What color is it?: Tanzanite will be a combination of equal colors of blue and purple. Some lesser quality stones will only offer a dominate blue color. These are less valuable than the stones that offer a true tanzanite color combination of blue/purple. The intensity of these colors can vary due to light source under which it is viewed. There is also a reddish color that is the third color of tanzanite that your eye cannot see. We will discuss this in a later section.
What is the story behind this gemstone?: Tanzanite is a very rare stone not only for its color, but also because there is only one place in the world where tanzanite is commercially mined. That is, of course, Tanzania. So not only is it rare gemologically, its also rare geographically. And when the region that is producing these rare stones is mined out, there may not be any more tanzanite available. It should also be noted that the stone has only been on the market for about 30 years. So there will not be a lot of estate jewelry with tanzanite in case someone is making that claim.
Can I wear it everyday?: Basically yes with some exceptions. With a hardness of about 7 it can be a bit brittle. So for normal everyday wear it is fine. But once again, any heavy banging around or framing houses should be done without wearing your tanzanite.
Is it expensive?: Prices have gone up over that past few years and will most likely continue to do so. A good quality tanzanite in the 3-5 carat range can cost upwards of US$1,000.00 per carat. So if you are thinking of buying a tanzanite...now would be a good time.
Is it a birthstone?: No.
What do I need to know before going shopping?: Stay with a well trained, independent professional jeweler. There are not any synthetic tanzanites on the market. But there are many imitations that have been developed in an effort to fool people. So stay with a professional, independent jeweler who will be able to properly identify these stones for your purchase.
Rough tanzanite before and after heat treatment
Source: Tanzania only commercially viable source
Formation: Forms most often in granitic intrusions
Crystal System: Orthorhombic
Unusual Properties: Strong Trichroism with two of the colors, blue and purple, being readily visible to the unaided eye. A Chelsea Filter will view the third reddish brown color.
Treatment: Tanzanite is a brownish color (much
like the third trichroic color) when it comes out of the ground.
As shown in the two photos above the material turns to its blue/purple
color after heating.
For the gemological information on this gemstone we invite you to join us in the
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