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All About Jade
What is it?
Among the oldest of known gemstones, jade has been appreciated at
many different levels throughout history: first as an object used in
daily life, then in pagan times as an object of ritual. Later, it
acquired economic status as an item of barter and wealth, and today
it has become a medium of art and personal adornment.
Jade refers, actually, to two chemically different stones: jadeite,
a pyroxene or a silica-bearing mineral, and nephrite, an amphibole,
or a ferro-magnesium silicate. Although different, they share many
common characteristics. The Chinese were aware of the difference by
the mid-1700's while, in Europe, the technical differences were
first published in 1863. We regard both forms simply as "jade."
Nephrite jade, which the Chinese grew to appreciate so deeply, was
the form of jade that they first encountered in the Neolithic
period. When jadeite jade was first introduced into China, it was
called Fet'Sui or kingfisher jade because of the brilliance of
colors it manifested and to distinguish it from the traditional
nephrite form of jade. In time, jadeite eclipsed nephrite in terms
of value, and today it is considered gem jade. Today's fine jewelry
market uses jadeite jade almost exclusively; nephrite is generally
valued for its antiquity, carving excellence and other historical
considerations rather than its intrinsic material value.
Interestingly enough, both the terms jadeite and nephrite refer to
the kidneys because of early beliefs that jade was effective for
diseases of the loins.
Apart from its technical aspects, however, there is a magic about
the stone that inspired cultures as diverse as the Chinese, the
Mayans even the court of Czarist Russia. Its charms elude precise
definition; jade reveals itself in the language of myth and legend.
What are the colors
of jade?
The Chinese identified "ritual colors" of jade and even spoke of
colors "invisible to the eye." In fact, jadeite appears in six basic
colors, with many variations. These are green, lavender, red,
yellow, white and black. Green, the most important and traditional
color, varies though apple green to gray-green and finally
black-green.
There is a special magical item called Imperial jade. Although
originally said to refer to those jades possessed by the emperor and
royal family, Imperial jade today should indicate a stone whose
color is a deep, translucent green, and is without visible flaws or
color variations. Such stones are truly rare.
Lavender jade can be quite dark - almost deep plums purple, and in
some cases can take on a blue cast. At its other extreme, lavender
jade approaches the pink range - though never achieving it - and
lightens to a pale lavender-white. Often, lavender jade exhibits a
sugary texture.
There are written reports of a blood-orange jade, but most red jade
actually ranges from a yellow or beige to a deep russet brown.
Black jade is usually nephrite and, in its finer qualities, is
glassy black. Surface flecks are common and difficult to avoid on
pieces larger than dime size.
White jade, or "pure" jade, can be found in a chalky, opaque white
to a translucent gray-white. A good polish is essential.
The color range for nephrite is not nearly so broad as for jadeite
and is usually characterized by a certain dullness of color and
waxiness of texture. Old stones (from Turkestan) are sometimes
creamy (mutton-fat) white while most modern nephrite ranges from
gray-black to an olive green. There is a coal black nephrite, which
takes a good polish, and is currently mined in Wyoming and
Australia.
It is often asked if there is a blue jade or a pink jade. There is
no known blue jadeite, although a deep blue nephrite is claimed. As
to pink, most jade reported as ink is, in fact, not jade.
Jade very often exhibits several colors within one piece. Although
one pure uniform color is usually best, combinations such as green
and lavender, red and green, or white with strong green are very
desirable. The Chinese have an extensive list of phrases to identify
these combinations and colors: moss-in-snow, chicken-blood,
valley-leaf, old mine, spring grass and many others.
What is the best
color?
Other considerations aside, the hierarchy of color value would be
green, lavender, red, yellow, white and black. This is by no means
an absolute scale; however, no one would argue with the first two.
The finest color of green jade would be close in color to a fine
Colombian emerald, but of a darker hue. In fact, the coloring agent,
chromium, is the same for jadeite and emerald. As the green becomes
lighter or darker than this standard, the value becomes
proportionately less. The same can be said of the other colors (even
black). The ideal is a strong, vibrant color while successively
darker or lighter shades are considered less desirable.
In all cases, except white jade, the degree of translucence enhances
the value, while a lack of translucence diminishes the value.
Translucence alone, in the absence of body color, is called "water"
or "crystal" jade.
What causes these
colors?
