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Topaz makes an ideal gem. A good hardness and desirable colors, combined with a relative abundance and availability makes it one the most popular gemstones. The most valuable colors of Topaz are the golden orange-yellow type, called Imperial Topaz, and the dark pinkish-red and orange-red colors. Value increases with a deepness of color in orange and reddish hues. The most commonly used colors of Topaz in jewelry are the blue types. It was not until this past century that blue Topaz became widespread on the gem market, since virtually all blue gem Topaz is irradiated and heat treated. |
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Chemical Formula |
Al2SiO4(F,OH)2 |
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Color |
White, Colorless, Blue, Red, Green, Yellow, Orange, Brown, Pink, Purple, Gray, Multicolored |
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Hardness |
8 |
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Crystal System |
Orthorhombic |
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Refractive Index |
1.610 - 1.638 |
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SG |
3.4 - 3.6 |
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Transparency |
Transparent |
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Double Refraction |
.014 |
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Luster |
Vitreous |
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Cleavage |
1,3 - basal |
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Mineral Class |
Topaz |
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Topaz is a fairly common and inexpensive gemstone. It can be found in huge and flawless crystals, which can be faceted into giant gemstones which can weigh thousands of carats. Some of the largest gemstone pieces ever cut were of Topaz.
Topaz is a hard and durable gemstone, and will not dissolve in most chemical solvents. However, it does have perfect cleavage which can make it prone to chipping or forming flaws if banged hard. Topaz is also a pleochroic gemstone and can have varied color intensity when viewed at different angles. Due to its good cleavage and pleocroic nature, care must be exercised when faceting Topaz gemstones.
Blue Topaz does occur in nature, but is rare and almost always lightly color. Most if not all blue Topaz used in jewelry has been irradiated and heat treated to artificially create the blue color. The original stones are colorless or lightly colored, and the radiation process gives them their deep sky-blue colors. In a few rare circumstances, some forms of blue Topaz tend to slightly fade in exposure to sunlight after extended periods of time.
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Topaz of all different colors are used in jewelry, in rings, earrings, necklaces, pendants, and bracelets. The blue, orange, and pink colors are most often cut as gemstones, and colorless Topaz is becoming increasingly popular as an inexpensive Diamond simulant. Gigantic gems and faceted spheres are cut from huge flawless crystals, and these make exquisite and exclusive collectors items. Topaz is rarely cut into cabochons.
Topaz is the traditional birthstone for November.
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With the exception of Imperial Topaz, all the variety names below are trade names that were coined by dealers in the jewelry trade. These names have become widely used despite them being names made up by jewelers in modern times. There are also several additional made-up variety names sometimes given to different forms and colors of Topaz. The list below only describes those names that have become terms used extensively in the jewelry market.
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Orange Citrine can resemble Topaz of the same color. Unfortunately, unscrupulous dealers have adapted many false name for Citrine to make it seem like the more valuable Topaz. With the exception of Imperial Topaz, any orange Topaz labeled with a prefix is almost always the less expensive heat treated Citrine. The list below describes terms that can be encountered, yet there are many additional prefixes that can be used by individual jewelers.
Bahia Topaz - False name for Citrine.
Brazilian Topaz - May refer to Topaz from Brazil, but is often a false name for Citrine.
Citrine Topaz - False name for Citrine.
Gold Topaz - False name for Citrine.
False Topaz - False name for Citrine.
Indian Topaz - Yellow to orange Sapphire.
King Topaz - Yellow to orange Sapphire.
Madeira Topaz - False name for Citrine.
Oriental Topaz - Yellow to orange Sapphire.
Smoky Topaz - Dark brown Smoky Quartz.
Spanish Topaz - False name for Citrine.
Star Topaz - Yellow Star Sapphire.
Topaz Quartz - False name for Citrine.
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Blue Topaz, the most commonly used Topaz color, is formed from colorless or lightly colored Topaz that is irradiated to make it blue, and then heat treated to stabilize the new color. Different forms of radiation treatment can produce different shades of blue. Most pink Topaz in
the gem trade is heat treated from yellow or brownish Topaz.
The colorful Mystic Topaz and Azotic Topaz are synthetically treated to produce their rainbow/multicolored effect using film deposition. The process involves bonding an extremely thin metallic film layer over the top of the gemstone, so that the interesting color effects are reflected from the crown.
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The largest Topaz producer is Brazil. Other sources are in Pakistan, Afghanistan, India, China, Burma (Myanmar), Sri Lanka, Japan, Russia, Ukraine, Australia, Madagascar, Namibia, Nigeria, Zimbabwe, Mexico, and the U.S. (California, Utah, and New Hampshire).
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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, Sapphire.
Pink Topaz - Morganite, Tourmaline, Kunzite, Rose Quartz, Spinel
Yellow Topaz - Chrysoberyl, Heliodor, Zircon, Yellow Sapphire
Blue Topaz - Aquamarine, Zircon, Spinel, Euclase
White Topaz - Diamond, Zircon, Rock Crystal, Goshenite
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Have a question about Topaz? Visit our Q&A Community and ask the experts!
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