Jade
Jewelry and Art Highly Regarded for Thousands of Years
By Rob Longewell
Jade
is in high demand in many different forms of jewelry and art.
What
is Jade? "Jade" is a cultural term used for a very durable, and often
beautiful, material that has been fashioned into tools, sculptures, jewelry,
gemstones, and other objects for over 5,000 years. It was first used to
manufacture ax heads, weapons, and tools for scraping and hammering because of
its toughness. Jadeite and nephrite are materials that have both been called
"jade" for thousands of years.
Early
Use of Jade in Tools: People have used jade for at least 100,000 years. The
earliest objects made from jade were tools. Jade is a very hard material and is
used as a tool because it is extremely tough and breaks to form sharp edges.
Most
jade does not have a color and translucence that is expected in a gemstone.
However, when early people found these special pieces of jade, they were often
inspired into crafting them into a special object.
Some
of the oldest jade jewelry found has been Green jadeite buttons. Hand-made,
antique Chinese jadeite buttons have the typical color of quality green
jadeite. The jadeite in these buttons was most likely mined in Burma Then,
because some specimens had a beautiful color and could be polished to a
brilliant luster, people started to use jade for gemstones, talismans, and
ornamental objects. Although most people who think of jade imagine a beautiful
green gemstone, the material occurs in a wide variety of colors that include
green, white, lavender, yellow, blue, black, red, orange, and gray.
Jade
dragons have been popular ever since the Western Han Dynasty (202 BC - 9 AD).
Mayan
ax head made from jade have also been found. Historically, Jade has been used in jewelry,
ornaments, tools, weapons, and as gemstones.
Originally,
all jade objects were thought to be made from the same material. However, in
1863 a Frenchman, Alexis Damour, discovered that the material known as
"jade" could be divided into two different minerals: jadeite and
nephrite.
Because
these two materials can be difficult to distinguish, and because the word
"jade" is so entrenched in common language, the name "jade"
is still widely used across many societies, industries, and academic disciplines.
In
this article, the word "jade" will be used for undifferentiated
materials. "Jadeite" or "nephrite" will be used when the
identity of the material is known. The word "nephrite" is also an
imprecise term. It is used for materials composed of the minerals actinolite
and tremolite. Jadeite and nephrite have
distinctly different mineral compositions. Jadeite is an aluminum-rich
pyroxene, while nephrite is a magnesium-rich amphibole. However, the two
minerals have very similar physical properties in the eye of the average
person. Only trained observers with significant experience are able to reliably
differentiate them without mineral testing equipment. This is why jadeite and
nephrite were not properly distinguished by scientists until 1863.
China
has been the leading producer of jade objects for over 5,000 years. A few
hundred years ago, master Chinese craftsmen who worked with jade daily
recognized that some of the jade obtained from Burma (now the Union of Myanmar)
was different. It was harder, denser, worked easier, and produced a higher
luster upon polishing. It gradually became the form of jade preferred by
Chinese artisans and the jade most highly prized by the Chinese people. They
realized this long before scientists differentiated jadeite and nephrite in
1863.
Unknowingly,
Chinese craftsmen had distinguished jadeite from nephrite and appreciated it
enough to pay premium prices for jadeite. However, they didn't have the
knowledge and equipment of chemistry and crystallography to distinguish them in
a formal way.
Rarely,
the Chinese craftsmen encountered fine-grained jadeite with a bright
translucence and a rich, uniform green color. This beautiful material was given
the name "Imperial Jade" and regarded as the stone of highest
quality. At that time in China, ownership of Imperial Jade was reserved only
for the Emperor. Now, anyone who can afford it can own Imperial Jade. The best
specimens can cost more per carat than high-quality diamonds.
A
pendant made from a green nephrite known in New Zealand as "Maori Green
Stone" or "Maori Jade." Photo © iStockphoto and Steve Patterson.
Jade
Treatments: Waxes, dyes, bleaches, polymer impregnation, heat treatments, and
other procedures are sometimes used to improve the color and luster of jadeite
and nephrite to give them the appearance of the finest jade. These treatments
can usually be detected in a careful examination by an experienced person using
a microscope, hand lens, and ultraviolet light. An untrained person is unable
to recognize most of these treatments. Sellers have an ethical obligation to
accurately identify the material that they are selling and reveal any treatment
that has been applied.