In a nutshell, the color and translucence of jade are the result of
the chemical impurities present in the rough and the rate at which
the jade cooled eons ago during the formation process. For example,
green is the result of chromic oxide impurities; lavender comes
about from the presence of manganese; red jade occurs as the end
product of oxidation from surrounding water or earth; black jade
denotes high iron content; white jade is "pure" jade. Of course,
jade contains many other impurities that modify and shade these
colors (quartz, mica, serpentine, etc.).
Will the color of
jade change with time?
In the Orient, jade is considered a living thing that is young, then
matures and grows green with age. It was said that some people had
the ability to make jade turn green more quickly, and that this was
a virtue of their mind and body and soul. Alas, interesting myths
notwithstanding, this simply will not happen!
Many people even today believe that in times of good health, one's'
jade grows richer in color, while trauma or illness will drain the
color (and absorb the travail). The wearing of jade close to the
body was said to ensure health. Interesting though these thoughts
may be, there is no evidence that jade will change color. Quite the
contrary, jade is impervious to oils, perfumes and most cold acids.
Its color is constant, for better or worse.
Where is it from?
Contrary to popular belief, jade has never come from China. The
earliest known jade used by the Chinese (nephrite) probably came
from Turkestan, northwest of China. It wasn't until approximately
1750 that jadeite made its way to China from the hills of northern
Burma. At first, this brilliant green "new" jade was regarded with
some suspicion, but soon it came to be considered as "gem jade."
Nephrite, although usually thought of as an oriental stone, was also
mined and carved in ceremonial fashion by many cultures throughout
history - notably the Maoris of New Zealand, and the well-documented
jade culture of Central America.
Modern nephrite is mined in many places throughout the world.
Taiwan, California, Alaska, British Columbia, Wyoming, New Zealand
and Russia are the major sites. It is not a rare stone. Jadeite,
though it is known to occur (in poor quality) in many places
throughout the world, rarely occurs in fine quality outside of
Burma. Burmese jade (often a synonym for jadeite) exhibits the
finest, brightest colors with the least extraneous impurities. In
its finer qualities, it is
How is it mined?
Jade is mined in gross boulder form from mountain sites as well as
found in the form of float. Being harder than the material in which
it is embedded, it emerges when erosion removes the surrounding,
softer stone. Thus it is often found near water sources. Typical
pieces can vary from one to two pounds to some that weigh seven to
eight tons.
It is said that the earliest jade miners were women who, symbolizing
the female or "yin" principle, would be "drawn to" the jade, which
was said to be symbolic of the male or "yang" principle. Thus, they
would find it more easily in rivers and mountains.
Mining in Burma today proceeds much as it did in olden times - it is
unscientific at best. The monsoon season stops the whole process for
six to nine months of the year and, when the rains clear, the
locations of the sites are often forgotten. There is one clear
improvement: large boulders are no longer broken up at the mining
site in order to bring the smaller, more manageable pieces to
market. We can only hazard a guess as to how much fine material this
primitive process has destroyed over the years. Jade lapidaries now
carefully saw all boulders.
Is it fragile?
Next to "black diamond." Jade is the toughest of all known stones.
This extreme durability (a result of its fibrous crypto- or
microcrystalline structure) explains its early use by many cultures
as tools for farming and hunting. No other stone appears in such a
wide variety of forms: bangles, hololith rings, statuary cups,
spoons and scepters. It is jade's unparalleled toughness that
accounts for its wide variety of uses, and it is this very toughness
that allows for the unmatched delicacy of carving one finds in jade.
What other stone can be carved as a continuous chain, from a single
piece of material, and endure as jewelry or statuary for centuries?
Because of its toughness and hardness, jade even appeals to the
aural senses, for its is said when "jade is struck, it rings true."
Not only has jade been carved as bells, but its pictogram is thought
to have been derived from an early jade bell in the form of three
resonant pieces of jade supported by a string and a clapper.
It is this same durability that allows a family to pass on a
cherished piece from generation to generation and elevates jade from
the realm of an ordinary gemstone to a priceless heirloom.
How expensive is
it?
Whereas most gemstones today are sold and evaluated in terms of
their carat weight, jade is sold by the piece. In its finer
qualities, it can be among the most expensive stones in the world
today. This is in keeping with how the ancients valued jade. It is
said that one emperor traded a piece of jade for fifteen cities.
Because of the rarity of fine material today, those items that
inherently create waste are cut very infrequently. For example, fine
beads, drops or bangles can command astounding prices and are never
plentiful in the marketplace.
