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Topaz

BIRTHSTONE:

Precious topaz is a birthstone for November and blue topaz is also a birthstone for December. Blue topaz is the gem of the 4th anniversary and Imperial topaz is the gem of the 23rd anniversary.

TOPAZ DESCRIPTION: 

Topaz
This selection of gems from Ouro Prêto, Brazil, and Russia's Ural Mountains, displays the golden orange to pinkish red color range of precious topaz. The gems range from 7.61 to 14.33 carats in size.
Many consumers know topaz as simply an inexpensive blue gem. They’re surprised to learn that its blue color is hardly ever natural: It’s almost always caused by treatment. They might also be surprised to know that topaz has so many more colors to offer gem lovers, including pinks and purples that rival the finest fancy sapphires.

Reddish Purple Pear-shaped Topaz
This superb reddish purple pear-shaped topaz from Brazil's Capão mine displays the gem’s top color. - Courtesy Dr. Wagner Colombarolli
Topaz is allochromatic, which means that its color is caused by impurity elements or defects in its crystal structure rather than by an element of its basic chemical composition. The element chromium causes natural pink, red, and violet-to-purple colors in topaz. Imperfections at the atomic level in topaz crystal structure can cause yellow, brown, and blue color. Brown is a common topaz color, and the gem is sometimes mistakenly called “smoky quartz.”

Imperial Topaz
So far, commercial deposits of imperial topaz are found in a single area of the world: Ouro Prêto in Brazil. The 6.00-carat pear shape and 3.82-carat antique cut display nuances of the gem's color. - Courtesy Suwa & Son
Topaz Crystal
Against the light, this crystal's color zones and high clarity stand out clearly. It might be possible to fashion a unique gem from this piece. - Courtesy Dr. Wagner Colombarolli
Topaz actually has an exceptionally wide color range that, besides brown, includes various tones and saturations of blue, green, yellow, orange, red, pink, and purple. Colorless topaz is plentiful, and is often treated to give it a blue color.

Topaz Crystals
Topaz crystals are typically elongated, with grooves parallel to their lengths. For this reason, they're commonly cut into long oval or pear shapes. These crystals show orange, pink, and brown colors. - Eric Welch/GIA
The color varieties are often identified simply by hue name—blue topaz, pink topaz, and so forth—but there are also a couple of special trade names. Imperial topaz is a medium reddish orange to orange-red. This is one of the gem’s most expensive colors. Sherry topaz—named after the sherry wine—is a yellowish brown or brownish yellow to orange. Stones in this color range are often called precious topaz to help distinguish them from the similarly colored but less expensive citrine and smoky quartz.

Topaz is also pleochroic, meaning that the gem can show different colors in different crystal directions.
 
TOPAZ QUALITY FACTORS:
Uniquely Cut Topaz
Blue topaz makes a perfect gem material for artistic carvings. - Lydia Dyer, courtesy of John Dyer & Co.
Color
Red is one of the most sought-after topaz colors and represents less than one-half of 1 percent of facet-grade material found. The color the trade calls imperial topaz is highly prized and very rare. Many dealers insist that a stone must show a reddish pleochroic color to be called imperial topaz. The reddish pleochroic color often appears at the ends of fashioned gems—like pears and ovals—that have an otherwise yellow-to-orange bodycolor.

Highly Prized Imperial Topaz
Imperial is one of the most highly prized topaz colors, as seen in this spectacular prize-winning, orangy-red, flame-shaped gem. - Gem courtesy of John Dyer & Co.
A fashioned topaz that displays a combination of two colors is called bicolor topaz. Some say that pink topaz, often called rose topaz, resembles a pink diamond or a bright pink sapphire. Pink topaz has certain advantages over these two gems. It’s much less expensive than pink diamond, and it’s often available in larger sizes than either diamond or sapphire.

Dealers often use the trade term “sherry topaz” for yellowish brown or brownish yellow to orange topaz. The term comes from the color of sherry wine. Stones in that color range are also sometimes called precious topaz. This helps distinguish them from less expensive citrine and smoky quartz, both of which look similar to, and are frequently misrepresented as, topaz.

Golden or yellow topaz lacks the prized red overtones of imperial topaz. It’s also much more abundant and therefore less valuable. Although brown topaz is also less valuable, it has been used in striking pieces of jewelry and ornamental art.

In nature, topaz is most commonly colorless, and naturally strong blue gems are extremely rare. In the marketplace, however, strong blue shades are plentiful. Treatments are the reason for this. Treaters use a combination of radiation and heat to produce blue hues in topaz. Since the 1970s, treatments have brought blue topaz to a broad market.

Blue Topaz
Irradiation and heat treatment transform colorless topaz to various shades of blue. Starting in the 1970s, treatment created a huge market for inexpensive blue topaz. - © GIA & Tino Hammid
When it was first introduced to the market, treated blue topaz sold for $20 to $40 per carat. But oversupply led to huge drops in wholesale prices, down to a few dollars or less per carat. Today, blue topaz is basically a mass-market gem, and price is often the most important consideration for many buyers. Uniformity of color and cut is also important, especially for mass-market jewelry manufacturers.

Treated Blue Topaz
The nature of the starting material and the type of treatment determine the blue that results. These treated topaz stones, weighing from 2.72 carats to 7.86 carats, show a range of hue, tone, and saturation. - Courtesy Chuck Ashbaugh
Clarity
Fashioned topaz gems are often free of visible inclusions or flaws. This especially true of blue, colorless, and yellow topaz.

12.25-carat Untreated Topaz
This ring, designed by Maria Canale, holds a 12.25-carat untreated topaz from Brazil. The gem has no visible inclusions. - Courtesy Richard Krementz Gemstones
Cut
Because topaz crystals are usually elongated or columnar, they’re often cut as long oval or pear shapes to improve yield. If the rough is strongly colored, the cutter often chooses the emerald cut because that cutting style maximizes color and retains the most weight.

Topaz is cut in a wide variety of shapes and cutting styles. Production includes all the standard gem shapes such as ovals, pears, rounds, cushions, triangles, marquise, and emerald cuts as well as designer-inspired fantasy shapes.

14.68-carat Topaz
A modern mixed cutting style dramatically intensifies the color of this 14.68-carat bright blue topaz. - Lydia Dyer, Topaz StarBrite courtesy of John Dyer & Co.
Cutting styles are also well represented. Brilliant cuts with triangular and kite-shaped facets, step cuts with concentric rows of parallel facets, and mixed cuts usually consisting of brilliant-cut crowns and step-cut pavilions are all common. Designer cuts fashioned by hand and machine are popular, too.

Treated Blue Topaz
The uniform color of treated blue topaz makes it a highly suitable material for cutting into standard sizes for jewelry.
Because there is an abundant supply of treated blue topaz, it’s often cut into calibrated sizes for use in mass market and multi-stone jewelry.

Carat Weight
Standard topaz cuts for the jewelry industry include a wide range of shapes and sizes. The gem is inexpensive in smaller sizes, but prices rise for gems above 10×8 mm.

61.78-carat Carved Topaz
This 61.78-carat carved topaz is a truly unique sculptural piece. Skilled workmanship intensifies the blue color to produce an effect like shimmering droplets of water. Blue topaz makes a perfect material for large carvings due to availability in large sizes. - Lydia Dyer, Blue Topaz Sculptural Gem courtesy of John Dyer & Co.
 
ALL CONTENT IS FROM:"Topaz." GIA. N.p., n.d. Web.
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