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Differences
among Type A, B, and C Jade
Since
the beginning of 1980's, the demand for jade has increased in mainland
China, Taiwan and South Korea. People desire high quality jades, but there
are fewer and fewer naturally produced jades (Type A jade). The price of
Type A jades become higher and higher. To meet the need of the customers,
the jade manufacturer try their best to use chemical bleach to remove
impurities from the lower end jades. This treatment damages the structure
integrity of the jade. This kind of jade are also called Type B jades.
The
classification of Type A, Type B, Type C jade is an international
classification and is used by the jade industry.
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Type
A Jade (Natural Jade):
Type
A jade, natural, untreated jade, only undergoes a traditional process, including plum juice washing
and polishing with beewax.
These procedures are internationally recognized as standard practice and
are not defined as "artificial treatments". It is not disguised
with any dirt picking, high temperature or high-pressure treatments.
The
color is natural, so they are called "true color".
Type
B Jade:
Type
B jade, bleached, polymer impregnated jade. To
distinguish Type B jade, you need to know the structure of jade as well as
the principle and procedure of the processing of Type B jade. We know that
the chemical composition of jade is NaAlSi2O6, which is composite with
columnar crystals and the interlocking structure made it to be a very
tough mineral stone. Because of oxygenation and hydrolysis, oxides such as
iron, manganese and calcium are adhered on the surface and even immerge
into the interspaces between crystal, which turn the color of the jade
into orange, brown, black, or grew. These impurities influence the
transparency, as well as the color of the jade. The purpose of using
powerful acid such as sulfuric acid and chemical on the jade is to remove these impurities,
improve the transparency and to make the green color of jade uninfluenced
by the varied colors (caused by the chrome and iron ion), which make it
more delicate and charming (the green color is the original color of the
jade which cannot be removed and affected by powerful acid). Sometimes the acid is heated to increase its strength. After the jade has been chemically bleached to remove impurities,
it will then
impregnated with polymer to enhance translucency. Polymer is
injected into the jade with the use of a centrifuge. At this stage
the jade is covered with hard and clear plastic like coating.
The quality
of this kind of jade is not natural, its structure integrity has been
damaged and become loose. The artificially treated Type B jade will
become unstable and discolor after a certain period of time since heat or
household detergent will break down the polymer.
Type
C Jade:
Not
only the Type C jade has been chemically bleached to remove impurities, it
has been dyed to enhance its color. The color will be very rich but will
not retain its brilliant coloration and will discolor after certain period
because the chemical used on treatment is not stable. The transparency and
equality will be loose under strong light, body heat or
household detergent.
When
they say it is a "Real Jade" or "Real Jade with Natural
Color". It may be a Type A jade or it may be not. Treated
jade (Type B jade) is still 100% real jade with 100% natural color, it is
just not Type A jade because it has been artificial treated.
Type
A Jade's "Certificate of Jade Identification":
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