Although rough tanzanite was discovered by accident and misidentified as several stones and minerals, once the beauty and rarity of the stone was realized, it soon became valuable and wanted by both gemstone collectors and the most well known jewelers.

Tanzanite Color and Properties

In its rough state, tanzanite is a purple-blue color, and often with yellow and brown spots that must be heat treated to remove. The gemstone has unique light dispersion and refractive features. Tanzanite reflects different colors with light when viewed at different angles. It is also considered to be birefringence, meaning that two different paths are taken when light is shined through the stone. These features allow the gemstone to appear bluer when looked through from the top and purple when looked through from the top.

Tanzanite gemstones are considered to have a hardness of between 6 and 7, which makes it fragile, but still usable for jewelry wear. The most wanted color is the unique bluish-purple tanzanite that is created after treatment.

History of Tanzanite

Discovered only in 1967, tanzanite is a new addition to the world of gemstones. A man named de Souza, who lived in Tanzania, discovered the stone while in search of gold. At first, he thought the gemstone was a purple sapphire, but later learned that it was more than that.

Once he realized that it was in fact not a sapphire, he mistook it again for a different gemstone. After testing and consideration by geologist and universities, it was determined that a new gemstone had been discovered.

It was immediately realized how beautiful the gemstones were, and that a market needed to be created. At first the Saks Department stores were asked to carry the stone, but the store chose not to invest. It was then that two rings that had been created from the first discovered tanzanite gemstones were shown to the head of the Tiffany & Co jewelry store. With no hesitation, Tiffany’s jumped at the opportunity and named the gem tanzanite.

The market for tanzanite has grown over the last few decades and the gemstone has become very popular. In 2002, it was realized that some sort of protocol was needed to ensure that the stones were not used to finance terrorist groups. Also in 2002, the American Gem Trade Associated included tanzanite as an addition to the list of birthstones for December.

Due to the high demand of tanzanite, very convincing synthetic gemstones have been created. In Russia, the synthetic material Tanzanion is manufactured, and although very comparable to real tanzanite, it is not as brilliant or as valuable.

Rough Tanzanite Treatment

Some rough tanzanite can be purchased, but most of the gemstones are first treated with heat before being sold. Like most other gemstones, heat enhances the colors of the tanzanite gemstones, and also creates new colors as well. The stone when first mined is not attractive and tends to be browner in color than any other colors. The heating is done at very extreme temperatures and by one plane of the stone at a time, but only when the stone has not been exposed to heat in it natural environment. If the gemstones are already been naturally heat treated, then they cannot be reheated due to their fragile state.

It is said that before the discovery of rough tanzanite in 1967, locals of the Merelani Hills in Tanzania noticed that after a great wildfire, rocks that at one time were brown and dull turned blue after the fire scarred them. This was probably the first sighting of Tanzante.

This is the reason why care for treated tanzanite must be done carefully and with certain guidelines. Many fine gemstones can be steam cleaned to keep the brilliance the same, but this cleaning method can change the color of the stone and cause it to break, leaving you with nothing but a rock as valuable as a paperweight.

Once the gemstones are heat treated, they turn an indigo or violet color that can change in different lighting, then, they are cut to size. Most rough tanzanite gemstones are of decent size, but some of the largest known stones ever discovered have been tanzanite. The largest being 22 cm wide, and weighing 16,839 carats.

The Business of Tanzanite

Since the vice president of Tiffany & Co first decided to market and sell tanzanite gemstones as a fine stone, the market for them has grown tremendously. The business aspect of tanzanite is very similar to that of diamonds. Not only are they valued by the same criteria, but are also controlled in the same ways. The criteria are cut, clarity, and color, with most emphasis on the color. The rough tanzanite stones that are treated are classified by either being mostly violet or mostly blue, from there the clarity and cut of the gem is taken into consideration before it is labeled with a fiscal value. To ensure that tanzanite gemstones that are on the market are real, their distribution is highly controlled. Very similar to the diamond market, one company distributes the stone to authorized dealers. This ensures that when you buy a tanzanite gemstone from one of the authorized dealers, you are receiving a quality gem that is truly tanzanite and not a convincing synthetic.

Tanzanite has become very popular over the recent years, and prices have increased. But it is believed that the supply of the rare gemstone will be depleted someday soon, making the prices soar higher than ever. Even though the first tanzanite gemstone was just a lucky find, it has introduced a new fine gem to our society that is spectacular.

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