Commonly
Confused With Jade: Pictured here are four gems commonly confused with jade.
From top left and going clockwise they are chrysoprase, maw sit sit, serpentine,
and hydrogrossular garnet. They have a color, luster, and translucence that is
known to occur in jade. See more details below.
Other
Materials Confused With Jade: A number of other minerals and materials that are
commonly cut and polished are easily confused with jade. All of these materials
can have a color, luster, and translucence that is very similar to jade - so
similar that the average person is unable to recognize them. These materials
are often used to manufacture cabochons, beads, and other objects in the same
style as jade. They sometimes enter the
jade market without distinction.
The caution to buyers is
this: If
you are spending serious money for a jade object, be sure that you are buying
from a knowledgeable and trusted dealer. If you don't know what you are buying,
then you should pay no more for jade than you would pay for the same object
made from a material with no intrinsic value.
New
Zealand Greenstone: These boulders, harvested from glacial outwash on the South
Island of New Zealand, were originally called "Pounamu" by the local
Maori people, then "greenstone" (a literal translation) by European
explorers. They are actually nephrite jade. They were used by the Maori for
making tools and weapons. Pieces with an attractive color or pattern were used
to make ornaments and fashioned into pendants. Public domain image by Sarang.
"Toughness"
is the ability of a material to resist fracturing when subjected to stress.
"Hardness" is the ability of a material to resist abrasion. Early
toolmakers took advantage of these properties of jade and formed it into
cutting tools and weapons. It was used to make axes, projectile points, knives,
scrapers, and other sharp objects for cutting.
Use
of Jade as a Gemstone: Jade is a durable, colorful material that can be worked
into shapes and given a high polish. These properties make it a very desirable
gemstone. Jade has been used to make a variety of jewelry items such as
pendants, necklaces, rings, bracelets, earrings, beads, cabochons, tumbled
stones, and other items.
These
jewelry items are often made of solid jade, combined with other gems, or placed
in settings made from gold, silver, or other precious metals. In addition to
jewelry, jade is used to make small sculptures, ornaments, religious art, and
small functional objects.
More
details on other minerals that look like Jade and are often sold as inexpensive
Jade:
Maw
Sit Sit is a rock composed of jadeite, albite, and kosmochlor (a mineral
related to jadeite). It has a bright chrome-green color and accepts a bright
polish. For those reasons it is used as a gemstone. Maw sit sit was first
properly identified in 1963 near the village of Maw Sit Sit in northwestern
Burma in the foothills of the Himalayas. This is the only location where it has
been discovered to date. It is used to cut cabochons and produce small
sculptures. Because of its scarcity and low production, it is rarely seen in
jewelry
Chalcedony
is a translucent variety of microcrystalline quartz that occurs in a range of
colors similar to jade. Chrysoprase is a bright green chalcedony colored by
chromium that, when cut into cabochons, beads, and small sculptures, will look
very similar to jade. Chalcedony occurs in a variety of other translucent
colors such as black, lavender, yellow, and orange that can look like the color
varieties of jade. Chalcedony can be a very close gemstone look-alike with
jade. It can be differentiated from jade using is lower specific gravity and by
a variety of instrumental methods.
Serpentine
occurs in a variety of wonderful translucent to nearly transparent green and
yellowish green colors that look very much like jade. It is a metamorphic
mineral that is often found in the same geographic areas and same types of
rocks as jade. Serpentine is significantly softer than jade and also has a much
lower specific gravity.
Vesuvianite,
also known as idocrase, is another jade look-alike that is very difficult to
distinguish from jade without laboratory testing. It has similar hardness,
specific gravity, and physical appearance. It is not nearly as tough as jade
and will break easier - but that requires destruction of the specimen.
Hydrogrossular
Garnet is a green massive variety of garnet that is usually green in color with
black markings. It looks so much like jade that in South Africa, where it is
common, it is known as "Transvaal Jade." It is frequently cut into
beads, cabochons, and small sculptures.
Aventurine
is a trade name used for a green quartz that is often colored by fuchsite
inclusions. These typically color the quartz a light to dark green color and
produce some aventurescent sparkle. Aventurine is sometimes confused with jade.
