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Dahl Jewelers, Woodbridge, VA
Tanzanite, Tanzanites

Tanzanite has the distinction of being the newest member of the gemstone family. This beautiful material was not even discovered until 1967 when prospectors in Tanzania found deposits of a new type of zoisite.

This new gem had extraordinary properties. It was transparent and had a high clarity. It was a deep blue when looked at from one angle. From another perspective, it would appear to be purple. Also, it could appear to be one color indoors and another when viewed in the sunlight.

Tiffany's in New York acquired some of this new stone and, upon learning that it had yet to be named, christened it tanzanite after its country of origin.

Tanzanite quickly became a favorite with many people. Good supplies of tanzanite had been found and good quality tanzanite could be acquired quite reasonably. Researchers also discovered that most off-colored stones could be improved by heating. Then these tanzanites would also be the deep rich blue-purple with flashes of other color that the public was now wild about.

Today, although there is no lore or legends about tanzanites, there is indeed a growing demand and love for this beautiful gem.

As new finds of tanzanite became scarcer and the demand higher, the price of tanzanite steadily rose. Tanzanites, which went for hundreds of dollars a few short years ago, now bring thousands. Demand for tanzanite now far outstrips the supply and, judging from past records, tanzanite will continue to be a favorite among people everywhere.

Description of Tanzanite Qualities That We Sell

High quality: Deep purplish/blue cast. Very lively and clean. Cutting is good but many of the darker stones can be deep cut in order to get that look.
Medium quality: Medium purplish/blue cast. Lively and clean. The deeper the color, the more inclusions.
Low quality: Light purple shade, mostly shallow, poor cut stones. Clean to slightly included. The darker the stone, the more included.

Please check here for a note about colored gemstone qualities.

Tanzanite Properties

Hardness: 6.5 to 7
Toughness: Poor
Specific gravity: 3.35
Refractive index: 1.691 to 1.70
Double refraction: +0.009
Main sources: Tanzania
Treatment: Heat treated to change color from pale brown to a vibrant blue/purple (color is stable).
Reaction to heat: Very poor, stone will fracture or break.

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Open Monday through Friday, 9:30am to 5:30pm; Saturday, 9:30am to 3:00pm.
3138 Golansky Boulevard, Suite 102, Woodbridge, VA 22192. Phone 703-878-0888.