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Jade
material worked by the ancient Chinese was apparently
nephr1 Central Asia. Jadeite was not known in China
before the 18th , . It was long conjectured that a source
of jade existed in Central +. possibly Mexico or Guatemala.
Jade was finally discovered in wala in 1954, thus confirming
a source for Pre-Columbian mate¬,ite, in the form
of stream boulders, occurs in southern California eral
locations. This material displays various colors, including
~reen, pale green, bluish-green, and white.
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write
occurs in many parts of the world. China is an ancient
Green nephrite comes from eastern Siberia, and the occurrence
Baikal is well known. Material from another Russian
source, -ask, contains black specks of graphite that
make the material ,tinctive. Nephrite from New Zealand
is termed "Maori stone," Zealand greenstone,"
and "Axestone"; it occurs in stream beds red
pebbles easily fashioned into weapons. |
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This material is dark green in
color. Pale-colored nephrite has been found in ,ther European
occurrences include Italy and Germany. Jade Is Alaska and
in British Columbia. Nephrite from Lander, Wyoattained great
popularity in recent years.
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Jade |
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is a distinctive Kenerally mottled green and white
in appearance. Nephritelo Include Washington,
Mexico, Brazil, Rhodesia, and Taiwan.Jade is a
difficult stone to cut and polish and posed great
problems ¬for cutters in primitive societies.
It may have required years just to through large
boulders using a rope "saw" and sand
as an abrasive Generations may have worked on
a single, intricate carving, pieces of stone or
bamboo, water, and sand to fashion intricate ,
detailed curves and figures. It is truly remarkable
that such primitive tools and techniques could
have produced the delicate and hip,, polished
vases, carvings, and brush pots that we see in
museums today .
True jade needs no modifying adjectives in its
name, and stand, its own merits. Many inferior
materials, however, have been nam¬ed using
the word "jade" as a suffix, in hopes
of adding value through inference. All of the
following are tradenames and should be aban -
doned in time, but are included here for reference.
. 
"Korea
jade" is bowenite, a hard variety of the
mineral serpent~ "Transvaal jade" is
actually a massive variety of green Grossular
garnet "Amazon jade" is green microcline
feldspar. "Indian jade" is aven¬turine,
a massive quartz colored by inclusions of green
mica. "American jade" or "Californite"
is a mixture of two green minerals, idocrase -¬and
Grossular. "Australian jade" is Chrysoprase,
a lovely green silica mineral. "Colorado
jade" is also green microcline, and "jasper
jade green jasper. "Fukien jade," "Manchurian
jade," and "Honan jade” are all soapstone.
"Mexican jade" is a green-dyed marble
or calcite "Oregon jade" is a dark-green
jasper. "Silver peak jade" is malachite
green copper mineral.
Other
jade imitations include green glass, white jade
that has been stained or dyed purple or green;
green marble called Verd Antique; various other
green minerals. This list is not complete since
many local tradenames are undoubtedly in use.
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Consumer
Tips-Many materials strongly resemble jade, especially serpentine
and bowenite, and nephrite and jadeite may frequent resemble
each other. Identification of a carving or jewelry item
ma require sophisticated laboratory tests; visual checking
may be satisfactory much of the time, in the hands of a
true expert who has handled tremendous amount of jade, but
even experts can be fooled. The value. of a piece may depend
heavily on the identity of the material from which it is
made.
Dyes
are frequently added to jade to deepen or change the color
White jadeite is frequently stained green or pale purple
to mimic the so-called "mauve jade." The process
can usually be detected in a gem laboratory, but not by
eye.
A
gemstone may be one of a huge variety of colors and still
be jade The misconception that jade has to be green is prevalent,
but ma disappear in time. However, authentication and identification
should be entrusted only to a specialist.
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