jadeite that is extremely translucent. Crystal jade is the most
translucent of all jades; one can almost read newsprint through it. A
new popularity in this stone is evidenced by recent auction sales in
Hong Kong and its price has risen dramatically.
Red jade comes from the 'skin' of the rock, and is the result of
oxidation that occurs upon extended contact with iron-rich soil or
water. In a sense, the outside of the stone has 'rusted'. The red
color of the skin rarely persists beyond 15 or 20mm, and so large,
fully-red jade objects are rare; red jades often exhibit secondary
colors. Also, bangles and beads in red jade can become costly because
of the material waste inherent in their fabrication.
Like
red jade, yellow jade is also the result of oxidation. Many stones are
mistakenly called yellow jade, such as serpentine or dyed chalcedony.
Truly pure yellow jade is rare; since yellow is considered the color
of the emperor, very fine yellow-tinged nephrite has always been very
desirable, even more costly than pure mutton-fat. In jadeite, pure
yellow jade is still reasonable, although never plentiful.
Gray
is a relative newcomer to the jade palette, only being used as jewelry
for the last several decades. The best gray jade is jadeite, although
gray nephrite is well known. Much of the best gray jade comes from
Siberia. The color range is from a light 'flannel' to a dark 'marble'.
On occasion, gray jade is streaked or spotted with green, and that can
add considerably to the value.FTC Disclosure Guidelines
At long last, the Federal Trade Commission (FTC) announced that it would change its rules on gem enhancement disclosure effective April 10, 2001. As a result of this decision, the new clause requires sellers to disclose if "the treatment has a significant effect on the stone's value." This decision was sparked by a petition from the Jewelers Vigilance Committee (JVC) and was supported by 15 other industry organizations.
With regard to jadeite jade, this ruling clearly requires disclosure of 'B' treated jade by the seller before the sale takes place.
We also note that, in addition to the consideration of "significant effect on a gemstone's value", the FTC also asserts that "it is unfair and deceptive to fail to disclose that a gemstone has been treated if the treatment is not permanent…or the treatment requires special care requirements." In the case of jadeite jade, the 'B' jade treatment has not proven to be permanent. In addition, natural jadeite jade is impervious to acids and is frequently cleaned after polishing with the use of acetone, whereas cleaning 'B' jade in this manner would permanently damage the stone. Thus, there certainly are 'special care requirements' for 'B' jade. Hence, the FTC's new ruling requires the disclosure of 'B' jade by the seller on all three counts of the guidelines.
We again point out that Mason Kay carries only natural, untreated jadeite jade.
Jade Simulants
Jade
is probably the most mis-identified of all important gemstones. There
are many minerals that have a passing resemblance to jadeite and
nephrite, and they are often misrepresented as jade. The high value of
jade has made it a favorite target.
In East Asia, and elsewhere, it is not unusual to find other "hardstones"
sold as one form or another of jade. The terms "new jade", "Hunan
jade", "Sinkiang jade", "Khotan jade" and "Korean jade" all refer to
stones other than jade, as do "Transvaal jade" and "Queensland jade".
Other common jade simulants, (opposed to "synthetics", which are not a
problem in jade), are listed below:
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Other common jade simulants are carnelian for red jade, muscovite or
zoisite for lavender jade, and bowenite (grossularite garnet) for
green jade. In addition, watch for calcite, prehnite, idocrase,
jasper, malachite and maw-sit-sit.
Jade was thought to preserve the body after death and can be found in emperors' tombs from thousands of years ago. One tomb contained an entire suit made out of jade, to assure the physical immortality of its owner.
In Central America, the Olmecs, the Mayans, and the Toltecs also treasured jade and used it for carvings and masks. The Aztecs instituted a tax in jade, which unfortunately led to the recycling of many earlier artworks.
The Portuguese, who brought home jade pieces from their settlement in Canton, China, called jade piedre de ilharga , or stone of the loins, because they believed it to be strong medicine for kidney ailments. Jade objects brought back to Spain from the new world were called by the Spanish version of this phrase piedra de hijada . This became the French ejade and then, finally, jade.
The ancient jade of China was what we today call nephrite jade: an amphibolite mineral. Today it is jadeite jade that is considered the real jade, commanding prices much higher than nephrite because it comes in much more vivid green colors and finer translucency. Jadeite jade is much rarer than nephrite: almost all the jadeite on the market comes from Burma.
