Topaz, the Invisible Gem
For centuries, Topaz has been associated with the color yellow, so the common belief was that all yellow Gems were Topazes and that Topazes were only yellow. Today we know that Topaz appears in various colors: from colorless to red, pink, purple, yellow, orange and brown, with various shades and saturations.
Some Topazes grow in metamorphic rocks, others in hydrothermal veins, but most are found in the cavities of igneous rocks such as granites or pegmatites.
In ancient times, especially during the Middle Ages, Topaz was believed to be the Gem suited to cure psychic disorders and to prevent death. The ancient Greeks, even more imaginatively, thought that wearing a Topaz would make one invisible.
Imperial Topaz, precious Topazes and famous Topazes
Among the most precious Topazes are certainly the Imperial Topaz, the yellow Topaz, the brown Topaz, the pink Topaz and the sherry Topaz (the trade term used to indicate the yellow-brown variety).
The name Imperial Topaz is in honor of the 17th-century Tsars, who were in love with this Precious Stone.
It is said that the Tsars wore Topaz only on the condition that it had emerged from Russian soil. Even today some deposits are present in Russia, in the Ural Mountains.
Imperial Topaz usually has few inclusions and therefore belongs to the category of eye-clean Gems.
The famous Blaze Imperial Topaz is one of the most famous topazes in history, weighing a remarkable 97.45 carats and exhibited at the Field Museum of Natural History in Chicago. Among the most famous Topazes in the world, the Braganza Diamond stands out, which became famous not so much for its beautiful color (it is in fact a colorless white topaz), but rather because for centuries it was thought to be a 1680-carat Diamond!
Blue Topaz, which is extremely rare in nature, is very abundant on the market and is always the result of one or more treatments. The colors created by Topaz treatments can have various shades of blue, such as the dark blue, called by the trade term London blue (but also Swiss blue, super blue or maxi blue). The trade term sky blue, on the other hand, indicates a blue with a light tone.
Where to find and dig these so-coveted Gems?
The Ouro Preto area, in Minas Gerais, is the world’s largest source of Imperial Topaz and Red Topaz. One of the most important mines in this area is the Capao Mine, where only 1 rough of Imperial Topaz out of every 100 extracted is facetable. Most rough Imperial Topaz measures less than 2.5 x 10 cm, but an impressive 200-kg rough has also come to light.
In Ghundao Hill, Pakistan, Pink and Red Topazes are mined.
The high-quality Pakistani pink Topaz deserves a more in-depth discussion: at the top of quality it does not even need treatments. Pakistani pink Topaz reaches maximum value when it exhibits pink with a slight purple tint: this color is called by the trade term Cyclamen Topaz.
One of the largest Topaz mines in the world is in Utah, in the Topaz Mountains. Numerous tours are organized to this mine to satisfy the curiosity of tourists.
Imperial Topaz with basal cleavage
Among the main characteristics of Topaz there is the cleavage in one direction, parallel to the base of the crystal. This type of cleavage is gemologically defined as basal cleavage. The basal cleavage forces the cutter to take maximum caution during the cutting phase, and also imposes caution on whoever wears it.
A strong blow could in fact break it; for this reason it is recommended to protect it well when mounting it in a ring. The ultrasonic cleaning machine should also be avoided when it is time to clean it.
The preferable setting is certainly the bezel setting, which consists of a thin strip of metal built to wrap the Gem and hold it still. Topaz is, however, a very versatile stone and adapts well to rings, necklaces and bracelets.