Modern nephrite, by contrast, is of far less value. Whereas a fine
jadeite cabochon can range from several thousand dollars on up, the
finest nephrite cabochon rarely exceeds a few hundred dollars. There
is no rarity of nephrite, and this is reflected in the price.
Antique nephrite carvings have value based on the antiquity of the
piece, exclusive of material value alone.
It is because of this vast price differential between jadeite and
nephrite that we recommend all appraisals clearly identify the
material not merely as jade, but more definitively as nephrite jade
or jadeite jade.
How is it carved?
In ancient times, a jade boulder was first cut into slabs by means
of string embedded with a mixture of pig fat and quartz dust kept
constantly wet with water. This process alone could take six months
and more for an average size boulder.
Afterwards, a design would be inked in according to the dictates of
the material. The uppermost consideration was always the best use of
the material. Carving for carving sake was simply not done. Ideally,
the carving would be elicited from within the rock rather than
created by the carver.
As color changes were encountered, patterns would change to
accommodate this within the design. The piece would then be pierced
with hollow reed drills, and then the carving accomplished with
string and abrasive. The key is the abrasive. One does not carve
jade as much as one erodes it, and each carver had his preferred
mixture for cutting and polishing.
All polishing was done by hand in many operations with successively
finer grades of abrasives. Hand and foot powered arbors were also in
common use that time. Again, the exact form of abrasive used was a
trade secret fro shop to shop. Polishing was (and is) as important a
step as the carving itself. All in all, a master carver could well
spend years on a single piece depending on its size and level of
intricacy.
It is said that before the advent of power cutting tools, there were
no poorly carved jades. The process was simply too laborious and
time consuming to allow for errors.
Today, the process is very similar in many respects to the ancient
one. Power hand-tools have replaced the reed-and-string drill,
carborundum saw-wheels do the work of hand drawn bow-saws, and
crushed garnet long ago gave way to corundum and then to carborundum
in the nineteenth century.
Modern methods have speeded up the processing of a piece from
mine-head to window display. The quality available, in the medium to
better pieces, is surprisingly excellent. Some pieces rival the work
the late Ch'ing Dynasty at the height of the golden period. Hong
Kong, the modern center for jade carving in the world, is teeming
with third and fourth generation carvers producing excellent work.
Mainland China, once the most prominent carving center is again
buying rough material at he the Burmese auctions, after a long
hiatus. It would be fitting for China to regain its prominent
position in this art.
Why is it
carved?
When a piece of jade is carved, it is done with a twofold purpose:
to create a pleasing, meaningful object and to remove imperfections
in the material. Given two pieces of jade of equivalent size, color
and translucence, one carved and the other smooth, the smoother
piece is of a higher value. Of course, the value of a carved piece
is dependent not only on the material itself, but on the manner in
which the material is used. In a sense, it is a carver's function to
remove the minimum possible amount of material, while creating a
saleable, aesthetic piece.
What about
dye and fakes?
As with other precious stones, there have been many attempts to
enhance (and even synthesize) jade. Most of these have been
detectable by standard and accessible gemological methods until the
late 1980's when a new process of treating jadeite came about. This
method involves bleaching an already-promising but stained stone,
and then impregnating it with a form of plastic. The result is
called "B" jade. Currently, infrared spectroscopy is the only test
for the detection of polymer in jadite. Mason-Kay uses an infrared
spectrometer to check the authenticity of our product and is one of
the few firms in North America to do so.
Red Jade can be heated to increase the redness, but the usual result
is a dull brown, and translucence is lost. This process, by the way,
is irreversible. Lavender can pose somewhat of a problem; it has a
long history of being dyed in a form of "blueberry juice." In some
cases, dyed lavender can be spotted right off (in fractured
material, dye will accumulate in fissures); but it is not always
possible to detect dyed lavender by eye alone. Most dyes fade with
time and exposure to sunlight. We recommend buying from a reputable
source from which one has recourse.
Common jade fakes include serpentine (also bowenite), carnelian,
aventurine quartz, glass, grossularite, idocrase and soapstone. This
is not a complete list. Bear in mind that materials known as new
jade, Honan jade, Korean jade, metajade and Sinkiang jade are almost
never actually jade. The term jade is synonymous with "precious" in
Chinese and thus "Korean jade" may be no more jade than a "golden
sunset" contains no gold. Again, know your dealer.
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