Jadeite dealers are some of the world's biggest gamblers: Boulders are sold intact, with only a tiny window cut in the side to expose a small section of the interior. The buyer has no idea what lies inside: valuable green jadeite or perhaps only white inexpensive white or brown jade. And boulders sell for hundreds of thousands of dollars.
The top jadeite jade is usually cut into smooth dome shapes called cabochons. Jadeite bangles are also very popular in Asian countries. Beads are also very beautiful and some important jadeite necklaces made during the art deco period have fetched hundreds of thousands of dollars in auctions.
Because of its smooth even texture, jade has long been a preferred material for carving. The most common shape is the flat donut-shaped disc called a pi, which is commonly worn as a necklace.
Jadeite jade is most treasured for its vivid greens, but it also comes in lavender, pink, yellow, and white. The Emerald Buddha, the sacred image that is enshrined at Wat Phra Kaeo in Bangkok, Thailand, is actually beautiful emerald-green jadeite. Nephrite is found in less intense dark spinach greens, white, browns, and black.
While jadeite is mined today primarily in Myanmar, small quantities can be found in Guatemala. Although neolithic jadeite axes were found in Europe, it is not known where this prehistoric jadeite was mined, although it is possible that the material came from a deposit in the Alps. Nephrite is mined in Canada, Australia, the United States, and Taiwan.
Jade is most often sold by the piece rather than per carat. Although the overall color is the most important value factor, attention is also paid to translucency, texture, and also to pattern. Certain patterns, including moss in snow, are highly valued.
Both jadeite and nephrite are very durable and tough, although jadeite is slightly harder than nephrite due to its microcrystalline structure. Clean with mild dish soap: use a toothbrush to scrub behind the stone where dust can collect.
It is an exceptionally tough material, and was first used for things such as axe heads, knives, and weapons. Later, as other materials could replace jade as a weapons material, it became appreciated for its beauty. Jade has a Mohs hardness of between 6.5 and 7.0 [1].
Nephrite can be found in a creamy white form as well as a green color, while jadeite shows more color variation. Of the two, jadeite is rarer, and is the form of jade mostly used in Central America. Nephrite jade was used mostly in China, Myanmar and New Zealand.
Jade is the official gemstone of British Columbia.
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History
During Neolithic times, the key known sources of nephrite jade in China for utilitarian and ceremonial jade items were the now depleted deposits in the Ningshao area in the Yang Ze River delta (Liangzhu jade culture 3400–2250 BC) and in an area of the Liaoning province in Inner Mongolia (Hongshan culture 4700–2200 BC). Jade was used to create many utilitarian and ceremonial objects, ranging from indoor decorative items to jade burial suits. From about the earliest Chinese dynasties until present, the jade deposits in most use were from the region of Khotan in the Western Chinese province of Xinjiang. There, white and greenish nephrite jade is found in small quarries and as pebbles and boulders in the rivers flowing from the Kuen-Lun mountain range northward into the Takla-Makan desert area. River jade collection was concentrated in the Yarkand, the White Jade (Yurungkash) and Black Jade (Karakash) Rivers. From the Kingdom of Khotan, on the southern leg of the Silk Road, yearly tribute payments consisting of the most precious white jade were made to the Chinese Imperial court and there transformed into objets d'art by skilled artisans as jade was considered more valuable than gold or silver.
Jadeite with its bright emerald-green, pink, lavender and brown colors was imported from Burma to China only after the 17th century and became known as Feitsu or Kingfisher (feathers) Jade.
In New Zealand, where it is known as greenstone or pounamu, nephrite was fashioned for centuries by Maori to make weapons and ornaments, and is still widely used to make carved jewelry although the mining of it is restricted and closely monitored.
Other Names
Besides the terms already mentioned, jadeite and nephrite are sometimes referred to by the following:
Jadeite
Agate verdâtre, Feitsui, Jadeit, Jadeita, Natronjadeit, Yunnan Jade, Yu-stone
Nephrite
Aotea, Axe-stone, B.C. Jade, Beilstein, Grave Jade, Kidney Stone, Lapis Nephriticus, Nephrit, Nephrita, Nephrite (of Werner), New Zealand Greenstone, New Zealand Jade, Spinach Jade, Talcum Nephriticus, Tomb Jade
Faux Jade
Many minerals are sold as jade. Some of these are: serpentine (also bowenite), carnelian, aventurine quartz, glass, grossularite, Vesuvianite, soapstone (and other steatites such as shoushan stone) and recently, Australian chrysoprase. "Korean jade," "Suzhou jade," "Styrian jade," "Canadian jade," "Olive jade" and "New jade" are all really serpentine; "Transvaal jade" is grossularite. Other names for fake jade are: "Honan jade," "Metajade" and "Sinkiang jade."
