On the nature of topaz
In times past, the term topaz was used to refer to any stone of a yellow or yellow-brown hue. These days topaz is found in a plethora of shades: brown, blue, green, yellow, orange, red, pink, and purple. The most common shade is yellow with a red tint, while the most valuable is pink to reddish-orange.
A topaz's color is caused by impurity elements or imperfections in its crystal structure. The element chromium causes pink, red, and purple shades in topaz. And defects in the crystal structure have a tendency to create yellow, brown, and blue colors. That said, it is important to keep in mind that topaz is regularly treated to turn the stone a particular color or to intensify its existing color. Colorless topaz is abundant and is often treated to turn it a pretty blue shade. Interestingly, topaz is also pleochroic, which means that the gemstone can show different colors from different directions.
In contrast to many other of our favorite gemstones, topaz can be found in enormous sizes. For example, a specimen found in Brazil weighed in at 596 pounds!
On finding topaz and what to look for
In the 18th century, the most important topaz mine was found in the Schneckenstein cliff in Saxony, which yielded remarkable crystals of wine-yellow. But today the most significant supplier is Brazil. Other deposits are found in numerous countries: Afghanistan, China, Myanmar, Russia, Namibia, Sri Lanka, and many others. In the United States, topaz can be found in Utah.
The rare naturally occurring light blue topaz can be found in northern Ireland, Scotland, and Cornwall, England.
Topaz are evaluated according their color, clarity, cut, and carat weight.
Color. Of all the shades of topaz, being so extremely rare, red is the most sought-after. Imperial topaz is the color of an orange-red flame. Another color to take note of is pink topaz. Pink topaz can match the beauty of a pink diamond or sapphire with the additional benefits of being less expensive and the availability of a good quality stone in larger sizes. Then there is the sherry wine topaz, the name denotes the color range from yellowish-brown or to orange.
Clarity. Topaz gemstones are often without visible inclusions or flaws. This is especially common in blue, yellow, and colorless topaz.
Cut. Topaz crystals are most often elongated or columnar. Because of this they are often cut in oval or pear shapes. On the other hand, if the stone happens to be strongly colored, the lapidary might be inclined to use the emerald cut to maximize color and to retain the most weight.
Carat. Topaz is inexpensive in smaller sizes, but prices rise for specimens above 10 x 8 mm.
Historical notes and other interesting facts about topaz
Origins of the name. The word topaz most like originates with a small island in the Red Sea, now called Zabargad but in old Greek was known as Topazios.
Anger management. In Renaissance times, people thought that topaz could break magic spells and dissolve anger.
For imperials only! The pink-shaded topaz mined in the Ural Mountains during the 1800s was called imperial topaz and so was named to honor the Russian czar. Ownership of imperial topaz was forbidden to all but the royal family.
Poison alert. At one time it was thought that a topaz would instantly lose its color if poison was present.
Resources and further reading
The Gemological Institute of America's Gem Encyclopedia.
Gemstones of the World. By Walter Schuman. Our go to book at Grimballs.
Jewels: A Secret History. By Victoria Finlay. An non-fiction adventure through time and place exploring the history of gems.
Smithsonian Institution National Museum of Natural History's Gem Gallery.
Gemstones: Beauty, Lore, and Fascination. By Michael Babinski.