The Gemstone Tanzanite
Tanzanite is a magnificent gemstone of striking brilliance and breathtaking blue purple or purple blue color.
At first, the stone was called Blue Zoisite but it was thought in the jewelry trade that the name seemed like blue suicide and wouldn't sell well. Therefore, as a part of the marketing campaign opsjaqyj , the gemstone was renamed by Tiffany as Tanzanite after the country of its origin, Tanzania.
Tanzanite is the blue or purple variety of the mineral zoisite (calcium aluminium hydroxy sorosilicate) which has the chemical formula of Ca2Al3(SiO4)(Si2O7)O(OH).
Contrary to the other gemstones which are known to mankind since ancient times and steeped in history, Tanzanite is a genuinely modern gemstone found only recently in 1967.
It was the Masaai tribesmen of Tanzania who stumbled upon the gleaming blue crystals in the foothills of Tanzania's Mount Kilimanjaro in 1967. It is fabled that the brown crystals lying on the parched earth were caught in a fire lighted by lightning that struck the grass-covered hills. As Tanzanite is a brownish color in its raw state, the crystals lying on the surface were never noticed. After the grassfire had heated the stones, they turned a bright, scintillating violet-blue. The Masai herders grazing cattle in the area spotted the beautiful blue color, becoming the first tanzanite collectors. Originally mistaken for Sapphire it was later on correctly recognized as belonging to the family of mineral Ziosite.
In the raw state most Tanzanite is largely brown. Heating upto 500 -600 degrees centigrade brings about this color to change to blue. This is a permanent and stable change. Practically all tanzanite gemstones of blue violet color have been heat-treated to boost the color. With the heat treatment, the gemstones do not alter in quality, only in appearance.
Similar to other gemstones, while picking a tanzanite gemstone, the four Cs ought to be considered which are as under:
Color
Color is the key attribute to be considered. The universally acknowledged official grading system for colored gems is the Gemological Institute of America (GIA) system but other grading systems also exist.
The GIA grade for stones with the most desirable color is bv 6/5 or vB 6/5 and is kept for the deep blue stones with a hint of violet. The other industry grades given to such stones are A,A,A,A or A,A,A. These are excellent gemstones truly deserving your attention and your investment.
As the color fades opsjaqyj , the GIA grades given are bV 6/4 (other grading systems A or A,A) and GIA grades bV 4/4 (other systems B).
The most outstanding attribute of Tanzanite is that most of the good quality stones include a Trichroic effect. A Gemstone displaying Trichroic effect can reflect three distinct colors at a time depending on the angle from which you look at the stone. One direction is blue, another purple, and another bronze opsjaqyj , adding delicate depths to the color.
Clarity
Clarity is the 2nd most important factor of the 4 c's when determining Tanzanite quality. Clarity refers to how inclusion-free a gemstone is. Once again there is the GIA system along with other trade based systems in use. Tanzanite should be at least eyeclean but preferably loupeclean too. Top stones are loupeclean. The GIA grades for clarity are VVS very very slightly included opsjaqyj , VS very slightly included, SI1 - SI2 slightly included and the lowest grade I1, I2 and I3 given to imperfect stones.
A top quality stone must be of VVS grade. A lower clarity grade will affect the value downwards and indicates a lower grade stone.
CARAT WEIGHT
Generally tanzanite gemstones stones come in the 1 to 10 carat range size. As weight increases stones in the same quality gemstone will cost you more per carat.
Cut
Tanzanites are found in a variety of shapes and cutting styles. Ovals and cushions are the most prevalent, but rounds are also seen opsjaqyj , as are other shapes, including emerald cuts, trillions, etc. Cabochon-cut tanzanites are not often seen.
The tanzanite gemstone goes well with every kind of jewelry be it Yellow Gold, White Gold Or Diamonds. But since it is a comparatively soft gemstone with a hardness of 6.5 on the mohs scale of mineral hardness it is usually worn as an earring or pendant. It is bezel set in a ring to give it protection.
Don't expose the gemstone to sudden changes of temperature like going from hot tubs to very cold water and reaching from ovens to a cold sink.
You should protect your tanzanite jewelry from accidental impacts with hard surfaces and avoid wearing it while carrying strenuous physical tasks like gardening, washing clothes or cooking.
Usually the brilliance of a tanzanite gemstone gets masked by dirt and finger prints. You can clean it by soaking it in very mild soapy water and rinse it with lot of water. You can polish it with very soft clean cloth.
You should protect your tanzanite gemstone from other pieces of jewelry by storing it in a soft cloth.
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