All of the above natural
minerals and rocks can be confused with jade. Many people like them, enjoy them, and knowingly
purchase them for that reason. It is important to know that these jade
look-alikes, along with plastic and glass made into objects in the same style
as jade, are abundant in the market place. Know
what you are buying or purchase from a dealer you can trust if you are shopping
for these items and desire jade instead of an alternative. Errors and deception
are common.
Geography
of Jade: Most people immediately think of China as the source of jade and jade
objects. China has always been an important producer of jade, a leading jade
cutting center, jade consumer, and jade market. The only time dominance in any
of these activities moved outside of China was between World War II and the
early 1980s. At that time the Chinese government suppressed jade commerce, and
Hong Kong temporarily became the center of jade commerce.
Jade
jewelry and jade artwork are extremely important in China. Jade is more
important in China than the importance of diamonds in the United States.
Per-carat prices for the best imperial jade in China rival the per-carat price
paid for diamonds in the United States.
Since
prehistoric times, jade has been used to make tools, weapons, and important
ornamental objects in Asia, Europe, Australia, the Americas, and numerous
Pacific islands. The toughness of jade made it an excellent material for making
tools and weapons.
Because
of its beauty, people held jade in highest esteem and used it to make religious
art and ornaments for their rulers. None of these ancient cultures had contact
with one another, yet they all independently used jade for many of their most
sacred and important objects. Such is the appeal of jade.
Jadeite
is typically found in rocks that have a higher pressure origin than nephrite.
This normally causes a geographic separation of jadeite and nephrite deposits.
From
ancient times, much of the prospecting for jade has been done in the steeper
parts of drainage basins, where pebble- to boulder-size pieces of rocks are
found in stream valleys. Boulders and pebbles of jade normally have a brown
weathering rind that hides their inner beauty and potential value.
Prospectors
search these valleys looking for jade boulders. Small windows are often cut
into the boulders in the field to assess the material's quality and to
determine if it is worth the labor of transport.
Jade
boulders can be very difficult to transport without damage. Human and animal
labor was the only way to transport them historically. Today in some areas that
is still the only way to move the boulders to market. Where economics allow, a
helicopter with a basket or sling on a cable will fly in to difficult areas.
Workers on the ground will load jade boulders, and the helicopter will lift
them out. Although helicopters are very expensive to use for this type of work,
one nice boulder can be worth many thousands of dollars or more in rough form.
Some
jade is also mined from hard rock deposits. Boulders are sometimes mined from
ancient conglomerates, but ophiolite exposures are the most important type of
hard rock deposit. Ophiolites are the metamorphosed rocks of ancient subduction
zones, now exposed at the surface by faulting or uplift, followed by exhumation
by weathering. Jade is mined from ophiolites by both surface and underground
methods.
Geographically,
much of the world's jade is found around the rim of the Pacific Ocean, where
subduction transports large slabs of oceanic lithosphere beneath continents and
volcanic island arcs. This accounts for much of the jade found in South
America, Central America, the United States, Canada, eastern Asia, and New
Zealand.
Perhaps
the most attractive and valuable jade found in the United States is from the
area around Jeffrey City and Crooks Gap in Wyoming. There, nephrite jade is
found by prospecting alluvial sediments, looking for jade in stream-rounded
pebble- to boulder-size pieces.
Wyoming
jade: Wyoming Jade: A nice oval cabochon cut from Wyoming jade. This cabochon
was cut from a thin slab of jade only a few millimeters thick to conserve
material and produce a translucent stone.
Social
Importance of Jade: In the United States and Europe, diamonds, rubies,
sapphires, emeralds, opals, garnets, and a few other gems are much more popular
than jade. Jade is not thought to be as precious in these regions as it is in
China.
The
Chinese have a much higher regard for jade than any other people. For thousands
of years, jade has been the most popular gemstone in China. Chinese emperors
desired excellent specimens of jade, and they traded or waged war with distant
people to acquire them.
In
China, gifts made from jade are given at almost every important station in
life, such as birthdays, anniversaries, marriages, and other celebrations. It
is also a commonly used material for producing religious art. China is the
country where the importance of jade is the highest.
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