TOPAZ
topaz, imperial, blue, precious
 
Mineral information Topaz
Chemical composition Al2SiO4(F,OH)2
 
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The Mineral and Gemstone Kingdom
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Color Orange, yellow, brown, light blue to deep sky-blue, pink, colorless, white, light purple, greenish-blue, green
Hardness 8
SG 3.4 - 3.6
RI 1.610 - 1.638
DR .014
Luster Vitreous
   
 

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
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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

 

PICTURES

Special thanks to Gem Hut for most of our gem images. The gems displayed or others like them can be purchased through GemHut by clicking the link below each picture.

Blue Topaz
Picture: Blue Topaz
Size: 10.12 ct.

Cut: Pear
Gem: Gem Hut

Blue Topaz
Picture: Blue Topaz
Size: ???

Cut: Oval
Gem: Gem Hut

Imperial Topaz
Picture: Imperial Topaz
Size: 3.93 ct.

Cut: Pear
Gem: Gem Hut

Silver Topaz
Picture: Silver Topaz
Size: 10.15 ct.

Cut: Marquise
Gem: Gem Hut

Sky-blue Topaz
Picture: Sky-blue Topaz
Size: 2.54 ct.
(both gems)
Cut: Marquise

Gem: Gem Hut


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