History and General Information of Natural Topaz Gemstone

The word topaz has been associated with the color yellow and more specifically any gemstone with a yellow or golden hue for centuries. The name topaz is believed to have been derived from the sanskrit word ?tapas?, meaning fire. It was the mystic fire topaz that was considered to have many healing properties.

However, the modern name of topaz was coined by Henckel, who described the specific mineral deposits in Saxony, Germany with this name.

Topaz from Ceylon (now Sri Lanka) was used in the 1700s in Egypt and Rome. However, the gemstone gained popularity in Europe only in the 1800th century. Its popularity increased to such an extent in Europe that topaz jewelry became extremely popular and coveted. The gemsotne was also used extensively with the finest diamonds in the jewelry of the Victorian era.

This beautiful gemstone owes its popularity in the middle ages to the myths attached to it. The mystic topaz was believed to strengthen the mind and prevent sudden death of the wearer. Genuine natural topaz was also said to cure weak eyesight. The gemstone had to be soaked in wine for three day and three nights and then placed on the eye for the affect to take place.

Handcrafted mystic topaz rings, topaz necklaces, mystic topaz bracelets and topaz beads were worn to benefit from the positive aspects that the stone transferred on to the wearer.

Composition Of Topaz Gemstone

The chemical composition of natural topaz is  fluosilicate of aluminum (Al 2 (F, OH)2  SiO4). The specific gravity of the natural topaz crystals ranges from 3.53 to 3.56 and its refractive index falls between 1.61 and 1.638. The gem?s hardness on Mohs scale is 8. But the topaz crystal has one undesirable physical property - an unstable and week atomic structure.

Varieties

Topaz crystals are found in various colors and these are known by different names in trade circles. Although these names are used in the market, there is no standard nomenclature that is followed. Due to the various names used in the market for topaz, one can never be sure of the classification of the variety of the gem according to its color. Gemologically speaking, different colored gemstones are named according to their color. A pink gem is called a pink topaz and a blue gem is called a blue topaz, yellow gem is called as yellow topaz and so on.

Physical Properties

Topaz Color

The lovely topaz gemstone can be found in a wide variety of colors like red, pink, purple, yellow, yellow-gold, orange, orange-pink, brown, sky-blue, blue green and even colorless. In a certain light, the sky-blue topaz looks almost silver.

The reddish-orange to orange-red to rich red topaz is called the ?Imperial Topaz? in trade circles. The genuine imperial topaz gemstone can fetch a high price in the market and  is a popular gem among the topaz group due to its lovely color. Imperial topaz crystals are often carefully cut and used in jewelry.

The yellowish-brown to brownish-yellow to orange topaz is called sherry topaz and some topaz gemstones in the same color range are also sometimes called precious topaz. The yellow topaz, as we know, is the most common of all topaz colors and is sometimes also referred to as the golden topaz.

The pink topaz is sometime called the rose topaz. The trace element for the pink, red or purple topaz is mineral chromium. Color center (mean minor atomic substitutions and defects in the crystal structure followed by radiation damage) is the cause of color in yellow, brown and blue topaz. The presence of both chromium and color center results in an orange colored topaz.

Cut

Due to the elongated form of the rough crystals of this gem, usually long faceted oval or pear shape cuts are used to make the most of its color. To retain the color and weight, the topaz gem should be cut in an emerald cut. Due to it weak atomic structure it is very important for the rough topaz to be cut with precision, in a well-planed manner.

However, other than the oval shape or the pear shaped faceted topaz, the gemstone can also be cut into other cuts like the cabochon cut, the square cut, octagon shape or the round cut.

Carat

In the 1940s, three large topaz gemstones were mined from the Brazilian mines of Minas Gerais. These topaz crystals mined weighed about 596 (596 pounds or 271 Kg of rough topaz - the worlds largest Topaz), 300 and 255 pounds respectively and are now housed in the American Museum of evolution.

Clarity

Topaz is a transparent and bright gemstone. The most striking inclusions found in a topaz gemstone are drop-shaped cavities containing two or even three immiscible liquids (with a clear dividing line). These topaz teardrop mineral inclusions can be seen on close inspection of the gemstone. However, the presence of even a faint inclusion only reduces the value of the gemstone and good quality, clean gems that do not have any inclusions, especially to the visible eye get higher prices.

Price and Buying of Topaz Gemstone

The most valuable and rare topaz varieties are the red and the pink topaz. However, most colors of faceted topaz gemstones are commonly used in jewelry, making topaz one of the popular gemstones. A genuine topaz jewelry item can cost a fortune if it includes all the rare colors of the topaz.

Markets and Producers of Topaz

Topaz is found in India, Brazil, Mexico, United States, Burma (now Myanmar), Madagascar, Russia, Namibia, Zimbabwe and Nigeria.

Treatments done on Topaz Gemstone 

Most of the blue topaz gemstones found in the market are treated especially since they are rare and it is difficult to find an untreated or unheated blue topaz. Among these the natural blue topaz is extremely rare. When a combination of heat and radiation treatments is carried out on a colorless or greenish gem it turns into blue topaz. Irradiation is also on the treatments that are carried out on the gem.

Simulants of Topaz Gemstone

Topaz gemstone is usually a simulant for the more famous yellow sapphire gemstone. This is the case which happens usually in India as Yellow Sapphire is often worn for astrological purpose in India. Though gems like tourmaline, aquamarine, Spinel, quartz, ruby, sapphires, danburite, apatite and sphene are some of the stones which resemble topaz.

Interesting Trivia and other Topaz facts

Topaz is the official state gem of Texas and Utah in the United States.

Topaz is the birthstone for people born in the month of November (yellow topaz) and December (blue topaz). Hence Topaz is also called as November birthstone. It is a talisman for the zodiac sign of Sagittarius.

Reference

1) Webster.
2) Gemmology by Peter G.Read.
3) Handbook of Gem Identification -   Richard  T.Liddicoat, jr.
4) Gems & Crystals - From the American  Museum of Natural History - Anna S.Sofianides  and George E.Harlow.