Real jade may be enhanced (sometimes call "stabilized"). There are three main methods, sometimes referred to as the ABC Treatment System:
- Type A jadeite has not been treated in any way except surface waxing.
- Type B treatment involves exposing a promising but stained piece of jadeite to chemical bleaches and/or acids and impregnating it with a clear polymer resin. This results in a significant improvement of transparency and color of the material. Currently, infrared spectroscopy is the only test for the detection of polymer in jadeite.
- Type C jade has been artificially stained or dyed. The red color of Red jade can be enhanced with heat. The effects are somewhat uncontrollable and may result in a dull brown. In any case, translucency is usually lost.
Type A treatment is the only acceptable enhancement by professional collectors.
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| Jade refers to two chemically
different stones: jadeite, a silicate of sodium and
aluminum, and nephrite, a silicate of calcium and
magnesium. Although different, they share many common
characteristics. In Europe, the technical characteristics
of the two varieties were first published by Damour in
1863; the Chinese were aware of the differences long
before. Jadeite, the rarest and most valuable form of jade, is also known as 'Burmese Jade', (after its traditional and still most important source). It has been in wide use only since the mid-18th century, and today is considered the 'precious' form of jade. Most 'fine jewelry' items of jade consist of jadeite. Jadeite exhibits a wide palette of sometimes vibrant colors, often with translucence. Green is the most valuable color; in particular, a translucent emerald-green is the most prized of all, and is sometimes called 'Imperial Green'. Jadeite is also available in lavender, red, yellow, black and white. 
Nephrite, the traditional form of jade, has been used for over 5000 years by many different cultures throughout the world. It is the Chinese, however, that raised the craft of jade carving to an art, and who appreciated it on the deepest levels; the rich mix of mythology and religion in China seemed to find it's highest expression in the virtues of jade. Nephrite colors are subdued, and range from grey to brown to blue-green to black. Translucence is rare. The highest quality comes from Siberia, and sometimes New Zealand or Australia. Taiwan has good nephrite, but the giant of all producers today is British Columbia. |
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Jade The myth of jade Jade – a gemstone of unique symbolic energy, and unique in the myths that surround it. With its beauty and wide-ranging expressiveness, jade has held a special attraction for mankind for thousands of years. This gem, with its discreet yet rather greasy lustre, which comes in many fine nuances of green, but also in shades of white, grey, black, yellow, and orange and in delicate violet tones, has been known to Man for some 7000 years. In prehistoric times, however, it was esteemed rather more for its toughness, which made it an ideal material for weapons and tools. Yet as early as 3000 B.C. jade was known in China as yu, the 'royal gem'. In the long history of the art and culture of the enormous Chinese empire, jade has always had a very special significance, roughly comparable with that of gold and diamonds in the West. Jade was used not only for the finest objects and cult figures, but also in grave furnishings for high-ranking members of the imperial family. Today, too, this gem is regarded as a symbol of the good, the beautiful and the precious. It embodies the Confucian virtues of wisdom, justice, compassion, modesty and courage, yet it also symbolizes the female-erotic. A visit to the jade market, be it in Hong Kong or Rangoon, or at one of the Hong Kong jade auctions organized by Christie's, can give some idea of the significance this gem has for the people of Asia. However, as long ago as the pre-Columbian period, the Mayas, Aztecs and Olmecs of Central America also honored and esteemed jade more highly than gold. New Zealand's Maoris began carving weapons and cult instruments from native jade in early times, a tradition which has continued to the present day. In ancient Egypt, jade was admired as the stone of love, inner peace, harmony and balance. In other regions and cultures too, jade was regarded as a lucky or protective stone; yet it had nowhere near the significance that it had in Asia, which was presumably due to the fact that people knew relatively little about this fascinating gem. Fortunately however, in recent times, people's understanding of this gem, which fascinates not only the connoisseurs by its perfect interplay of hardness and toughness with an enchanting range of colors and fine lustre, has improved; and their esteem for it has been on the increase all over the world.  What
