Posted by

Pure topaz is colorless and transparent but is usually tinted by impurities; typical topaz is wine red, yellow, pale gray, reddish-orange, or blue brown. It can also be white, pale green, blue, gold, pink (rare), reddish-yellow or opaque to transparent/translucent.

Orange topaz, also known as precious topaz, is the traditional November birthstone, the symbol of friendship, and the state gemstone of the US state of Utah.

Imperial topaz is yellow, pink (rare, if natural) or pink-orange. Brazilian Imperial Topaz can often have a bright yellow to deep golden brown hue, sometimes even violet. Many brown or pale topazes are treated to make them bright yellow, gold, pink or violet colored. Some imperial topaz stones can fade on exposure to sunlight for an extended period of time.

Blue topaz is the state gemstone of the US state of Texas Naturally occurring blue topaz is quite rare. Typically, colorless, gray or pale yellow and blue material is heat treated and irradiated  to produce a more desired darker blue.Mystic topaz is colorless topaz which has been artificially coated giving it the desired rainbow effect.

ALL ABOUT

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 pleochroic 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.

 

 

 

 

 

Uses

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.

Other Names

Precious Topaz

Varieties

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.

Azotic Topaz  -   Orange-pink Topaz with a rainbow-like color effect. Its color is synthetically colored by film deposition of an extremely thin metallic layer over the top of the gemstone. Azotic Topaz is named by the company that introduced this, Azotic.

Imperial Topaz  -  Lustrous golden orange-yellow, orange-brown, or orange-pink variety   of Topaz and is its most valuable gem form. 

London Blue Topaz  -   Topaz with a deep sky-blue color. It is darker in tone than Swiss Blue Topaz.

Mystic Topaz  -  Multicolored Topaz with a rainbow-like color effect. Its color is synthetically colored by film deposition of an extremely thin metallic layer over the top of the gemstone.

Rutilated Topaz  -   Topaz with yellow needle-like inclusions of the mineral Limonite. Rutile Topaz is very similar in appearance to Rutilated Quartz, hence the name Rutile Topaz. However, the name is a misnomer, since unlike Rutilated Quartz which has inclusions of the mineral Rutile, the inclusions of Rutile Topaz are not Rutile but rather Limonite.

Sherry Topaz  -  Topaz with a light orange-brown to brownish-pink color.

Silver Topaz  -   Colorless form of Topaz. Synonym of White Topaz. 

Swiss Blue Topaz  -  Topaz with a sky-blue color. It is lighter in tone than London Blue Topaz.White Topaz  -   Colorless form of Topaz.

Treatments And Enhancements

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.

Topaz Sources

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).

Comments

comments powered by Disqus