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Topaz is a gemstone of all colors, and its most
valuable color is a golden orange-yellow, called
"imperial topaz". Topaz is commonly thought of
as a sky-blue gem, but it was not until this century that
blue topaz became widespread on the gem market. Natural
blue topaz with a deep hue is very uncommon in nature;
colorless to light hued stones are heat-treated to achieve the blue color.
Likewise, topaz rarely occurs naturally in pink;
virtually all pink topaz is heat treated from yellow or
brownish material.
Some topaz from Russian localities are notorious
for fading upon prolonged exposure to light. Stones from
these localities are undesirable as gems. One should
always inquire about the origin of the topaz before
buying it to make sure it will not fade.
Care and caution must be exercised with topaz
gems, for its perfect cleavage may cause it to chip or form internal flaws
if hit too hard. Topaz cutting also requires special
practice for this reason.
USES
Topaz
of all different colors are used in jewelry. The orange,
pink, and blue colors are most often cut for gems, and
colorless topaz is sometimes cut with the brilliant cut,
resembling diamond. Topaz is sometimes found as enormous
flawless crystals, and some gigantic gems and faceted
spheres have been formed from them, making unique and
exquisite gem pieces. Topaz is rarely cut into cabochons.
VARIETIES
On
the gem market, topaz is usually classified by color.
Below is a list of the color names designated for gem
topaz:
Pink
Topaz
Blue
Topaz
Brown
Topaz
Green
Topaz
Other names may be designated to certain types of topaz:
Precious Topaz - used to distinguish topaz from
cheaper fakes, such as citrine
Imperial Topaz - lustrous orange-yellow to
orange-brown variety of topaz
Silver Topaz - colorless topaz
Sherry Topaz - orange-brown topaz
London Blue Topaz - deep blue topaz (the deepest blue
form of topaz)
Swiss Blue Topaz - deep blue topaz (not as deep blue
as London blue topaz)
Paraiba Topaz - sea-green topaz
Brazilian
Aquamarine - False name given to aquamarine
Nerchinsk
Aquamarine
- False name given to aquamarine
Brazilian
Ruby - False name given to pink topaz
Brazilian
Sapphire - False name given to blue topaz
(as well as blue tourmaline)
Hyacinth is an orange-yellow to
yellow-brown variety of topaz. Although the name hyacinth
usually is used to describe a gem variety of zircon of that color, it is also
occasionally used for topaz (in old manuscripts).
Pyncite is occasionally used to describe a
pale yellow topaz.
FALSE
NAMES
Citrine,
a yellow to brown variety of quartz, closely resembles
Topaz of that color. Unfortunately, unscrupulous dealers
have adapted false name for Citrine so the unaware buyer
thinks he is buying the more valuable Topaz. Any
"Topaz" labeled with a prefix name (excluding
those in the variety section of this page and the other
names discussed below) is heat-treated Citrine. Some of the false names
used are:
Gold Topaz
Golden Topaz
Madeira Topaz
False Topaz
Brazilian
Topaz
Bahia Topaz
Citrine Topaz
Several
other false topaz names are:
Brazilian
Topaz - yellow
to yellow-brown sapphire
Indian
Topaz -
yellow to yellow-brown sapphire
King
Topaz -
yellow to yellow-brown sapphire
Oriental
Topaz - yellow
to yellow-brown sapphire
Smoky Topaz -
unscrupulous name for cut smoky quartz
Star Topaz -
yellow star sapphire
SIMILAR
GEMSTONES
Since topaz occurs in a great
range of colors, it may resemble many other gemstones:
Orange-brown and imperial topaz -
citrine, zircon, chrysoberyl, golden
beryl, orange-brown sapphire
Pink topaz - morganite, tourmaline, kunzite, rose quartz, spinel
Yellow topaz - chrysoberyl, heliodor, zircon, yellow sapphire
Blue topaz - aquamarine, zircon, spinel, euclase
Silver topaz - diamond, zircon, rock crystal, goshenite, danburite
Green topaz - green
beryl, tourmaline, peridot, hiddenite, green garnet
ALSO SEE
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