is jade?'Jade', or yu, as it is called in China, is strictly speaking a generic term for two different gems, nephrite and jadeite. The name is derived from the Spanish piedra de ijada, loin-stone, jade having been recognized by the Amerindians as a remedy for kidney ailments. Because of its beneficial effect on the kidneys, the stone was also known as lapis nephriticus. That, indeed, is where the term 'nephrite' came from. Jadeite and nephrite are both regarded in China as zhen yu, 'genuine jade'. It was not until the beginning of the 19th century that mineralogists and gemologists started to differentiate between them, since they bear a considerable resemblance to each other in terms of their appearance, their hardness and the properties they exhibit when being processed. Both are tough, since they consist of dense, close-grained, matted aggregates, but they differ from one another in their chemical composition and colors. Nephrite ranges mainly from mid to dark green or grey-green, but it can also be white, yellowish or reddish. Rarer, and somewhat tougher, jadeite displays hues which include green, but also white or pink, and reds, blacks, browns and violets. In both minerals, the way the color is distributed varies a great deal. Only in the very finest jade is the color evenly distributed. Both nephrite and jadeite often have veins, blemishes and streaks running through them, though these may not always be regarded as flaws. On the contrary, some of these patterns are considered particularly valuable. Jade: from raw material to finished product Jadeite is rarer than nephrite and is therefore regarded as more precious. Nephrite deposits have been found in China, New Zealand, Russia, Guatemala and the Swiss Alps. Dark green jade, so-called Canada jade, is also found in Western Canada. Jadeite is found in China, Russia and Guatemala, but the best stones come from Burma, now known as Myanmar. There, at the annual 'Gems, Jade and Pearls Emporium', blocks of jade in all sizes are auctioned. When purchasing the raw materials, the dealers need to be fairly lucky, since the nodules, blocks and fragments are sold either whole or after having been cut into slices, and there is only a very small window, the result of some initial grinding. So the buyer cannot see exactly what is hidden on the inside: valuable green jade, or an almost worthless, speckled or streaky material. It is not until the cutting process begins that the real quality is revealed. In the jade-cutting centres of Canton, Beijing and Hong Kong, the raw material is processed with carborundum and diamond powder. Since jade is, as a rule, not transparent, but has a fine lustre, the cabochon is the form best suited to it. Thin slivers, which can be worn as pendants, and jade bracelets are popular too. Round, cylindrical and flat shapes can be combined to make attractive necklaces. Traditionally, jade is processed into slender figures, filigree images or thin-walled vessels. This is sometimes erroneously referred to as jade carving. Unwanted material is in fact removed during the cutting process, and the stone is subsequently polished. Here once again we see the subtle difference between nephrite and jadeite: whilst polished nephrite has a surface with a resinous lustre, the glassy lustre of jadeite after polishing seems to shine almost like that of a mirror.  What distinguishes good jade? For collectors as well as jewelry lovers, jade is a fascinating gemstone. In Asia, above all, it is collected as an antique. Besides the quality of the gem and its processing, religion and faith also play an important role. In the West, many people prefer to collect jade in the form of snuff-boxes, cigarette holders, small bowls or rings. Since each collector has his or her own taste and his or her own likings with regard to color, style and shape, it is no easy matter giving definite advice on the purchase of jade objects. However, jade is, at the same time, a wonderful gem, not only in its traditional guise, but also in more modern designs. Especially in recent years, creative jewelry and gemstone producers have come up with some wonderful, up-to-date jewelry design, thus sprucing up the image of jade, which had had rather a traditional character for quite some time. In general, the value of jade is determined according to its color and the intensity of that color, the vivacity and texture, and its clarity and transparency. Likings for particular colors vary very considerably from region to region and culture to culture. In green jade alone, the connoisseurs differentiate between seven main qualities, from the intense, even green of imperial jade, via apple green and spinach green, all the way to the lighter and to more heavily speckled shades of green. These special nuances often overlap and can hardly be recognized by the untrained eye. In the USA and Europe, emerald green, spinach green and apple green are regarded as particularly valuable. In the Far East, on the other hand, pure white or a fine yellow with a delicate pink undertone is highly esteemed. In the world of jewelry, the fine violet nuances of lavender jade are very popular. It is however the rare, emerald green of imperial jade, which shines through at the edges, a color of incredible depth, which fetches the highest prices. Unfortunately, since not only good and natural jade is offered for sale, but often fake or poor-quality products or stones which have been colored or otherwise treated, it is advisable to buy good jade only from reputable dealers and jewelers, whether the purchase is being made for a collection or as an individual piece of jewelry. Symbolic energy and beauty, the traditional and the modern are combined in jade in a particularly harmonious way. And in gemstone therapy it is said that jade 'stimulates creativity and mental agility on the one hand, while also having a balancing and harmonising effect.' So this beautiful gemstone brings us joy, vivacity and happiness all at the same time – and what, in our times, could we possibly need more?
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